MS is more prevalent in women of childbearing age than in any other group. When young women receive a diagnosis of MS, they frequently have questions about the effects of the disease on childbearing—and vice versa. Studies undertaken over the past several decades allow health professionals to provide answers to some of these questions.
Effects of MS on Fertility
There is no evidence that MS impairs fertility or leads to an increased number of spontaneous abortions, stillbirths or congenital malformations. Several studies of large numbers of women have repeatedly demonstrated that pregnancy, labor, delivery and the incidence of fetal complications are no different in women who have MS than in control groups without the disease.
Effects of Pregnancy on MS
Before 1950, most women with MS were counseled to avoid pregnancy because of the belief that it might make their MS worse. Over the past 40 years, many studies have been done in hundreds of women with MS, and they have almost all reached the opposite conclusion: that pregnancy reduces the number of MS exacerbations, especially in the second and third trimesters.
Effects in the Postpartum Period
Exacerbation rates tend to rise in the first three to six months postpartum, and the risk of a relapse in the postpartum period is estimated to be 20-40%. These relapses do not appear to contribute to increased long-term disability. In the studies with long-term follow-up of women with MS who had children, no increased disability as a result of pregnancy was found.
Pregnancy is known to be associated with an increase in a number of circulating proteins and other factors that are natural immunosuppressants. Additionally, levels of natural corticosteroids are higher in pregnant than nonpregnant women. These may be some of the reasons why women with MS tend to do well during pregnancy.
Medical Management During Pregnancy, Delivery, and Postpartum
None of the disease-modifying medications—Aubagio®, Avonex®, Betaseron®, Copaxone®, Extavia®, GilenyaTM, Novantrone®, Rebif®, TecfideraTM or Tysabri®—are approved for use during pregnancy. Women who are taking any of these medications should discuss their plan to become pregnant with their prescribing physician.
The disease-modifying drugs are not recommended during breastfeeding because it is not known if they are excreted in breast milk. A woman should also review any other medications she is taking with her neurologist and obstetrician in order to identify those that are safe during pregnancy and breastfeeding.
Studies have indicated no increased risk of relapse of MS associated with breastfeeding. Women with MS usually need no special gynecologic care during pregnancy. Labor and delivery are usually the same as in other women and no special management is needed. All forms of anesthesia seem to be well tolerated by women in labor.
Use of Steroid Medications
Women who use steroids for acute MS exacerbations may continue to use them during pregnancy. The use of prednisone in a woman who is breastfeeding should be carefully monitored.
Special Concerns for the Pregnant Patient With MS
Women who have gait difficulties may find these get worse during late pregnancy as they become heavier and their center of gravity shifts. Increased use of assistive devices to walk or use of a wheelchair may be advisable at these times. Bladder and bowel problems, which occur in all pregnant women, may be aggravated in women with MS who have pre-existing urinary or bowel dysfunction. MS patients may also be more subject to fatigue.
In general, pregnancy does not appear to affect the long-term clinical course of MS. Women who have MS and wish to have a family can usually do so successfully with the assistance of their neurologist and obstetrician.