Pregnancy may increase risk of mental illness in people with multiple sclerosis

Pregnant people with multiple sclerosis have a higher chance of experiencing mental illness both during their pregnancy and in the first years after they give birth than those without multiple sclerosis, according to a study published in the January 22, 2025, online issue of Neurology^®, the medical journal of the American Academy of Neurology.

“Previous studies have shown that women with multiple sclerosis are more likely to have depression, anxiety disorders, and bipolar disorder compared to women without multiple sclerosis,” said study author Ruth Ann Marrie, MD, PhD, of Dalhousie University in Halifax, Canada, and member of the American Academy of Neurology. “Mental health struggles can affect both parents and kids, making it important to understand how mental health challenges around pregnancy affect people with multiple sclerosis.”

The study involved 894,852 pregnant people. Of the group, 1,745 people had multiple sclerosis, 5,954 people had epilepsy, 4,924 people had irritable bowel disease, and 13,002 people had diabetes. They were matched to 869,227 pregnant people who did not have multiple sclerosis or any of the other conditions.

Researchers looked at health records for people who gave birth during a 15-year span. They looked at records from two years before conception to three years after the participants gave birth.

Researchers then looked at how many participants had newly diagnosed or existing mental illness during pregnancy, and in the first, second and third years after giving birth. Mental illnesses included anxiety, depression, bipolar disorder, psychosis, suicide attempts and substance abuse.

They found that mental illness affected 42% of people with multiple sclerosis during pregnancy and increased to 50% in the first year after giving birth, compared to 30% of people without multiple sclerosis during pregnancy and 38% in the first year after birth.

A total of 8% of people with multiple sclerosis had new mental illness diagnoses during pregnancy and 14% had new diagnoses in the first year after birth, compared to 7% and 11% of those without multiple sclerosis.

After adjusting for factors such as age at conception and income in the area of residence, researchers found that pregnant people with multiple sclerosis had a 26% increased risk of mental illness during pregnancy and a 33% increased risk after giving birth when compared to pregnant people without multiple sclerosis.

In addition, researchers found that people with multiple sclerosis had an increased risk of all specific mental illnesses except suicide attempts. They also found that substance use increased in people with multiple sclerosis from 0.54% during pregnancy to 6% after giving birth.

“These findings emphasize the need for preventive and early treatment of mental illness,” said Marrie. “Future studies should look at how multiple sclerosis affects mental health in mothers during and after pregnancy and if it’s worse in different stages of multiple sclerosis. Doctors should know about these risks, make sure to check mental health, and provide treatment if needed.”

A limitation of the study was that researchers were unable to look at how severe participants’ multiple sclerosis was, what treatments people were using or their health habits.

The study was supported by MS Canada and ICES, formerly the Institute for Clinical Evaluative Sciences.

Source: News Release
American Academy of Neurology
January 22, 2025