Women with multiple sclerosis (MS) who receive high-efficacy disease-modifying therapies (DMTs) before conception have a greater risk of relapses and disability progression during pregnancy than those given moderate-efficacy or no DMTs, according to a systematic review of studies.
Exclusive breastfeeding for at least two to four months, however, was associated with a significantly lower risk of relapses after delivery.
The findings suggest that a decision regarding DMT use “before, during, and after pregnancy for treating MS remains difficult,” the researchers wrote, adding that “treatment decisions need to be taken by the patient and healthcare professional after careful consideration of all of the potential benefits and risks.”
The study, “A systematic review of relapse rates during pregnancy and postpartum in patients with relapsing multiple sclerosis,” was published in the journal Therapeutic Advances in Neurological Disorders.
MS is the most common neurologic condition in women of reproductive age, but women wanting to conceive are usually advised to discontinue their DMTs, despite evidence demonstrating that stopping DMTs increases the risk of relapse during and after pregnancy.
Recently, the European Medicines Agency allowed the use of some DMTs — namely interferon betas — during pregnancy and breastfeeding, after extensive research demonstrated that these do not raise the risk of adverse pregnancy outcomes. But whether these remain safe beyond the third trimester remains unknown.
In addition to decisions about stopping or not stopping their DMTs, women are faced with several other decisions, such as when to resume DMTs after delivery and whether to forgo breastfeeding. But the “best strategy to reduce the rate of relapse during and after pregnancy remains up for deliberation,” the researchers wrote.