Moms with MS at no more risk of pregnancy complications than moms without MS

Feb 03, 2021

Women with multiple sclerosis may not be at a higher risk of pregnancy complications like gestational diabetes, emergency cesarean section or stillbirth than women who do not have the disease, according to a study in the February 3, 2021, online issue of Neurology® Clinical Practice, an official journal of the American Academy of Neurology. However, the study did find that babies born to mothers with multiple sclerosis had a higher chance of being delivered by elective cesarean section (c-section) or induced delivery, and being small for their age compared to babies of women who did not have the disease.

"Women with multiple sclerosis may be understandably concerned about the risks of pregnancy," said study author Melinda Magyari MD PhD, of the University of Copenhagen in Denmark. "While previous research has shown there is no higher risk of birth defects for babies born to women with multiple sclerosis, there are still a lot of unknowns around pregnancy and multiple sclerosis. We wanted to find out if women with multiple sclerosis are at risk for a variety of pregnancy complications. We found overall their pregnancies were just as healthy as those of the moms without multiple sclerosis."

The study involved 2,930 pregnant women with multiple sclerosis who were compared to 56,958 pregnant women without multiple sclerosis. All women gave birth between 1997 and 2016.

Researchers found no difference in risk of several pregnancy complications between women with multiple sclerosis and women without it. No differences were found in risk of preeclampsia, gestational diabetes, placenta complications, emergency c-section, instrumental delivery, stillbirth, preterm birth, congenital malformations or low Apgar score. Apgar score is a test of a newborn's health, including measures like heart rate, reflexes and muscle tone immediately after birth.

Researchers did find that 401 of the 2,930 women with multiple sclerosis, or 14%, had an elective c-section, compared to 4,402 of the 56, 958 women without multiple sclerosis, or 8%, who had an elective c-section. After adjusting for other factors that could increase the likelihood of having an elective c-section, such as prior c-section and mother's age, women with multiple sclerosis were 89% more likely to have an elective c-section.

Researchers also found women with multiple sclerosis were 15% more likely to have an induced delivery than women without the disease.

Also, women with multiple sclerosis were found to be 29% more likely to have babies that were born small for their gestational age compared to women without multiple sclerosis. Overall, 3.4% of women with multiple sclerosis had babies small for their gestational age, compared to 2.8% of women without multiple sclerosis.

"We think the reason more women with multiple sclerosis have babies by elective c-section or induced delivery may have to do with multiple sclerosis-related symptoms such as muscle weakness, spasticity or fatigue that might affect the birth," Magyari said. "Any of these could make a mom more tired and lead to delivery complications that could prompt the clinician and woman to take extra precautions."

Researchers also found that mothers with multiple sclerosis were 13% less likely to give birth to babies with signs of being deprived of oxygen, or asphyxia. Magyari said the higher prevalence of elective c-sections among women with multiple sclerosis most likely explains the corresponding lower odds of asphyxia.

A limitation of the study is the lack of data on the mothers' smoking, which could cause babies to be born small for their gestational age.

Source: News Release
American Academy of Neurology
February 3, 2021