Multiple Sclerosis Centers of Excellence
Pregnancy in Multiple Sclerosis
Jacqueline Bernard, MD, FAAN
MS affects women nearly three times as often as men, and often presents during childbearing years, making pregnancy issues very important for people living with MS. Questions around pregnancy and MS are a common part of patient-physician conversations.
Impact of Pregnancy on MS
Since MS is usually diagnosed in individuals between the ages of 20-40, the impact of pregnancy on MS is an important clinical concern. Fortunately, MS is typically least likely to relapse during pregnancy. Several reasons probably account for this, including immunological changes thought to protect the developing fetus. Reduced disease activity during pregnancy also occurs with some other autoimmune diseases, such as psoriasis and rheumatoid arthritis. The hormonal changes accompanying pregnancy, such as increasing levels of estradiol and estriol, peak in the third trimester, and these peaks correlate with decreased risk of MS activity during this time by as much as 70%. So, although these changes likely are meant to protect the developing baby, these changes are also protective for the mother.
Another consideration for women with MS planning pregnancy is concern about fatigue, a very common symptom for any expectant mother. Fatigue is also one of the most common symptoms of MS. In non-pregnant women with MS, numerous medications can be used to manage fatigue, but these are not considered safe during pregnancy. To combat fatigue, it is important to allow for adequate rest, and pay close attention to overall health during pregnancy. Watching for urinary tract infections as well as preventing pregnancy-associated anemia by taking prenatal vitamins with iron supplementation are some practical ways to reduce pregnancy-associated fatigue which may compound MS fatigue.
Over the longer-term, people with MS may wonder about the impact of the number of pregnancies on their MS progression. Studies thus far do not show worsening of an individual’s overall MS course based on the number of pregnancies. Additionally, one study showed that having one or more pregnancies was associated with a lower risk of developing MS than having no pregnancies at all. While this is only one study, this is encouraging for women with MS who are considering having a child, but of course pregnancy is not a sustainable treatment for MS and does not substitute for disease modifying treatments (DMTs).
For those who do experience MS relapse during pregnancy, intravenous steroids (methylprednisolone) or intravenous immunoglobulin (IVIG) can be used. Coordination of care between the treating neurologist and OB/GYN is important should this occur.
Impact of MS on Pregnancy
Ten to 15 percent of people in the US have impaired fertility and the number is similar for people with MS. Some people with more progressive MS may experience sexual dysfunction which could lead to impaired fertility, and this may require more specific management with counseling and possibly physical therapy and/or medications. People with MS who do experience infertility may need to use assisted reproductive technology (ART), and these approaches can be associated with a slight, temporary increased risk of MS relapse.
People with MS do not have an increase in pregnancy complications due to MS, such as premature delivery. In general, there is no evidence of an association between maternal MS and adverse effects on fetal development.
Since unplanned pregnancies do occur, it is important for people with MS to know that there is no evidence for any negative impact from use of contraceptives on MS disease course. For many, use of long-acting reversible contraceptives (LARC), such as IUDs, are particularly helpful, since the risks of non-compliance are reduced, and this results in fewer unintended pregnancies. In general, any form of contraception is safe for people with MS. This is an important topic to be discussed with either a primary care provider or OB/Gyn.
Impact of Disease-Modifying Treatments on Pregnancy
Currently, there are over twenty Federal Drug Administration (FDA) approved DMTs for MS in the US. These range from moderately to highly effective, each with unique potential adverse effects with regard to pregnancy and variable recommendations for stopping prior to attempts at conception due to mechanisms of action. Given the risk of unplanned pregnancy in the general population, discussions regarding choice of a DMT must be done in parallel with family planning discussions with both women and men with MS.
Pregnancy planning discussions should ideally start at least 6 months before attempts at conception so neurologic assessment of stability and specific recommendations for continuing, changing, or stopping DMTs can be made based on known risk guidelines. Drug-specific information relating to safety during pregnancy and information about pregnancy exposure registries are included in package inserts. This information suggests that GA and interferon-beta are the safest DMTs for use during pregnancy but, given differences in MS disease activity and risk for rebound disease activity with stopping certain DMTs, recommendations for each individual needs to be made based on considerations of the person-specific risk vs benefit both to the mother and the developing fetus.
Many recommend ensuring adequate serum vitamin D levels in people with MS, particularly during pregnancy, as this is associated with lower risk of MS relapses in mothers with MS and lower risk of developing MS in their offspring.
Breast-Feeding and Post-Partum Considerations
Typically, the benefits of pregnancy with regard to the lower MS relapse rate rapidly diminishes postpartum, with risk of MS relapse peaking at around 3-6 months after delivery. There is not sufficient consistent evidence currently that supports not resuming DMT in that time frame in women with MS, particularly those with very active disease. Since DMTs vary in safety during lactation, as well as how quickly a therapeutic benefit occurs after resuming these medications, people with MS and physicians should be prepared early by discussing before delivery how and when to restart medications.
Often, an MRI will help guide these discussions because MRI can provide information about how active MS disease is post-partum. Gadolinium use during pregnancy is controversial but if given during lactation very little would be expected to be absorbed by the infant. There is no need to interrupt breastfeeding after gadolinium administration. Timing of post-partum MRI should be based on clinical status of the mother, as well as breast-feeding and family planning goals, but would be urgently indicated if an acute relapse occurs.
