Breastfeeding with MS: Monoclonal Antibodies May Not Impact Child Development

The use of multiple sclerosis (MS) therapies during breastfeeding is a complex issue that requires careful consideration of the benefits and risks to both the mother and the infant, especially since many disease-modifying therapies (DMTs) have not been extensively studied nor approved in breastfeeding women.

But since MS is often diagnosed during childbearing years and there’s an increased risk of relapse after childbirth, some patients may want or need to begin taking these therapies again.

That’s why a recent study presented at the 76^th American Academy of Neurology (AAN) Annual Meeting sought to determine whether DMTs known as monoclonal antibodies negatively affect a child’s development when taken while breastfeeding. This preliminary study focused on the following four monoclonal antibody medications: natalizumab, ocrelizumab, rituximab, and ofatumumab.

Using the German MS and Pregnancy Registry, researchers identified 183 infants born to breastfeeding mothers who were taking one of the four monoclonal antibodies previously mentioned. Those infants were then compared to another 183 infants who were born to mothers with MS who took a monoclonal antibody before or during their pregnancy but not while breastfeeding.

In the former cohort, 125 infants were exposed to natalizumab, 34 to ocrelizumab, 11 to rituximab, and 10 to ofatumumab. The range for these infants’ first exposure to these monoclonal antibodies was the day of their birth to their first 9 months, and on average, these infants were breastfed for 5.5 months.

To assess any potential impacts of monoclonal antibodies on an infant’s development, the researchers studied the number of hospital stays, antibiotic use, developmental delays like problems with social and fine motor skills and delayed speech development, and the infants’ weight at follow-up visits throughout the first 3 years of their life.

Based on their examination, no health or development differences during the first 3 years of life were found when comparing infants who were exposed to monoclonal antibodies versus those who were not.

However, it’s important to note that the majority of infants were not followed for the full study duration; only a third of patients were followed for the first 3 years of their life. Therefore, the researchers concluded that the results for the first 2 years are more meaningful.

But despite this limitation, these findings could open the door for more studies being conducted that focus on the safety of monoclonal antibodies and other DMTs for breastfeeding mothers and their infants.

Reference:

Good news-MS drugs taken while breastfeeding may not affect child development. AAN Publications. Accessed March 27, 2024. https://www.aan.com/PressRoom/Home/PressRelease/5153.