New evidence provides estimates of the pregnancy rates for American women with multiple sclerosis (MS), their complication rates, and the rates of relapse and disease-modifying drug treatment during different phases before and after pregnancy.
The two new studies, conducted by Maria K. Houtchens, MD, of Brigham and Women’s Hospital and Harvard Medical School, Boston, and her colleagues involved retrospective mining of U.S. commercial health plan data in the IQVIA Real-World Data Adjudicated Claims–U.S. database between Jan. 1, 2006, and June 30, 2015.
The mean age of pregnant women in the nine annual cohorts during that period was just over 32 years for those with MS and just over 29 years for those without. The percentage of women without MS who had a pregnancy-related claim in the database declined from 8.83% in 2006 to 7.75% in 2014 after adjusting for age, region, payer, and Charlson Comorbidity Index score, whereas the percentage increased in women with MS during the same period, from 7.91% to 9.47%. The investigators matched 2,115 women with MS and 2,115 without MS who had live births for a variety of variables and found that women with MS had higher rates of premature labor (31.4% vs. 27.4%; P = .005), infection in pregnancy (13.3% vs. 10.9%; P = .016), maternal cardiovascular disease (3.0% vs. 1.9%; P = .028), anemia or acquired coagulation disorder (2.5% vs. 1.3%; P = .007), neurologic complications in pregnancy (1.6% vs. 0.6%; P = .005), and sexually transmitted diseases in pregnancy (0.4% vs. 0%; P = .045). During labor and delivery, women with MS who had a live birth more often had a claim for acquired damage to the fetus (27.8% vs. 23.5%; P = .002) and congenital fetal malformations (13.2% vs. 10.3%; P = .004) than did women without MS.
In the second study, Dr. Houtchens and two coauthors from the first study of the database reported on a set of 2,158 women who had a live birth during the study period and had 1 year of continuous insurance eligibility before and after pregnancy. The odds for having an MS relapse declined during pregnancy (odds ratio, 0.623; 95% confidence interval, 0.521-0.744), rose during the 6-week postpartum puerperium (OR, 1.710; 95% CI, 1.358-2.152), and leveled off during the last three postpartum quarters to remain at a higher level than before pregnancy (OR, 1.216; 95% CI, 1.052-1.406). Disease-modifying drug treatment followed the same pattern with 20% using it before pregnancy, dropping to about 2% in the second trimester, and peaking in about a quarter of all patients 9-12 months post partum.
SOURCES: Houtchens MK et al. Neurology. 2018 Sep 28. doi: 10.1212/WNL.0000000000006382; Houtchens MK et al. Neurology. 2018 Sep 28. doi: 10.1212/WNL.0000000000006384.