Multiple sclerosis is often diagnosed in young adults during their prime reproductive years. So pregnancy and parenthood are common concerns for many people living with multiple sclerosis. Contrary to what physicians thought decades ago, pregnancy does not make multiple sclerosis worse. With so many treatment options, family planning is an important part of disease management for men and women with MS.
Fertility and maternal MS
Multiple sclerosis has no significant impact on the ability to conceive, on the development of the fetus, or the mother’s ability to carry to term. MS doesn’t seem to increase the risk of spontaneous abortions, stillbirth, cesarean delivery, premature birth, or birth defects. However, a recent study suggests that MS patients may have decreased ovarian reserve, a term used to describe the ovary’s capacity to produce egg cells that can be fertilized.
A recent study of men with MS who fathered children found that paternal MS had no impact on birth weight or premature birth. Researchers also determined that factors such as disease duration and disability did not impact birth outcomes. Data regarding semen quality is limited, but one study reports lower total sperm counts, reduced sperm motility, and increased percentage of abnormally formed sperm in men with MS.
MS is a complex disease, for which the exact cause or causes have yet to be determined. It is believed that a combination of environmental and genetic factors are involved.
People with MS may be concerned about the risk of their children developing it. Although researchers have identified a number of genetic variants associated with MS, an estimated 80 percent of people with MS have no relative with the disease. Having a first-degree relative with MS increases disease risk from 0.13 to 2-2.5 percent, with slightly higher risk associated with siblings rather than parents. The risk of MS increases to at least 30 percent in identical twins or when both parents have MS.
Vitamin D deficiency increases the risk of MS and women planning to become pregnant should have their vitamin D serum levels checked and treated prior to pregnancy. As with healthy women, women with MS should take prenatal vitamins and folic acid, avoid alcohol and smoking, eat a healthy diet, and get quality sleep.
Pregnancy and MS prognosis
Studies suggest that pregnancy may provide a protective benefit against the development of clinically isolated syndrome (CIS) or MS. However, one small study of radiologically isolated syndrome (RIS) found that pregnancy was associated with increased risk of subsequent clinical attack during the postpartum period. Patients with RIS who become pregnant should be followed more closely.
Most of what we know about pregnancy and MS is related to women with relapsing MS. Data related to pregnancy in women with progressive MS patients is very limited. It would be helpful if ALL women with MS who become pregnant would join a pregnancy registry, such as MothertoBaby.org, so that outcomes could be tracked.
People living with MS may be concerned that it will have a negative economic and psychosocial impact on raising children, and they may choose not to become pregnant. In a survey of almost 6,000 MS patients diagnosed during their reproductive years, 79 percent did not become pregnant after diagnosis, and for a third of them, the choice involved MS-related issues. Patients were concerned that MS would interfere with parenting, and they didn’t want to burden their partners or pass MS on to their children.
Contraception, DMT use, and washout periods
Any woman with MS who is capable of becoming pregnant should talk to her doctor about contraception before starting disease-modifying therapy. Doctors may recommend delaying DMT use in newly-diagnosed women who want to start a family in the near future. However, a large study from the MSBase global registry reported that prior DMT use, any time in the two years before pregnancy, resulted in a 45 percent decreased risk for postpartum relapse. Patients with aggressive MS may want to control disease activity first with a DMT before thinking about pregnancy.
Some DMTs require a washout period to allow the medication to fully clear the body. Doing so limits risk to the fetus. To reduce the risk of relapse and rebound disease activity, researchers suggest that the DMT washout period should be as short as possible. One consensus group proposed monthly pulsed corticosteroids until pregnancy is achieved in very active MS women, or those with a history of delayed conception.
Studies have shown that women with MS who undergo in vitro fertilization and do not conceive may be at increased risk for clinical and MRI disease activity in the three months post procedure. Although data is limited, this appears to be associated with use of gonadotropin-releasing hormone agonists, as opposed to antagonists, to produce multiple eggs. Patients should discuss options with their fertility doctor and neurologist.
See More Helpful Articles:
Pregnant with MS: Drug Exposure
Drugs to Take (And Not to Take) When Pregnant with MS
Pregnancy, Infertility and Hormones: MS and Motherhood
Breastfeeding and MS Drugs: What Is Safe to Take?
Coyle PK. Management of women with multiple sclerosis through pregnancy and after childbirth. Ther Adv Neurol Disord. 2016;9(3):198–210. DOI:10.1177/1756285616631897