Life with MS

Pregnancy and Multiple Sclerosis

By Michael J. Bradshaw and Dr. Maria Houtchens
Although the majority of women with MS are diagnosed during their reproductive years, most of our patients are successful in achieving a happy, healthy pregnancy and are able to enjoy parenthood to the fullest extent. It is important to familiarize yourself with the effects of pregnancy on the course of MS, the effects of MS on the course of pregnancy, and the evidence regarding the use of disease-modifying medications in pregnancy. We ask our patients to inform us when they are considering pregnancy and dedicate an appointment to establishing an individualized pregnancy and MS treatment plan. This plan is different for every person and should take into consideration your preferences, age, the severity/aggressiveness of your MS, which DMT you take, and a number of other factors.
Getting pregnant
Persons with MS are considered to have normal fertility and most women with MS are able to conceive “the old-fashioned” way. However, the use of reproductive technology does appear to be slightly higher. Although large studies have not investigated the effects of assisted reproductive technologies on MS, smaller studies suggest an increased risk of relapse with the use of gonadotropin-releasing hormone agonists. If you are considering assistive technology, it is important to review this information with your fertility specialist and neurologist.
Effects of pregnancy on MS
The Pregnancy in MS (PRIMS) study was the first large prospective study intended to understand the effect of pregnancy on the risk of MS relapses and progression. PRIMS found that a woman’s risk of relapse decreased from her baseline during pregnancy with the fewest relapses in the third trimester (Figure 1). However, there was an increased risk of relapse in the first three months postpartum to nearly twice the baseline relapse rate. Pregnancy did not appear to affect the risk of progression. These results were replicated in several additional studies, although the relapse rates and magnitude of the postpartum rebound were lower than those seen in PRIMS. The protective effects of pregnancy on MS are likely consequent to hormone-mediated changes in the immune system, which becomes “less active” in pregnancy, and relatively “more active” temporarily right after delivery. Some evidence suggests that pregnancy may have favorable long-term effects on MS, such as slowing progression of disability.


Disease-modifying therapy and pregnancy
There are more than a dozen different DMTs for the treatment of MS and each has different implications for pregnancy. According to the FDA, DMTs should not be taken while attempting to conceive, pregnant, or breastfeeding. For a patient with stable and well-controlled MS, we typically recommend discontinuing DMT and waiting for the medication to be eliminated from the body prior to attempting conception (Table 1). For women with more active MS, we may consider periodic treatment with steroids to reduce the risk of relapse in the pre-conception stage. Some clinical circumstances may warrant ongoing treatment while pregnant, but this decision should be made only after a careful exploration of the risks for harm to the fetus and mother with or without DMT during pregnancy.


Relapses during and shortly after pregnancy
The risk of relapse is decreased in pregnancy, but not absent. Urinary tract infections are more common in pregnancy and can produce symptoms similar to a relapse, known as a pseudorelapse. Gadolinium contrast should be avoided during pregnancy, but MRI can be performed in pregnancy, if necessary. In the first trimester, steroids may slightly increase the risk of cleft palate (although recent studies have not found this association). In the second and third trimesters, steroids may increase the risk of preterm labor and lower birth weight, but are appear to be safe for the fetus. It is important to balance the risks and benefits of treating a relapse, and your neurologist should help you chose the safest approach for you and your baby.
Three to six months postpartum is a high relapse risk period. You will be tired from delivery, pregnancy, and the demands of having a new baby in the home. Here again, an individualized approach is essential, and you and your neurologist should consider your desire to breastfeed as well as your risk of a relapse when developing a plan. Breastfeeding is best for your baby and some women may be effectively protected from relapse by exclusive breastfeeding, while others may benefit from early treatment initiation although the data are not clear on this yet. All women should be monitored very closely in the postpartum period. Some neurologists, to try to decrease the risk of post-partum flares, have used steroids and/or Intravenous Immunoglobulin.
Delivery and breast feeding
Apart from any specific mobility or balance issues, women with MS do not require any particular changes in the usual individualized management of pregnancy. In general, pregnant women with MS are at slightly higher risk of high blood pressure during pregnancy and the rates of forceps and/or vacuum assisted delivery and cesarean section are also slightly higher. Epidural and spinal anesthesia appear to be safe for women with MS, and there is no evidence suggesting an increase in the risk of relapse. Children of women with MS may have slightly decreased birth weight but are otherwise healthy. We suggest pumping and discarding breast milk for a few hours after treatment with high-dose steroids, such as those used for the treatment of a relapse. Less than 0.1 percent of gadolinium enters breast milk, however, we recommend that patients pump and discard for 24 hours after an MRI, substituting formula during that time.
  • Women with MS can safely undergo pregnancy and deliver babies
  • Family planning is important and should be discussed with MS specialist regularly so that appropriate and safe treatment plan can be put in place
  • There is an increased risk of relapses in the postpartum period. The decision to breastfeed or to return to pre-pregnancy MS therapy should be individualized.