The pandemic has created a hostile environment for pregnant people and their babies.
Stress levels among expectant mothers have soared. Pregnant women with COVID are 5 times as likely as uninfected pregnant people to require intensive care and 22 times as likely to die. Infected moms are four times as likely to have a stillborn child.
Yet some of the pandemic’s greatest threats to infants’ health may not be apparent for years or even decades.
That’s because babies of COVID-infected moms are 60% more likely to be born very prematurely, which increases the danger of infant mortality and long-term disabilities such as cerebral palsy, asthma, and hearing loss, as well as a child’s risk of adult disease, including depression, anxiety, heart disease, and kidney disease.
Studies have linked fever and infection during pregnancy to developmental and psychiatric conditions such as autism, depression, and schizophrenia.
“Some of these conditions do not show up until middle childhood or early adult life, but they have their origins in fetal life,” said Evdokia Anagnostou, MD, a child neurologist at Holland Bloorview Kids Rehabilitation Hospital and a pediatrics professor at the University of Toronto.
For fetuses exposed to COVID, the greatest danger is usually not the coronavirus itself, but the mother’s immune system.
Both severe COVID infections and the strain of the pandemic can expose fetuses to harmful inflammation, which can occur when a mother’s immune system is fighting a virus or when stress hormones send nonstop alarm signals.
Prenatal inflammation “changes the way the brain develops and, depending on the timing of the infection, it can change the way the heart or kidneys develop,” Dr. Anagnostou said.
Although health officials have strongly recommended COVID vaccines for pregnant people, only 35% are fully vaccinated.
At least 150,000 pregnant women have been diagnosed with COVID; more than 25,000 of them have been hospitalized, and 249 have died, according to the Centers for Disease Control and Prevention.
Although most babies will be fine, even a small increase in the percentage of children with special medical or educational needs could have a large effect on the population, given the huge number of COVID infections, Dr. Anagnostou said.
“If someone has a baby who is doing well, that is what they should focus on,” Dr. Anagnostou said. “But from a public health point of view, we need to follow women who experienced severe COVID and their babies to understand the impact.”
Learning from history
Previous crises have shown that the challenges fetuses face in the womb – such as maternal infections, hunger, stress, and hormone-disrupting chemicals – can leave a lasting imprint on their health, as well as that of their children and grandchildren, said Frederick Kaskel, MD, director of pediatric nephrology at the Children’s Hospital at Montefiore, New York.
People whose mothers were pregnant during surges in the 1918 influenza pandemic, for example, had poorer health throughout their lives, compared with Americans born at other times, said John McCarthy, who is a medical student at Albert Einstein College of Medicine, New York, and cowrote a recent review in JAMA Pediatrics with Dr. Kaskel.
Researchers don’t know exactly which moms were infected with pandemic flu, Mr. McCarthy said. But women who were pregnant during major surges – when infection was widespread – had children with higher rates of heart disease or diabetes. These children were also less successful in school, less economically productive, and more likely to live with a disability.
Because organ systems develop during different periods of pregnancy, fetuses exposed during the first trimester may face different risks than those exposed toward the end of pregnancy, Mr. McCarthy said. For example, people born in the fall of 1918 were 50% more likely than others to develop kidney disease; that may reflect an exposure to the pandemic in the third trimester, while the kidneys were still developing.
Nearly 2 years into the COVID pandemic, researchers have begun to publish preliminary observations of infants exposed to COVID infections and stress before birth.
Although Dr. Anagnostou noted that it’s too early to reach definitive conclusions, “there is evidence that babies born to moms with severe COVID infections have changes to their immune system,” she said. “It’s enough to make us worry a little bit.”