OBG Management

During the past 45 years, the cesarean delivery (CD) rate in the United States has increased from 5.5% in 1970 to 33% from 2009 to 2013, followed by a small decrease to 32% in 2014 and 2015.¹ Many clinical problems cause clinicians and patients to decide that CD is an optimal birth route, including: abnormal labor progress, abnormal or indeterminate fetal heart rate pattern, breech presentation, multiple gestation, macrosomia, placental and cord abnormalities, preeclampsia, prior uterine surgery, and prior CD.² Recent secular trends that contribute to the current rate of CD include an adversarial liability environment,^3,4 increasing rates of maternal obesity,⁵ and widespread use of continuous fetal-heart monitoring during labor.⁶

Wide variation in CD rate has been reported among countries, states, and hospitals. The variation is due, in part, to different perspectives about balancing the harms and benefits of vaginal delivery versus CD. In Europe, in 2010 the CD rates in Sweden and Italy were 17.1% and 38%, respectively.⁷ In 2010, among the states, Alaska had the lowest rate of CD at 22% and Kentucky had the highest rate at 40%.⁸ In 2015, the highest rate was 38%, in Mississippi (FIGURE).⁹ In 2014, among Massachusetts hospitals with more than 2,500 births, the CD rate ranged from a low of 22% to a high of 37%.¹⁰

Clinicians, patients, policy experts, and the media are perplexed and troubled by the “high” US CD rate and the major variation in rate among countries, states, and hospitals. Labor management practices likely influence the rate of CD and diverse approaches to labor management likely account for the wide variation in CD rates.

A nationwide effort to standardize and continuously improve labor management might result in a decrease in the CD rate. Building on this opportunity, the American College of Obstetricians and Gynecologists (ACOG) and the Society of Maternal-Fetal Medicine (SMFM) have jointly recommended new labor management guidelines that may reduce the primary CD rate.⁸

The ACOG/SMFM guidelines encourage obstetricians to extend the time for labor progress in both the 1st and 2nd stages prior to recommending a CD.⁸ These new guidelines emphasize that for a modern obstetrician, patience is a virtue. There are 2 important caveats to this statement: to safely extend the length of time of labor requires both (1) a reassuring fetal heart rate tracing and (2) stable maternal health. If the fetus demonstrates a persistent worrisome Category II or a Category IIIheart-rate tracing, decisive intervention is necessary and permitting an extended labor would not be optimal. Similarly, if the mother has rapidly worsening preeclampsia it may not be wise to extend an induction of labor (IOL) over many days.

There are risks with extending the length of labor. An extended duration of the 1st stage of labor is associated with an increased rate of maternal chorioamnionitis and shoulder dystocia at birth.¹¹ An extended duration of the 2nd stage of labor is associated with an increase in the rate of maternal chorioamnionitis, anal sphincter injury, uterine atony, and neonatal admission to an intensive care unit.¹² Clinicians who adopt practices that permit an extended length of labor must weigh the benefits of avoiding a CD against these maternal and fetal complications.

Active phase redefined

Central to the ACOG/SMFM guidelines is a new definition of the active phase of labor. The research of Dr. Emmanuel Friedman indicated that at approximately 4 cm of cervical dilation many women in labor transition from the latent phase, a time of slow change in cervical dilation, to the active phase, a time of more rapid change in cervical dilation.^13,14 However, more recent research indicates that the transition between the latent and active phase is difficult to precisely define, but more often occurs at about 6 cm of cervical dilation and not 4 cm of dilation.¹⁵ Adopting these new norms means that laboring women will spend much more time in the latent phase, a phase of labor in which patience is a virtue.

The ACOG/SMFM guidelines

Main takeaways from the ACOG/SMFM guidelines are summarized below. Interventions that address common obstetric issues and labor abnormalities are outlined below.

Do not perform CD for a prolonged latent phase of labor, defined as regular contractions of >20 hours duration in nulliparous women and >14 hours duration in multiparous women. Patience with a prolonged latent phase will be rewarded by the majority of women entering the active phase of labor. Alternatively, if appropriate, cervical ripening followed by oxytocin IOL and amniotomy will help the patient with a prolonged latent phase to enter the active phase of labor.¹⁶

For women with an unfavorable cervix as assessed by the Bishop score, cervical ripening should be performed prior to IOL. Use of cervical ripening prior to IOL increases the chance of achieving vaginal delivery within 24 hours and may result in a modest decrease in the rate of CD.^17,18

Related article:
Should oxytocin and a Foley catheter be used concurrently for cervical ripening in induction of labor?
 

Failed IOL in the latent phase should only be diagnosed following 12 to 18 hours of both ruptured membranes and adequate contractions stimulated with oxytocin. The key ingredients for the successful management of the latent phase of labor are patience, oxytocin, and amniotomy.¹⁶

CD for the indication of active phase arrest requires cervical dilation ≥6 cm with ruptured membranes and no change in cervical dilation for ≥4 hours of adequate uterine activity. In the past, most obstetricians defined active phase arrest, a potential indication for CD, as the absence of cervical change for 2 or more hours in the presence of adequate uterine contractions and cervical dilation of at least 4 cm. Given the new definition of active phase arrest, slow but progressive progress in the 1st stage of labor is not an indication for CD.^11,19

“A specific absolute maximum length of time spent in the 2nd stage beyond which all women should be offered an operative delivery has not been identified.”⁸ Diagnosis of arrest of labor in the 2nd stage may be considered after at least 2 hours of pushing in multiparous women and 3 hours of pushing in nulliparous women, especially if no fetal descent is occurring. The guidelines also state “longer durations may be appropriate on an individualized basis (eg, with use of epidural analgesia or with fetal malposition)” as long as fetal descent is observed.

Patience is a virtue, especially in the management of the 2nd stage of labor. Extending the 2nd stage up to 4 hours appears to be reasonably safe if the fetal status is reassuring and the mother is physiologically stable. In a study from San Francisco of 42,268 births with normal newborn outcomes, the 95th percentile for the length of the 2nd stage of labor for nulliparous women was 3.3 hours without an epidural and 5.6 hours with an epidural.²⁰

In a study of 53,285 births, longer duration of pushing was associated with a small increase in the rate of neonatal adverse outcomes. In nulliparous women the rate of adverse neonatal outcomes increased from 1.3% with less than 60 minutes of pushing to 2.4% with greater than 240 minutes of pushing. Remarkably, even after 4 hours of pushing, 78% of nulliparous women who continued to push had a vaginal delivery.²¹ In this study, among nulliparous women the rate of anal sphincter injury increased from 5% with less than 60 minutes of pushing to 16% with greater than 240 minutes of pushing, and the rate of postpartum hemorrhage increased from 1% with less than 60 minutes of pushing to 3.3% with greater than 240 minutes of pushing.

I am not enthusiastic about patiently watching a labor extend into the 5th hour of the 2nd stage, especially if the fetus is at +2 station or lower. In a nulliparous woman, after 4 hours of managing the 2nd stage of labor, my patience is exhausted and I am inclined to identify a clear plan for delivery, either by enhanced labor coaching, operative vaginal delivery, or CD.

Operative vaginal delivery in the 2nd stage of labor is an acceptable alternative to CD. The rate of operative vaginal delivery in the United States has declined over the past 2 decades (TABLE). In Sweden in 2010 the operative vaginal delivery rate was 7.6% with a CD rate of 17.1%.⁷ In the United States in 2010 the operative delivery rate was 3.6%, and the CD rate was 33%.¹ A renewed focus on operative vaginal delivery with ongoing training and team simulation for the procedure would increase our use of operative delivery and decrease the overall rate of CD.

Related article:
STOP using instruments to assist with delivery of the head at cesarean
 

Encourage the detection of persistent fetal occiput posterior position by physical examination and/or ultrasound and consider manual rotation of the fetal occiput from the posterior to anterior position in the 2nd stage. Persistent occiput posterior is the most common fetal malposition.²² This malposition is associated with an increased rate of CD.²³ There are few randomized trials of manual rotation of the fetal occiput from posterior to anterior position in the 2nd stage of labor, and the evidence is insufficient to determine the efficacy of manual rotation.²⁴ Small nonrandomized studies report that manual rotation of the occiput from posterior to anterior position may reduce the CD rate.^25–27

For persistent 2nd stage fetal occiput posterior position in a woman with an adequate pelvis, where manual rotation was not successful and the fetus is at +2 station or below, operative vaginal delivery is an option. “Vacuum or forceps?” and “If forceps, to rotate or not to rotate?” those are the clinical questions. Forceps delivery is more likely to be successfulthan vacuum delivery.²⁸ Direct forceps delivery of the occiput posterior fetus is associated with more anal sphincter injuries than forceps delivery after successful rotation, but few clinicians regularly perform rotational forceps.²⁹ In a study of 2,351 women in the 2nd stage of labor with the fetus at +2 station or below, compared with either forceps or vacuum delivery, CD was associated with more maternal infections and fewer perineal lacerations. Neonatal composite morbidity was not significantly different among the 3 routes of operative delivery.³⁰

Amnioinfusion for repetitive variable decelerations of the fetal heart rate may reduce the risk of CD for an indeterminate fetal heart-rate pattern.³¹

IOL in a well-dated pregnancy at 41 weeks will reduce the risk of CD. In a large clinical trial, 3,407 women at 41 weeks of gestation were randomly assigned to IOL or expectant management. The rate of CD was significantly lower in the women assigned to IOL compared with expectant management (21% vs 25%, respectively; P = .03).³² The rate of neonatal morbidity was similar in the 2 groups.

Women with twin gestations and the first twin in a cephalic presentation may elect vaginal delivery. In a large clinical trial, 1,398 women with a twin gestation and the first twin in a cephalic presentation were randomly assigned to planned vaginal delivery (with cesarean only if necessary) or planned CD.³³ The rate of CD was 44% and 91% for the women in the planned-vaginal and planned-cesarean groups, respectively. There was no significant difference in composite fetal or neonatal death or serious morbidity. The authors concluded that, for twin pregnancy with the presenting twin in the cephalic presentation, there were no demonstrated benefits of planned CD.

Develop maternity care systems that encourage the use of trial of labor after cesarean (TOLAC). The ACOG/SMFM guidelines focus on interventions to reduce the rate of primary CD and do not address the role of TOLAC in reducing CD rates. There are little data from clinical trials to assess the benefits and harms from TOLAC versus scheduled repeat CD.³⁴ However, our experience with TOLAC in the 1990s strongly suggests that encouraging TOLAC will decrease the rate of CD. In 1996 the US rate of vaginal birth after cesarean (VBAC) peaked at 28%, and the rate of CD achieved a recent historic nadir of 21%. Growing concerns that TOLAC occasionally results in fetal harm was followed by a decrease in the VBAC rate to 12% in 2015.¹ A recent study of obstetric practices in countries with high and low VBAC rates concluded that patient and clinician commitment and comfort with prioritizing TOLAC over scheduled repeat CD greatly influenced the VBAC rate.³⁵

Related article:
Should lower uterine segment thickness measurement be included in the TOLAC decision-making process?

Labor management is an art

During labor obstetricians must balance the unique needs of mother and fetus, which requires great clinical skill and patience. Evolving concepts of normal labor progress necessitate that we change our expectations concerning the acceptable rate of progress in the 1st and 2nd stage of labor. Consistent application of these new labor guidelines may help to reduce the rate of CD.

Share your thoughts! Send your Letter to the Editor to rbarbieri@frontlinemedcom.com. Please include your name and the city and state in which you practice.

During the past 45 years, the cesarean delivery (CD) rate in the United States has increased from 5.5% in 1970 to 33% from 2009 to 2013, followed by a small decrease to 32% in 2014 and 2015.¹ Many clinical problems cause clinicians and patients to decide that CD is an optimal birth route, including: abnormal labor progress, abnormal or indeterminate fetal heart rate pattern, breech presentation, multiple gestation, macrosomia, placental and cord abnormalities, preeclampsia, prior uterine surgery, and prior CD.² Recent secular trends that contribute to the current rate of CD include an adversarial liability environment,^3,4 increasing rates of maternal obesity,⁵ and widespread use of continuous fetal-heart monitoring during labor.⁶

Wide variation in CD rate has been reported among countries, states, and hospitals. The variation is due, in part, to different perspectives about balancing the harms and benefits of vaginal delivery versus CD. In Europe, in 2010 the CD rates in Sweden and Italy were 17.1% and 38%, respectively.⁷ In 2010, among the states, Alaska had the lowest rate of CD at 22% and Kentucky had the highest rate at 40%.⁸ In 2015, the highest rate was 38%, in Mississippi (FIGURE).⁹ In 2014, among Massachusetts hospitals with more than 2,500 births, the CD rate ranged from a low of 22% to a high of 37%.¹⁰

Clinicians, patients, policy experts, and the media are perplexed and troubled by the “high” US CD rate and the major variation in rate among countries, states, and hospitals. Labor management practices likely influence the rate of CD and diverse approaches to labor management likely account for the wide variation in CD rates.

A nationwide effort to standardize and continuously improve labor management might result in a decrease in the CD rate. Building on this opportunity, the American College of Obstetricians and Gynecologists (ACOG) and the Society of Maternal-Fetal Medicine (SMFM) have jointly recommended new labor management guidelines that may reduce the primary CD rate.⁸

The ACOG/SMFM guidelines encourage obstetricians to extend the time for labor progress in both the 1st and 2nd stages prior to recommending a CD.⁸ These new guidelines emphasize that for a modern obstetrician, patience is a virtue. There are 2 important caveats to this statement: to safely extend the length of time of labor requires both (1) a reassuring fetal heart rate tracing and (2) stable maternal health. If the fetus demonstrates a persistent worrisome Category II or a Category IIIheart-rate tracing, decisive intervention is necessary and permitting an extended labor would not be optimal. Similarly, if the mother has rapidly worsening preeclampsia it may not be wise to extend an induction of labor (IOL) over many days.

There are risks with extending the length of labor. An extended duration of the 1st stage of labor is associated with an increased rate of maternal chorioamnionitis and shoulder dystocia at birth.¹¹ An extended duration of the 2nd stage of labor is associated with an increase in the rate of maternal chorioamnionitis, anal sphincter injury, uterine atony, and neonatal admission to an intensive care unit.¹² Clinicians who adopt practices that permit an extended length of labor must weigh the benefits of avoiding a CD against these maternal and fetal complications.

Active phase redefined

Central to the ACOG/SMFM guidelines is a new definition of the active phase of labor. The research of Dr. Emmanuel Friedman indicated that at approximately 4 cm of cervical dilation many women in labor transition from the latent phase, a time of slow change in cervical dilation, to the active phase, a time of more rapid change in cervical dilation.^13,14 However, more recent research indicates that the transition between the latent and active phase is difficult to precisely define, but more often occurs at about 6 cm of cervical dilation and not 4 cm of dilation.¹⁵ Adopting these new norms means that laboring women will spend much more time in the latent phase, a phase of labor in which patience is a virtue.

The ACOG/SMFM guidelines

Main takeaways from the ACOG/SMFM guidelines are summarized below. Interventions that address common obstetric issues and labor abnormalities are outlined below.

Do not perform CD for a prolonged latent phase of labor, defined as regular contractions of >20 hours duration in nulliparous women and >14 hours duration in multiparous women. Patience with a prolonged latent phase will be rewarded by the majority of women entering the active phase of labor. Alternatively, if appropriate, cervical ripening followed by oxytocin IOL and amniotomy will help the patient with a prolonged latent phase to enter the active phase of labor.¹⁶

For women with an unfavorable cervix as assessed by the Bishop score, cervical ripening should be performed prior to IOL. Use of cervical ripening prior to IOL increases the chance of achieving vaginal delivery within 24 hours and may result in a modest decrease in the rate of CD.^17,18

Related article:
Should oxytocin and a Foley catheter be used concurrently for cervical ripening in induction of labor?
 

Failed IOL in the latent phase should only be diagnosed following 12 to 18 hours of both ruptured membranes and adequate contractions stimulated with oxytocin. The key ingredients for the successful management of the latent phase of labor are patience, oxytocin, and amniotomy.¹⁶

CD for the indication of active phase arrest requires cervical dilation ≥6 cm with ruptured membranes and no change in cervical dilation for ≥4 hours of adequate uterine activity. In the past, most obstetricians defined active phase arrest, a potential indication for CD, as the absence of cervical change for 2 or more hours in the presence of adequate uterine contractions and cervical dilation of at least 4 cm. Given the new definition of active phase arrest, slow but progressive progress in the 1st stage of labor is not an indication for CD.^11,19

“A specific absolute maximum length of time spent in the 2nd stage beyond which all women should be offered an operative delivery has not been identified.”⁸ Diagnosis of arrest of labor in the 2nd stage may be considered after at least 2 hours of pushing in multiparous women and 3 hours of pushing in nulliparous women, especially if no fetal descent is occurring. The guidelines also state “longer durations may be appropriate on an individualized basis (eg, with use of epidural analgesia or with fetal malposition)” as long as fetal descent is observed.

Patience is a virtue, especially in the management of the 2nd stage of labor. Extending the 2nd stage up to 4 hours appears to be reasonably safe if the fetal status is reassuring and the mother is physiologically stable. In a study from San Francisco of 42,268 births with normal newborn outcomes, the 95th percentile for the length of the 2nd stage of labor for nulliparous women was 3.3 hours without an epidural and 5.6 hours with an epidural.²⁰

In a study of 53,285 births, longer duration of pushing was associated with a small increase in the rate of neonatal adverse outcomes. In nulliparous women the rate of adverse neonatal outcomes increased from 1.3% with less than 60 minutes of pushing to 2.4% with greater than 240 minutes of pushing. Remarkably, even after 4 hours of pushing, 78% of nulliparous women who continued to push had a vaginal delivery.²¹ In this study, among nulliparous women the rate of anal sphincter injury increased from 5% with less than 60 minutes of pushing to 16% with greater than 240 minutes of pushing, and the rate of postpartum hemorrhage increased from 1% with less than 60 minutes of pushing to 3.3% with greater than 240 minutes of pushing.

I am not enthusiastic about patiently watching a labor extend into the 5th hour of the 2nd stage, especially if the fetus is at +2 station or lower. In a nulliparous woman, after 4 hours of managing the 2nd stage of labor, my patience is exhausted and I am inclined to identify a clear plan for delivery, either by enhanced labor coaching, operative vaginal delivery, or CD.

Operative vaginal delivery in the 2nd stage of labor is an acceptable alternative to CD. The rate of operative vaginal delivery in the United States has declined over the past 2 decades (TABLE). In Sweden in 2010 the operative vaginal delivery rate was 7.6% with a CD rate of 17.1%.⁷ In the United States in 2010 the operative delivery rate was 3.6%, and the CD rate was 33%.¹ A renewed focus on operative vaginal delivery with ongoing training and team simulation for the procedure would increase our use of operative delivery and decrease the overall rate of CD.

Related article:
STOP using instruments to assist with delivery of the head at cesarean
 

Encourage the detection of persistent fetal occiput posterior position by physical examination and/or ultrasound and consider manual rotation of the fetal occiput from the posterior to anterior position in the 2nd stage. Persistent occiput posterior is the most common fetal malposition.²² This malposition is associated with an increased rate of CD.²³ There are few randomized trials of manual rotation of the fetal occiput from posterior to anterior position in the 2nd stage of labor, and the evidence is insufficient to determine the efficacy of manual rotation.²⁴ Small nonrandomized studies report that manual rotation of the occiput from posterior to anterior position may reduce the CD rate.^25–27

For persistent 2nd stage fetal occiput posterior position in a woman with an adequate pelvis, where manual rotation was not successful and the fetus is at +2 station or below, operative vaginal delivery is an option. “Vacuum or forceps?” and “If forceps, to rotate or not to rotate?” those are the clinical questions. Forceps delivery is more likely to be successfulthan vacuum delivery.²⁸ Direct forceps delivery of the occiput posterior fetus is associated with more anal sphincter injuries than forceps delivery after successful rotation, but few clinicians regularly perform rotational forceps.²⁹ In a study of 2,351 women in the 2nd stage of labor with the fetus at +2 station or below, compared with either forceps or vacuum delivery, CD was associated with more maternal infections and fewer perineal lacerations. Neonatal composite morbidity was not significantly different among the 3 routes of operative delivery.³⁰

Amnioinfusion for repetitive variable decelerations of the fetal heart rate may reduce the risk of CD for an indeterminate fetal heart-rate pattern.³¹

IOL in a well-dated pregnancy at 41 weeks will reduce the risk of CD. In a large clinical trial, 3,407 women at 41 weeks of gestation were randomly assigned to IOL or expectant management. The rate of CD was significantly lower in the women assigned to IOL compared with expectant management (21% vs 25%, respectively; P = .03).³² The rate of neonatal morbidity was similar in the 2 groups.

Women with twin gestations and the first twin in a cephalic presentation may elect vaginal delivery. In a large clinical trial, 1,398 women with a twin gestation and the first twin in a cephalic presentation were randomly assigned to planned vaginal delivery (with cesarean only if necessary) or planned CD.³³ The rate of CD was 44% and 91% for the women in the planned-vaginal and planned-cesarean groups, respectively. There was no significant difference in composite fetal or neonatal death or serious morbidity. The authors concluded that, for twin pregnancy with the presenting twin in the cephalic presentation, there were no demonstrated benefits of planned CD.

Develop maternity care systems that encourage the use of trial of labor after cesarean (TOLAC). The ACOG/SMFM guidelines focus on interventions to reduce the rate of primary CD and do not address the role of TOLAC in reducing CD rates. There are little data from clinical trials to assess the benefits and harms from TOLAC versus scheduled repeat CD.³⁴ However, our experience with TOLAC in the 1990s strongly suggests that encouraging TOLAC will decrease the rate of CD. In 1996 the US rate of vaginal birth after cesarean (VBAC) peaked at 28%, and the rate of CD achieved a recent historic nadir of 21%. Growing concerns that TOLAC occasionally results in fetal harm was followed by a decrease in the VBAC rate to 12% in 2015.¹ A recent study of obstetric practices in countries with high and low VBAC rates concluded that patient and clinician commitment and comfort with prioritizing TOLAC over scheduled repeat CD greatly influenced the VBAC rate.³⁵

Related article:
Should lower uterine segment thickness measurement be included in the TOLAC decision-making process?

Labor management is an art

During labor obstetricians must balance the unique needs of mother and fetus, which requires great clinical skill and patience. Evolving concepts of normal labor progress necessitate that we change our expectations concerning the acceptable rate of progress in the 1st and 2nd stage of labor. Consistent application of these new labor guidelines may help to reduce the rate of CD.

Share your thoughts! Send your Letter to the Editor to rbarbieri@frontlinemedcom.com. Please include your name and the city and state in which you practice.

During the past 45 years, the cesarean delivery (CD) rate in the United States has increased from 5.5% in 1970 to 33% from 2009 to 2013, followed by a small decrease to 32% in 2014 and 2015.¹ Many clinical problems cause clinicians and patients to decide that CD is an optimal birth route, including: abnormal labor progress, abnormal or indeterminate fetal heart rate pattern, breech presentation, multiple gestation, macrosomia, placental and cord abnormalities, preeclampsia, prior uterine surgery, and prior CD.² Recent secular trends that contribute to the current rate of CD include an adversarial liability environment,^3,4 increasing rates of maternal obesity,⁵ and widespread use of continuous fetal-heart monitoring during labor.⁶

Wide variation in CD rate has been reported among countries, states, and hospitals. The variation is due, in part, to different perspectives about balancing the harms and benefits of vaginal delivery versus CD. In Europe, in 2010 the CD rates in Sweden and Italy were 17.1% and 38%, respectively.⁷ In 2010, among the states, Alaska had the lowest rate of CD at 22% and Kentucky had the highest rate at 40%.⁸ In 2015, the highest rate was 38%, in Mississippi (FIGURE).⁹ In 2014, among Massachusetts hospitals with more than 2,500 births, the CD rate ranged from a low of 22% to a high of 37%.¹⁰

Clinicians, patients, policy experts, and the media are perplexed and troubled by the “high” US CD rate and the major variation in rate among countries, states, and hospitals. Labor management practices likely influence the rate of CD and diverse approaches to labor management likely account for the wide variation in CD rates.

A nationwide effort to standardize and continuously improve labor management might result in a decrease in the CD rate. Building on this opportunity, the American College of Obstetricians and Gynecologists (ACOG) and the Society of Maternal-Fetal Medicine (SMFM) have jointly recommended new labor management guidelines that may reduce the primary CD rate.⁸

The ACOG/SMFM guidelines encourage obstetricians to extend the time for labor progress in both the 1st and 2nd stages prior to recommending a CD.⁸ These new guidelines emphasize that for a modern obstetrician, patience is a virtue. There are 2 important caveats to this statement: to safely extend the length of time of labor requires both (1) a reassuring fetal heart rate tracing and (2) stable maternal health. If the fetus demonstrates a persistent worrisome Category II or a Category IIIheart-rate tracing, decisive intervention is necessary and permitting an extended labor would not be optimal. Similarly, if the mother has rapidly worsening preeclampsia it may not be wise to extend an induction of labor (IOL) over many days.

There are risks with extending the length of labor. An extended duration of the 1st stage of labor is associated with an increased rate of maternal chorioamnionitis and shoulder dystocia at birth.¹¹ An extended duration of the 2nd stage of labor is associated with an increase in the rate of maternal chorioamnionitis, anal sphincter injury, uterine atony, and neonatal admission to an intensive care unit.¹² Clinicians who adopt practices that permit an extended length of labor must weigh the benefits of avoiding a CD against these maternal and fetal complications.

Active phase redefined

Central to the ACOG/SMFM guidelines is a new definition of the active phase of labor. The research of Dr. Emmanuel Friedman indicated that at approximately 4 cm of cervical dilation many women in labor transition from the latent phase, a time of slow change in cervical dilation, to the active phase, a time of more rapid change in cervical dilation.^13,14 However, more recent research indicates that the transition between the latent and active phase is difficult to precisely define, but more often occurs at about 6 cm of cervical dilation and not 4 cm of dilation.¹⁵ Adopting these new norms means that laboring women will spend much more time in the latent phase, a phase of labor in which patience is a virtue.

The ACOG/SMFM guidelines

Main takeaways from the ACOG/SMFM guidelines are summarized below. Interventions that address common obstetric issues and labor abnormalities are outlined below.

Do not perform CD for a prolonged latent phase of labor, defined as regular contractions of >20 hours duration in nulliparous women and >14 hours duration in multiparous women. Patience with a prolonged latent phase will be rewarded by the majority of women entering the active phase of labor. Alternatively, if appropriate, cervical ripening followed by oxytocin IOL and amniotomy will help the patient with a prolonged latent phase to enter the active phase of labor.¹⁶

For women with an unfavorable cervix as assessed by the Bishop score, cervical ripening should be performed prior to IOL. Use of cervical ripening prior to IOL increases the chance of achieving vaginal delivery within 24 hours and may result in a modest decrease in the rate of CD.^17,18

Related article:
Should oxytocin and a Foley catheter be used concurrently for cervical ripening in induction of labor?
 

Failed IOL in the latent phase should only be diagnosed following 12 to 18 hours of both ruptured membranes and adequate contractions stimulated with oxytocin. The key ingredients for the successful management of the latent phase of labor are patience, oxytocin, and amniotomy.¹⁶

CD for the indication of active phase arrest requires cervical dilation ≥6 cm with ruptured membranes and no change in cervical dilation for ≥4 hours of adequate uterine activity. In the past, most obstetricians defined active phase arrest, a potential indication for CD, as the absence of cervical change for 2 or more hours in the presence of adequate uterine contractions and cervical dilation of at least 4 cm. Given the new definition of active phase arrest, slow but progressive progress in the 1st stage of labor is not an indication for CD.^11,19

“A specific absolute maximum length of time spent in the 2nd stage beyond which all women should be offered an operative delivery has not been identified.”⁸ Diagnosis of arrest of labor in the 2nd stage may be considered after at least 2 hours of pushing in multiparous women and 3 hours of pushing in nulliparous women, especially if no fetal descent is occurring. The guidelines also state “longer durations may be appropriate on an individualized basis (eg, with use of epidural analgesia or with fetal malposition)” as long as fetal descent is observed.

Patience is a virtue, especially in the management of the 2nd stage of labor. Extending the 2nd stage up to 4 hours appears to be reasonably safe if the fetal status is reassuring and the mother is physiologically stable. In a study from San Francisco of 42,268 births with normal newborn outcomes, the 95th percentile for the length of the 2nd stage of labor for nulliparous women was 3.3 hours without an epidural and 5.6 hours with an epidural.²⁰

In a study of 53,285 births, longer duration of pushing was associated with a small increase in the rate of neonatal adverse outcomes. In nulliparous women the rate of adverse neonatal outcomes increased from 1.3% with less than 60 minutes of pushing to 2.4% with greater than 240 minutes of pushing. Remarkably, even after 4 hours of pushing, 78% of nulliparous women who continued to push had a vaginal delivery.²¹ In this study, among nulliparous women the rate of anal sphincter injury increased from 5% with less than 60 minutes of pushing to 16% with greater than 240 minutes of pushing, and the rate of postpartum hemorrhage increased from 1% with less than 60 minutes of pushing to 3.3% with greater than 240 minutes of pushing.

I am not enthusiastic about patiently watching a labor extend into the 5th hour of the 2nd stage, especially if the fetus is at +2 station or lower. In a nulliparous woman, after 4 hours of managing the 2nd stage of labor, my patience is exhausted and I am inclined to identify a clear plan for delivery, either by enhanced labor coaching, operative vaginal delivery, or CD.

Operative vaginal delivery in the 2nd stage of labor is an acceptable alternative to CD. The rate of operative vaginal delivery in the United States has declined over the past 2 decades (TABLE). In Sweden in 2010 the operative vaginal delivery rate was 7.6% with a CD rate of 17.1%.⁷ In the United States in 2010 the operative delivery rate was 3.6%, and the CD rate was 33%.¹ A renewed focus on operative vaginal delivery with ongoing training and team simulation for the procedure would increase our use of operative delivery and decrease the overall rate of CD.

Related article:
STOP using instruments to assist with delivery of the head at cesarean
 

Encourage the detection of persistent fetal occiput posterior position by physical examination and/or ultrasound and consider manual rotation of the fetal occiput from the posterior to anterior position in the 2nd stage. Persistent occiput posterior is the most common fetal malposition.²² This malposition is associated with an increased rate of CD.²³ There are few randomized trials of manual rotation of the fetal occiput from posterior to anterior position in the 2nd stage of labor, and the evidence is insufficient to determine the efficacy of manual rotation.²⁴ Small nonrandomized studies report that manual rotation of the occiput from posterior to anterior position may reduce the CD rate.^25–27

For persistent 2nd stage fetal occiput posterior position in a woman with an adequate pelvis, where manual rotation was not successful and the fetus is at +2 station or below, operative vaginal delivery is an option. “Vacuum or forceps?” and “If forceps, to rotate or not to rotate?” those are the clinical questions. Forceps delivery is more likely to be successfulthan vacuum delivery.²⁸ Direct forceps delivery of the occiput posterior fetus is associated with more anal sphincter injuries than forceps delivery after successful rotation, but few clinicians regularly perform rotational forceps.²⁹ In a study of 2,351 women in the 2nd stage of labor with the fetus at +2 station or below, compared with either forceps or vacuum delivery, CD was associated with more maternal infections and fewer perineal lacerations. Neonatal composite morbidity was not significantly different among the 3 routes of operative delivery.³⁰

Amnioinfusion for repetitive variable decelerations of the fetal heart rate may reduce the risk of CD for an indeterminate fetal heart-rate pattern.³¹

IOL in a well-dated pregnancy at 41 weeks will reduce the risk of CD. In a large clinical trial, 3,407 women at 41 weeks of gestation were randomly assigned to IOL or expectant management. The rate of CD was significantly lower in the women assigned to IOL compared with expectant management (21% vs 25%, respectively; P = .03).³² The rate of neonatal morbidity was similar in the 2 groups.

Women with twin gestations and the first twin in a cephalic presentation may elect vaginal delivery. In a large clinical trial, 1,398 women with a twin gestation and the first twin in a cephalic presentation were randomly assigned to planned vaginal delivery (with cesarean only if necessary) or planned CD.³³ The rate of CD was 44% and 91% for the women in the planned-vaginal and planned-cesarean groups, respectively. There was no significant difference in composite fetal or neonatal death or serious morbidity. The authors concluded that, for twin pregnancy with the presenting twin in the cephalic presentation, there were no demonstrated benefits of planned CD.

Develop maternity care systems that encourage the use of trial of labor after cesarean (TOLAC). The ACOG/SMFM guidelines focus on interventions to reduce the rate of primary CD and do not address the role of TOLAC in reducing CD rates. There are little data from clinical trials to assess the benefits and harms from TOLAC versus scheduled repeat CD.³⁴ However, our experience with TOLAC in the 1990s strongly suggests that encouraging TOLAC will decrease the rate of CD. In 1996 the US rate of vaginal birth after cesarean (VBAC) peaked at 28%, and the rate of CD achieved a recent historic nadir of 21%. Growing concerns that TOLAC occasionally results in fetal harm was followed by a decrease in the VBAC rate to 12% in 2015.¹ A recent study of obstetric practices in countries with high and low VBAC rates concluded that patient and clinician commitment and comfort with prioritizing TOLAC over scheduled repeat CD greatly influenced the VBAC rate.³⁵

Related article:
Should lower uterine segment thickness measurement be included in the TOLAC decision-making process?

Labor management is an art

During labor obstetricians must balance the unique needs of mother and fetus, which requires great clinical skill and patience. Evolving concepts of normal labor progress necessitate that we change our expectations concerning the acceptable rate of progress in the 1st and 2nd stage of labor. Consistent application of these new labor guidelines may help to reduce the rate of CD.

Share your thoughts! Send your Letter to the Editor to rbarbieri@frontlinemedcom.com. Please include your name and the city and state in which you practice.

DIAGNOSE HERPES SIMPLEX VIRUS

According to the CDC, infections with HSV-2 affect more than 24 million Americans. Patients with HSV-2 strain are at increased risk for contracting and transmitting HIV. Pregnant women infected with HSV-2 are at risk of transmitting the virus to their babies, with increased risk for neurologic complications in the child. 

FOR MORE INFORMATION, VISIT: http://www.hologic.com/search/site/aptima%20hsv

PRECISELY TARGET TISSUE DURING LUMPECTOMY OR BIOPSY

Cianna Medical reported recent data showing that, when compared with wire localization, the SCOUT reduces breast surgery operating room (OR) delay times by 72.5%, resulted in an average 29- minute reduction in OR waiting time, and significantly improved workflow efficiency.

FOR MORE INFORMATION, VISIT: https://www.ciannamedical.com/savi-scout/

PLASMA HYSTEROSCOPIC RESECTION

During gynecologic procedures, the Olympus 8.5-mm hystero-resectoscope uses a combination of radio frequency, energy, and saline to create plasma, an electrically conductive gas cloud of vapor and charged particles. Due to its conductivity, plasma allows energy to cross into targeted tissue at lower energy levels than with more traditional approaches. This effect leads to lower operating temperatures and therefore less thermal spread.

FOR MORE INFORMATION, VISIT:  http://olympusmedical.com.sg

APP-BASED HANDHELD ULTRASOUND

High-resolution images can be saved, reviewed, and managed on the secure Clarius Cloud. Built with a durable magnesium shell, each device has an IPX7 immersion rating so it can be sterilized. Power is obtained from a rechargeable battery that will last for more than 45 minutes of scanning; 2 batteries come with each Clarius device.

FOR MORE INFORMATION, VISIT: https://www.clarius.me/

Share your thoughts! Send your Letter to the Editor to rbarbieri@frontlinemedcom.com. Please include your name and the city and state in which you practice.

DIAGNOSE HERPES SIMPLEX VIRUS

According to the CDC, infections with HSV-2 affect more than 24 million Americans. Patients with HSV-2 strain are at increased risk for contracting and transmitting HIV. Pregnant women infected with HSV-2 are at risk of transmitting the virus to their babies, with increased risk for neurologic complications in the child. 

FOR MORE INFORMATION, VISIT: http://www.hologic.com/search/site/aptima%20hsv

PRECISELY TARGET TISSUE DURING LUMPECTOMY OR BIOPSY

Cianna Medical reported recent data showing that, when compared with wire localization, the SCOUT reduces breast surgery operating room (OR) delay times by 72.5%, resulted in an average 29- minute reduction in OR waiting time, and significantly improved workflow efficiency.

FOR MORE INFORMATION, VISIT: https://www.ciannamedical.com/savi-scout/

PLASMA HYSTEROSCOPIC RESECTION

During gynecologic procedures, the Olympus 8.5-mm hystero-resectoscope uses a combination of radio frequency, energy, and saline to create plasma, an electrically conductive gas cloud of vapor and charged particles. Due to its conductivity, plasma allows energy to cross into targeted tissue at lower energy levels than with more traditional approaches. This effect leads to lower operating temperatures and therefore less thermal spread.

FOR MORE INFORMATION, VISIT:  http://olympusmedical.com.sg

APP-BASED HANDHELD ULTRASOUND

High-resolution images can be saved, reviewed, and managed on the secure Clarius Cloud. Built with a durable magnesium shell, each device has an IPX7 immersion rating so it can be sterilized. Power is obtained from a rechargeable battery that will last for more than 45 minutes of scanning; 2 batteries come with each Clarius device.

FOR MORE INFORMATION, VISIT: https://www.clarius.me/

Share your thoughts! Send your Letter to the Editor to rbarbieri@frontlinemedcom.com. Please include your name and the city and state in which you practice.

DIAGNOSE HERPES SIMPLEX VIRUS

According to the CDC, infections with HSV-2 affect more than 24 million Americans. Patients with HSV-2 strain are at increased risk for contracting and transmitting HIV. Pregnant women infected with HSV-2 are at risk of transmitting the virus to their babies, with increased risk for neurologic complications in the child. 

FOR MORE INFORMATION, VISIT: http://www.hologic.com/search/site/aptima%20hsv

PRECISELY TARGET TISSUE DURING LUMPECTOMY OR BIOPSY

Cianna Medical reported recent data showing that, when compared with wire localization, the SCOUT reduces breast surgery operating room (OR) delay times by 72.5%, resulted in an average 29- minute reduction in OR waiting time, and significantly improved workflow efficiency.

FOR MORE INFORMATION, VISIT: https://www.ciannamedical.com/savi-scout/

PLASMA HYSTEROSCOPIC RESECTION

During gynecologic procedures, the Olympus 8.5-mm hystero-resectoscope uses a combination of radio frequency, energy, and saline to create plasma, an electrically conductive gas cloud of vapor and charged particles. Due to its conductivity, plasma allows energy to cross into targeted tissue at lower energy levels than with more traditional approaches. This effect leads to lower operating temperatures and therefore less thermal spread.

FOR MORE INFORMATION, VISIT:  http://olympusmedical.com.sg

APP-BASED HANDHELD ULTRASOUND

High-resolution images can be saved, reviewed, and managed on the secure Clarius Cloud. Built with a durable magnesium shell, each device has an IPX7 immersion rating so it can be sterilized. Power is obtained from a rechargeable battery that will last for more than 45 minutes of scanning; 2 batteries come with each Clarius device.

FOR MORE INFORMATION, VISIT: https://www.clarius.me/

Share your thoughts! Send your Letter to the Editor to rbarbieri@frontlinemedcom.com. Please include your name and the city and state in which you practice.

A) Mirena or Liletta (52 mg LNG-IUD) CORRECT
Mirena (Bayer) and Liletta (Allergan) are progestin-releasing intrauterine devices (IUDs) of similar size and shape. On ultrasonography, both the arms and the distal tip are echogenic. The progestin-containing plastic sleeve surrounding the stem in the middle demonstrates a laminated acoustic shadowing with distinctive parallel lines.^1–4

B) Small-framed LNG-IUDs: Skyla (13.5 mg) or Kyleena (19.5 mg) INCORRECT
Skyla (Bayer) and Kyleena (Bayer) are small-framed LNG-IUDs. The ultrasound appearance of Skyla (LNG 13.5 mg) is similar to that of Mirena but has a markedly echogenic silver ring superiorly just below the crossbar, best seen with 2D (sagittal) views but also imaged with 3D ultrasound.^1,2,5

The Kyleena device (LNG 19.5 mg) uses the same smaller T-shaped frame and metal ring, but the plastic sleeve is longer to accommodate the greater quantity of progestin.⁶

C) Paragard (intrauterine copper contraceptive) INCORRECT
Paragard (Teva Women’s Health) is a nonhormonal IUD containing copper wire wrapped around its stem and solid copper bands on each crossbar. On ultrasonography, the stem is uniformly and markedly echogenic due to the copper wire.^1,2,7

A) Mirena or Liletta (52 mg LNG-IUD) CORRECT
Mirena (Bayer) and Liletta (Allergan) are progestin-releasing intrauterine devices (IUDs) of similar size and shape. On ultrasonography, both the arms and the distal tip are echogenic. The progestin-containing plastic sleeve surrounding the stem in the middle demonstrates a laminated acoustic shadowing with distinctive parallel lines.^1–4

B) Small-framed LNG-IUDs: Skyla (13.5 mg) or Kyleena (19.5 mg) INCORRECT
Skyla (Bayer) and Kyleena (Bayer) are small-framed LNG-IUDs. The ultrasound appearance of Skyla (LNG 13.5 mg) is similar to that of Mirena but has a markedly echogenic silver ring superiorly just below the crossbar, best seen with 2D (sagittal) views but also imaged with 3D ultrasound.^1,2,5

The Kyleena device (LNG 19.5 mg) uses the same smaller T-shaped frame and metal ring, but the plastic sleeve is longer to accommodate the greater quantity of progestin.⁶

C) Paragard (intrauterine copper contraceptive) INCORRECT
Paragard (Teva Women’s Health) is a nonhormonal IUD containing copper wire wrapped around its stem and solid copper bands on each crossbar. On ultrasonography, the stem is uniformly and markedly echogenic due to the copper wire.^1,2,7

A) Mirena or Liletta (52 mg LNG-IUD) CORRECT
Mirena (Bayer) and Liletta (Allergan) are progestin-releasing intrauterine devices (IUDs) of similar size and shape. On ultrasonography, both the arms and the distal tip are echogenic. The progestin-containing plastic sleeve surrounding the stem in the middle demonstrates a laminated acoustic shadowing with distinctive parallel lines.^1–4

B) Small-framed LNG-IUDs: Skyla (13.5 mg) or Kyleena (19.5 mg) INCORRECT
Skyla (Bayer) and Kyleena (Bayer) are small-framed LNG-IUDs. The ultrasound appearance of Skyla (LNG 13.5 mg) is similar to that of Mirena but has a markedly echogenic silver ring superiorly just below the crossbar, best seen with 2D (sagittal) views but also imaged with 3D ultrasound.^1,2,5

The Kyleena device (LNG 19.5 mg) uses the same smaller T-shaped frame and metal ring, but the plastic sleeve is longer to accommodate the greater quantity of progestin.⁶

C) Paragard (intrauterine copper contraceptive) INCORRECT
Paragard (Teva Women’s Health) is a nonhormonal IUD containing copper wire wrapped around its stem and solid copper bands on each crossbar. On ultrasonography, the stem is uniformly and markedly echogenic due to the copper wire.^1,2,7

Click Here to Access Handout.

 Your patients may be overwhelmed with so many decisions as they prepare for their newborn to arrive. We want to help make one decision easier. The Cord Blood and Cord Tissue Preservation Patient Handout provides simple and clear education about their cord blood and cord tissue preservation options.

Access and print the handout now and give it to your patients so they can review the information at their own pace.

Click Here to Access Handout.

Click Here to Access Handout.

 Your patients may be overwhelmed with so many decisions as they prepare for their newborn to arrive. We want to help make one decision easier. The Cord Blood and Cord Tissue Preservation Patient Handout provides simple and clear education about their cord blood and cord tissue preservation options.

Access and print the handout now and give it to your patients so they can review the information at their own pace.

Click Here to Access Handout.

Click Here to Access Handout.

 Your patients may be overwhelmed with so many decisions as they prepare for their newborn to arrive. We want to help make one decision easier. The Cord Blood and Cord Tissue Preservation Patient Handout provides simple and clear education about their cord blood and cord tissue preservation options.

Access and print the handout now and give it to your patients so they can review the information at their own pace.

Click Here to Access Handout.

Resources

• American Board of Obesity Medicine
• Obesity Medicine Association
• Obesity Society

Resources

• American Board of Obesity Medicine
• Obesity Medicine Association
• Obesity Society

Resources

• American Board of Obesity Medicine
• Obesity Medicine Association
• Obesity Society

Visit the Society of Gynecologic Surgeons online: sgsonline.org

More videos from SGS:  

• Near-infrared imaging in robotically-assisted urogynecologic surgery
• Advanced techniques in cystectomy for mature cystic teratomas
• Novel classification of labial anatomy and evaluation in the treatment of labial agglutination

Visit the Society of Gynecologic Surgeons online: sgsonline.org

More videos from SGS:  

• Near-infrared imaging in robotically-assisted urogynecologic surgery
• Advanced techniques in cystectomy for mature cystic teratomas
• Novel classification of labial anatomy and evaluation in the treatment of labial agglutination

Visit the Society of Gynecologic Surgeons online: sgsonline.org

More videos from SGS:  

• Near-infrared imaging in robotically-assisted urogynecologic surgery
• Advanced techniques in cystectomy for mature cystic teratomas
• Novel classification of labial anatomy and evaluation in the treatment of labial agglutination

Illustration: Kimberly Martens for OBG Management

Related article:
Endometriosis: Expert answers to 7 crucial questions on diagnosis

Etiology

Endometriomas are extensively described in the literature, and their origin is the subject of several theories. In 1921, Sampson noted luteal membrane and ovarian epithelial tissues within endometriomas and was the first to indicate that endometriomas may result from the invasion of functional cysts by endometrial tissue.^2,4,5 In 1979, Czernobilsky and Morris⁶ found endometrial and oviduct-like epithelium in ovarian endometriosis and concluded that ovarian tissue may be a common histologic precursor. Several other authors subsequently have reported finding different types of tissue within ovarian endometriomas, and not all of these chocolate cysts showed histologic evidence of endometriosis.^4,7,8

Read about the classification of endometriomas

Disease classification

Our classification system identifies 2 types of endometriomas on the basis of their etiologies and characteristics. Type I, which arise from endometrial tissue implanted on the ovarian surface, are also called true endometriomas. Invagination of cortex and subsequent hemorrhage from endometrial tissue result in cyst formation. Endometrial tissue (endometrial stroma and glands) is histologically present in all type I endometriomas.^1,4,9 These endometriomas usually are small (<5 cm in diameter) and have a densely adherent fibrous capsule.⁴ Often, there is no clear plane between cyst wall and ovarian stroma.³

Type II endometriomas arise from functional cysts involved in or invaded by cortical or pelvic side-wall endometrial implants or by type I endometriomas. Type II endometriomas are subclassified by the extent of endometrial implant involvement in the cyst wall. Type IIA endometriomas are hemorrhagic cysts with less than 10% of endometrial tissue within the cyst wall. Similar to the functional cysts from which they originate, type IIA endometriomas have a cyst wall that is separated easily from ovarian tissue during surgery.^4,7,9 Although type II endometriomas tend to be larger than their type I counterparts, in some cases they are identified at an early stage of 2 to 5 cm. Endometriomas larger than 5 cm are almost always type II.⁴

Type IIB and IIC endometriomas have endometrial implants and fibrosis within their cyst walls, with progressively more endometrial invasion in type IIC endometriomas (>50%) than in type IIB (10% to 50%). Consequently, type IIB cysts are relatively easy to dissect from ovarian tissue, except adjacent to an endometriotic area where the cyst densely adheres to the ovarian stroma. In type IIC, endometrial tissue more extensively penetrates the capsule, making dissection of diseased tissue from the ovarian stroma more difficult; in fact, separating type IIC cyst wall from ovarian stroma can be as challenging as excising a type I endometrioma.⁷ In most cases, a type IIC cyst is attached by adhesions and fibrosis to the pelvic side wall or uterus and ruptures during mobilization (TABLE).

Related article:
Imaging the endometrioma and mature cystic teratoma

Presentation and diagnosis

Almost all patients with an endometrioma concurrently have peritoneal endometriosis, which is characterized by dysmenorrhea, dyspareunia, chronic pelvic pain, infertility, and, in some cases, gastrointestinal or genitourinary dysfunction.¹ Pelvic examination may reveal an adnexal mass that is an endometrioma, or an endometrioma may appear on imaging obtained in a pelvic pain or infertility work-up. Given its 73% sensitivity, 94% specificity, safety, and low cost, transvaginal ultrasonography is the preferred imaging modality for endometrioma.³ The characteristic ultrasonographic appearance is that of a round, homogeneous, fluid-filled mass with low-level echoes.¹ Magnetic resonance imaging is appropriate when a more sensitive imaging modality is indicated, as for a patient with risk factors for malignancy.^3,10–12

Read about the surgical management of endometriomas

Surgical management

Indications for surgical excision of endometriomas include pelvic pain, infertility, and prevention and diagnosis of malignancy. Endometriomas may be excised prior to use of assisted reproductive technology.^13–15 Medical therapy, such as oral contraceptives, can be used to reduce the size of endometriomas but does not improve fertility.³ Certain ovarian cancers are more common in women with endometriosis, and ovarian tumors are thought to develop in about 1% of ovarian endometriosis cases.^1,12 Therefore, endometrioma excision may reduce the risk of malignancy. As with other ovarian cysts, large endometriomas may be excised to reduce the risks of rupture and torsion.

Don't miss the video that accompanies this article!

---

To watch the authors perform laparoscopic excision of type I and type II endometriomas, click here

 

Approach

Laparoscopy is the preferred approach for endometrioma excision. Controversy exists regarding the ideal procedure: complete excision (with stripping of the cyst capsule) or drainage and ablation of the cyst wall. Compared with drainage and ablation, excision reduces recurrence of endometriomas; relieves dysmenorrhea, dyspareunia, pelvic pain, and other symptoms; and improves fertility.^13,16 The recurrence rate may be as low as 5.8% with complete excision but is 90% with simple transvaginal aspiration.^17,18 If not performed properly, however, cyst capsule stripping may damage nearby ovarian stroma and decrease the ovarian reserve.¹⁴ Some authors have advocated combining excision and ablation—performing cystectomy until there is no longer a clear plane between capsule and ovarian stroma and then ablating any remaining endometrial tissue.⁸

With type I and IIC endometriomas, we have seen the endometrial cyst wall infiltrating the ovarian stroma so deeply there is not always a definable plane. By contrast, type IIA and IIB endometriomas typically have a plane between the cyst wall and the ovarian cortex. In type II endometriomas, endometrial implants on the ovarian cortex infiltrate the plane of the cyst wall such that the juxtaposing lipomatous follicular cyst detaches with minimal intraoperative traction. Portions of type II endometriomas containing fibrosis and adhesions may become more difficult to peel off the cyst wall. For most endometriomas, at least 1 spot is difficult to peel off the ovary, and extra care must be taken at the hilum of ovary to avoid excising healthy ovarian cortex.^4,5,7,8

Our surgical approach accounts for the described variations in type I and II endometriomas. Endometrial contents often spill as the endometrioma is dissected off neighboring structures. When possible, endometriomas should be aspirated and irrigated prior to cystectomy to avoid seeding the pelvis and abdomen with spilled endometriotic contents. We use hydrodissection, the injection of dilute vasopressin with a laparoscopic needle, to create a plane between cyst wall and ovarian stroma and strip the cyst capsule with laparoscopic graspers. Type I endometriomas adhere densely to the ovary. Given the presence of fibrosis and adhesions, the cyst is excised in a piecemeal fashion. Care is taken to remove any endometrial implants from the ovary while preserving as much of the ovarian tissue as possible.¹

Type II endometriomas are larger cysts originating from the invasion of endometrial implants or type I endometrioma into functional cysts. The difficulty of capsule excision varies according to the extent of endometrial invasion. Type IIA endometriomas contain less than 10% endometrial tissue within the cyst capsule. Thus, the standard ovarian cystectomy stripping technique is successful in removing more than 90% of the cyst capsule. Special care is taken in stripping the residual small portion that involves the endometrial glands and stroma and adheres densely to the ovary.

The larger proportion of endometrial tissue present in type IIB and IIC endometriomas degrades the plane between the cyst capsule and the ovarian stroma, making excision more difficult. Similar to the type I excision, a piecemeal approach is often necessary. If complete stripping of the cyst capsule would result in extensive loss of healthy ovarian tissue, then electrocautery, plasma energy, or laser ablation can be selectively used to destroy focal areas of endometrial invasion. Complete ablation may be difficult, as the endometrioma wall can be up to 5 mm thick.¹⁹ For these thick-walled endometriomas, we recommend excision (vs ablation), which lowers the risk of endometrioma recurrence.

Related article:
Endometriosis and pain: Expert answers to 6 questions targeting your management options
 

Conclusion

Endometriomas, common adnexal masses in women affected by endometriosis, may exacerbate pelvic pain and impair fertility. Gynecologists should be prepared to excise endometriomas completely and exercise care in preserving as much of the ovarian stroma as possible. We classify endometriomas into 2 types: type I, which develop from invagination of endometrial implants in the ovarian cortex, and type II, which stem from invasion of functional cysts by endometrial implants or type I endometrioma. This distinction guides surgical management. We hope this article and its accompanying video will be helpful in guiding laparoscopic excision of type I and II endometriomas.

Share your thoughts! Send your Letter to the Editor to rbarbieri@frontlinemedcom.com. Please include your name and the city and state in which you practice.

Illustration: Kimberly Martens for OBG Management

Related article:
Endometriosis: Expert answers to 7 crucial questions on diagnosis

Etiology

Endometriomas are extensively described in the literature, and their origin is the subject of several theories. In 1921, Sampson noted luteal membrane and ovarian epithelial tissues within endometriomas and was the first to indicate that endometriomas may result from the invasion of functional cysts by endometrial tissue.^2,4,5 In 1979, Czernobilsky and Morris⁶ found endometrial and oviduct-like epithelium in ovarian endometriosis and concluded that ovarian tissue may be a common histologic precursor. Several other authors subsequently have reported finding different types of tissue within ovarian endometriomas, and not all of these chocolate cysts showed histologic evidence of endometriosis.^4,7,8

Read about the classification of endometriomas

Disease classification

Our classification system identifies 2 types of endometriomas on the basis of their etiologies and characteristics. Type I, which arise from endometrial tissue implanted on the ovarian surface, are also called true endometriomas. Invagination of cortex and subsequent hemorrhage from endometrial tissue result in cyst formation. Endometrial tissue (endometrial stroma and glands) is histologically present in all type I endometriomas.^1,4,9 These endometriomas usually are small (<5 cm in diameter) and have a densely adherent fibrous capsule.⁴ Often, there is no clear plane between cyst wall and ovarian stroma.³

Type II endometriomas arise from functional cysts involved in or invaded by cortical or pelvic side-wall endometrial implants or by type I endometriomas. Type II endometriomas are subclassified by the extent of endometrial implant involvement in the cyst wall. Type IIA endometriomas are hemorrhagic cysts with less than 10% of endometrial tissue within the cyst wall. Similar to the functional cysts from which they originate, type IIA endometriomas have a cyst wall that is separated easily from ovarian tissue during surgery.^4,7,9 Although type II endometriomas tend to be larger than their type I counterparts, in some cases they are identified at an early stage of 2 to 5 cm. Endometriomas larger than 5 cm are almost always type II.⁴

Type IIB and IIC endometriomas have endometrial implants and fibrosis within their cyst walls, with progressively more endometrial invasion in type IIC endometriomas (>50%) than in type IIB (10% to 50%). Consequently, type IIB cysts are relatively easy to dissect from ovarian tissue, except adjacent to an endometriotic area where the cyst densely adheres to the ovarian stroma. In type IIC, endometrial tissue more extensively penetrates the capsule, making dissection of diseased tissue from the ovarian stroma more difficult; in fact, separating type IIC cyst wall from ovarian stroma can be as challenging as excising a type I endometrioma.⁷ In most cases, a type IIC cyst is attached by adhesions and fibrosis to the pelvic side wall or uterus and ruptures during mobilization (TABLE).

Related article:
Imaging the endometrioma and mature cystic teratoma

Presentation and diagnosis

Almost all patients with an endometrioma concurrently have peritoneal endometriosis, which is characterized by dysmenorrhea, dyspareunia, chronic pelvic pain, infertility, and, in some cases, gastrointestinal or genitourinary dysfunction.¹ Pelvic examination may reveal an adnexal mass that is an endometrioma, or an endometrioma may appear on imaging obtained in a pelvic pain or infertility work-up. Given its 73% sensitivity, 94% specificity, safety, and low cost, transvaginal ultrasonography is the preferred imaging modality for endometrioma.³ The characteristic ultrasonographic appearance is that of a round, homogeneous, fluid-filled mass with low-level echoes.¹ Magnetic resonance imaging is appropriate when a more sensitive imaging modality is indicated, as for a patient with risk factors for malignancy.^3,10–12

Read about the surgical management of endometriomas

Surgical management

Indications for surgical excision of endometriomas include pelvic pain, infertility, and prevention and diagnosis of malignancy. Endometriomas may be excised prior to use of assisted reproductive technology.^13–15 Medical therapy, such as oral contraceptives, can be used to reduce the size of endometriomas but does not improve fertility.³ Certain ovarian cancers are more common in women with endometriosis, and ovarian tumors are thought to develop in about 1% of ovarian endometriosis cases.^1,12 Therefore, endometrioma excision may reduce the risk of malignancy. As with other ovarian cysts, large endometriomas may be excised to reduce the risks of rupture and torsion.

Don't miss the video that accompanies this article!

---

To watch the authors perform laparoscopic excision of type I and type II endometriomas, click here

 

Approach

Laparoscopy is the preferred approach for endometrioma excision. Controversy exists regarding the ideal procedure: complete excision (with stripping of the cyst capsule) or drainage and ablation of the cyst wall. Compared with drainage and ablation, excision reduces recurrence of endometriomas; relieves dysmenorrhea, dyspareunia, pelvic pain, and other symptoms; and improves fertility.^13,16 The recurrence rate may be as low as 5.8% with complete excision but is 90% with simple transvaginal aspiration.^17,18 If not performed properly, however, cyst capsule stripping may damage nearby ovarian stroma and decrease the ovarian reserve.¹⁴ Some authors have advocated combining excision and ablation—performing cystectomy until there is no longer a clear plane between capsule and ovarian stroma and then ablating any remaining endometrial tissue.⁸

With type I and IIC endometriomas, we have seen the endometrial cyst wall infiltrating the ovarian stroma so deeply there is not always a definable plane. By contrast, type IIA and IIB endometriomas typically have a plane between the cyst wall and the ovarian cortex. In type II endometriomas, endometrial implants on the ovarian cortex infiltrate the plane of the cyst wall such that the juxtaposing lipomatous follicular cyst detaches with minimal intraoperative traction. Portions of type II endometriomas containing fibrosis and adhesions may become more difficult to peel off the cyst wall. For most endometriomas, at least 1 spot is difficult to peel off the ovary, and extra care must be taken at the hilum of ovary to avoid excising healthy ovarian cortex.^4,5,7,8

Our surgical approach accounts for the described variations in type I and II endometriomas. Endometrial contents often spill as the endometrioma is dissected off neighboring structures. When possible, endometriomas should be aspirated and irrigated prior to cystectomy to avoid seeding the pelvis and abdomen with spilled endometriotic contents. We use hydrodissection, the injection of dilute vasopressin with a laparoscopic needle, to create a plane between cyst wall and ovarian stroma and strip the cyst capsule with laparoscopic graspers. Type I endometriomas adhere densely to the ovary. Given the presence of fibrosis and adhesions, the cyst is excised in a piecemeal fashion. Care is taken to remove any endometrial implants from the ovary while preserving as much of the ovarian tissue as possible.¹

Type II endometriomas are larger cysts originating from the invasion of endometrial implants or type I endometrioma into functional cysts. The difficulty of capsule excision varies according to the extent of endometrial invasion. Type IIA endometriomas contain less than 10% endometrial tissue within the cyst capsule. Thus, the standard ovarian cystectomy stripping technique is successful in removing more than 90% of the cyst capsule. Special care is taken in stripping the residual small portion that involves the endometrial glands and stroma and adheres densely to the ovary.

The larger proportion of endometrial tissue present in type IIB and IIC endometriomas degrades the plane between the cyst capsule and the ovarian stroma, making excision more difficult. Similar to the type I excision, a piecemeal approach is often necessary. If complete stripping of the cyst capsule would result in extensive loss of healthy ovarian tissue, then electrocautery, plasma energy, or laser ablation can be selectively used to destroy focal areas of endometrial invasion. Complete ablation may be difficult, as the endometrioma wall can be up to 5 mm thick.¹⁹ For these thick-walled endometriomas, we recommend excision (vs ablation), which lowers the risk of endometrioma recurrence.

Related article:
Endometriosis and pain: Expert answers to 6 questions targeting your management options
 

Conclusion

Endometriomas, common adnexal masses in women affected by endometriosis, may exacerbate pelvic pain and impair fertility. Gynecologists should be prepared to excise endometriomas completely and exercise care in preserving as much of the ovarian stroma as possible. We classify endometriomas into 2 types: type I, which develop from invagination of endometrial implants in the ovarian cortex, and type II, which stem from invasion of functional cysts by endometrial implants or type I endometrioma. This distinction guides surgical management. We hope this article and its accompanying video will be helpful in guiding laparoscopic excision of type I and II endometriomas.

Share your thoughts! Send your Letter to the Editor to rbarbieri@frontlinemedcom.com. Please include your name and the city and state in which you practice.

Illustration: Kimberly Martens for OBG Management

Related article:
Endometriosis: Expert answers to 7 crucial questions on diagnosis

Etiology

Endometriomas are extensively described in the literature, and their origin is the subject of several theories. In 1921, Sampson noted luteal membrane and ovarian epithelial tissues within endometriomas and was the first to indicate that endometriomas may result from the invasion of functional cysts by endometrial tissue.^2,4,5 In 1979, Czernobilsky and Morris⁶ found endometrial and oviduct-like epithelium in ovarian endometriosis and concluded that ovarian tissue may be a common histologic precursor. Several other authors subsequently have reported finding different types of tissue within ovarian endometriomas, and not all of these chocolate cysts showed histologic evidence of endometriosis.^4,7,8

Read about the classification of endometriomas

Disease classification

Our classification system identifies 2 types of endometriomas on the basis of their etiologies and characteristics. Type I, which arise from endometrial tissue implanted on the ovarian surface, are also called true endometriomas. Invagination of cortex and subsequent hemorrhage from endometrial tissue result in cyst formation. Endometrial tissue (endometrial stroma and glands) is histologically present in all type I endometriomas.^1,4,9 These endometriomas usually are small (<5 cm in diameter) and have a densely adherent fibrous capsule.⁴ Often, there is no clear plane between cyst wall and ovarian stroma.³

Type II endometriomas arise from functional cysts involved in or invaded by cortical or pelvic side-wall endometrial implants or by type I endometriomas. Type II endometriomas are subclassified by the extent of endometrial implant involvement in the cyst wall. Type IIA endometriomas are hemorrhagic cysts with less than 10% of endometrial tissue within the cyst wall. Similar to the functional cysts from which they originate, type IIA endometriomas have a cyst wall that is separated easily from ovarian tissue during surgery.^4,7,9 Although type II endometriomas tend to be larger than their type I counterparts, in some cases they are identified at an early stage of 2 to 5 cm. Endometriomas larger than 5 cm are almost always type II.⁴

Type IIB and IIC endometriomas have endometrial implants and fibrosis within their cyst walls, with progressively more endometrial invasion in type IIC endometriomas (>50%) than in type IIB (10% to 50%). Consequently, type IIB cysts are relatively easy to dissect from ovarian tissue, except adjacent to an endometriotic area where the cyst densely adheres to the ovarian stroma. In type IIC, endometrial tissue more extensively penetrates the capsule, making dissection of diseased tissue from the ovarian stroma more difficult; in fact, separating type IIC cyst wall from ovarian stroma can be as challenging as excising a type I endometrioma.⁷ In most cases, a type IIC cyst is attached by adhesions and fibrosis to the pelvic side wall or uterus and ruptures during mobilization (TABLE).

Related article:
Imaging the endometrioma and mature cystic teratoma

Presentation and diagnosis

Almost all patients with an endometrioma concurrently have peritoneal endometriosis, which is characterized by dysmenorrhea, dyspareunia, chronic pelvic pain, infertility, and, in some cases, gastrointestinal or genitourinary dysfunction.¹ Pelvic examination may reveal an adnexal mass that is an endometrioma, or an endometrioma may appear on imaging obtained in a pelvic pain or infertility work-up. Given its 73% sensitivity, 94% specificity, safety, and low cost, transvaginal ultrasonography is the preferred imaging modality for endometrioma.³ The characteristic ultrasonographic appearance is that of a round, homogeneous, fluid-filled mass with low-level echoes.¹ Magnetic resonance imaging is appropriate when a more sensitive imaging modality is indicated, as for a patient with risk factors for malignancy.^3,10–12

Read about the surgical management of endometriomas

Surgical management

Indications for surgical excision of endometriomas include pelvic pain, infertility, and prevention and diagnosis of malignancy. Endometriomas may be excised prior to use of assisted reproductive technology.^13–15 Medical therapy, such as oral contraceptives, can be used to reduce the size of endometriomas but does not improve fertility.³ Certain ovarian cancers are more common in women with endometriosis, and ovarian tumors are thought to develop in about 1% of ovarian endometriosis cases.^1,12 Therefore, endometrioma excision may reduce the risk of malignancy. As with other ovarian cysts, large endometriomas may be excised to reduce the risks of rupture and torsion.

Don't miss the video that accompanies this article!

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To watch the authors perform laparoscopic excision of type I and type II endometriomas, click here

 

Approach

Laparoscopy is the preferred approach for endometrioma excision. Controversy exists regarding the ideal procedure: complete excision (with stripping of the cyst capsule) or drainage and ablation of the cyst wall. Compared with drainage and ablation, excision reduces recurrence of endometriomas; relieves dysmenorrhea, dyspareunia, pelvic pain, and other symptoms; and improves fertility.^13,16 The recurrence rate may be as low as 5.8% with complete excision but is 90% with simple transvaginal aspiration.^17,18 If not performed properly, however, cyst capsule stripping may damage nearby ovarian stroma and decrease the ovarian reserve.¹⁴ Some authors have advocated combining excision and ablation—performing cystectomy until there is no longer a clear plane between capsule and ovarian stroma and then ablating any remaining endometrial tissue.⁸

With type I and IIC endometriomas, we have seen the endometrial cyst wall infiltrating the ovarian stroma so deeply there is not always a definable plane. By contrast, type IIA and IIB endometriomas typically have a plane between the cyst wall and the ovarian cortex. In type II endometriomas, endometrial implants on the ovarian cortex infiltrate the plane of the cyst wall such that the juxtaposing lipomatous follicular cyst detaches with minimal intraoperative traction. Portions of type II endometriomas containing fibrosis and adhesions may become more difficult to peel off the cyst wall. For most endometriomas, at least 1 spot is difficult to peel off the ovary, and extra care must be taken at the hilum of ovary to avoid excising healthy ovarian cortex.^4,5,7,8

Our surgical approach accounts for the described variations in type I and II endometriomas. Endometrial contents often spill as the endometrioma is dissected off neighboring structures. When possible, endometriomas should be aspirated and irrigated prior to cystectomy to avoid seeding the pelvis and abdomen with spilled endometriotic contents. We use hydrodissection, the injection of dilute vasopressin with a laparoscopic needle, to create a plane between cyst wall and ovarian stroma and strip the cyst capsule with laparoscopic graspers. Type I endometriomas adhere densely to the ovary. Given the presence of fibrosis and adhesions, the cyst is excised in a piecemeal fashion. Care is taken to remove any endometrial implants from the ovary while preserving as much of the ovarian tissue as possible.¹

Type II endometriomas are larger cysts originating from the invasion of endometrial implants or type I endometrioma into functional cysts. The difficulty of capsule excision varies according to the extent of endometrial invasion. Type IIA endometriomas contain less than 10% endometrial tissue within the cyst capsule. Thus, the standard ovarian cystectomy stripping technique is successful in removing more than 90% of the cyst capsule. Special care is taken in stripping the residual small portion that involves the endometrial glands and stroma and adheres densely to the ovary.

The larger proportion of endometrial tissue present in type IIB and IIC endometriomas degrades the plane between the cyst capsule and the ovarian stroma, making excision more difficult. Similar to the type I excision, a piecemeal approach is often necessary. If complete stripping of the cyst capsule would result in extensive loss of healthy ovarian tissue, then electrocautery, plasma energy, or laser ablation can be selectively used to destroy focal areas of endometrial invasion. Complete ablation may be difficult, as the endometrioma wall can be up to 5 mm thick.¹⁹ For these thick-walled endometriomas, we recommend excision (vs ablation), which lowers the risk of endometrioma recurrence.

Related article:
Endometriosis and pain: Expert answers to 6 questions targeting your management options
 

Conclusion

Endometriomas, common adnexal masses in women affected by endometriosis, may exacerbate pelvic pain and impair fertility. Gynecologists should be prepared to excise endometriomas completely and exercise care in preserving as much of the ovarian stroma as possible. We classify endometriomas into 2 types: type I, which develop from invagination of endometrial implants in the ovarian cortex, and type II, which stem from invasion of functional cysts by endometrial implants or type I endometrioma. This distinction guides surgical management. We hope this article and its accompanying video will be helpful in guiding laparoscopic excision of type I and II endometriomas.

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Bacterial vaginosis (BV) is caused by a complex change in vaginal bacterial flora, with a reduction in lactobacilli (which help maintain an acidic environment) and an increase in anaerobic gram-negative organisms including Gardnerella vaginalis species and Bacteroides, Prevotella, and Mobiluncus genera. Infection with G vaginalis is thought to trigger a cascade of changes in vaginal flora that leads to BV.¹

Photo: CDC/ M. Rein

BV is present in 30% to 50% of sexually active women, and of these women 50% to 75% have an abnormal vaginal discharge, which is gray, thin, and homogeneous and may have a fishy odor.² In addition to causing an abnormal vaginal discharge, BV is a cause of postpartum fever, posthysterectomy vaginal cuff cellulitis, and postabortion infection, and it increases the risk of acquiring HIV, herpes simplex type 2, gonorrhea, chlamydia, and trichomoniasis infection.³

When using microscopy and the Amsel criteria, the diagnosis of BV is made when at least 3 of the following 4 criteria are present:  

1. homogeneous, thin, gray discharge  
2. vaginal pH >4.5  
3. positive whiff-amine test when applying a drop of 10% KOH to a sample of the vaginal discharge  
4. clue cells detected with microscopy on a saline wet mount.  

If microscopy is not available, the Affirm VPIII test (BD Diagnostic Systems, Franklin Lakes, New Jersey) for DNA sequences of G vaginalis has high sensitivity and specificity.⁴ The OSOM BVBlue test (Sekisui Diagnostics, Lexington, Massachusetts), a Clinical Laboratory Improvement Amendments-waived point of service test, measures vaginal sialidase, which is produced by Gardnerella and other pathogens associated with BV.⁵ BV may be detected in routine cervical cytology testing and, if the patient is symptomatic, treatment is recommended.

Initial treatment of BV. The Centers for Disease Control and Prevention (CDC) has recommended 3 treatment regimens for BV and 4 alternative treatment options (TABLE).⁶ In addition to antimicrobial treatment, the CDC recommends that women with BV use condoms with sexual intercourse. The CDC also advises that clinicians should con-sider testing women with BV for HIV and other sexually transmitted infections.