Pregnancy

Does MS affect my ability to get pregnant?

MS does not affect women’s fertility. However, some drugs used to treat MS may have an effect on the menstrual cycle; and some medications are unsafe during pregnancy.

Before you start trying for a family, you should talk to your healthcare provider about any medications you are taking. As some medications are not advised during pregnancy, your healthcare provider may wish to review your prescriptions. If you find you become pregnant unexpectedly and have not had your medications reviewed, it is important that you consult your healthcare provider as soon as possible.

Assisted reproductive technologies (ART)

Though multiple sclerosis does not affect fertility, issues with fertility may exist for other reasons and some women may undergo assisted reproductive technologies to try and conceive. Research has suggested that women living with MS who use ART (including in-vitro fertilization) have an increased risk of relapse following ART, especially in situations where the ART was not successful (pregnancy was not achieved). Possible reasons for risk of increased disease activity may be related to discontinuation of MS disease modifying therapies, increased levels of stress due to infertility and immune changes from hormone-based fertility medications.

What are the risks of my child having MS?

MS is not directly inherited. The general population in North America runs about a 0.1-0.3% risk of developing MS. When a parent has MS, the risk of the child and siblings developing MS is small, increasing to between 1 and 3%. In other words, 97 to 99% will not develop MS.

How will having MS affect pregnancy or giving birth?

Having MS will not directly affect pregnancy, labour or giving birth. Several studies have shown that mothers with MS are just as likely as mothers without MS to have healthy pregnancies and babies, and there is no research to show MS may increase risk of ectopic pregnancy (where a fetus develops in the fallopian tube), miscarriage, premature birth, still-birth or birth abnormalities. During birth itself, problems with weakness, spasms or stiffness in the legs can be managed with the assistance of a nurse or midwife. Many women opt for having an epidural for pain relief during birth. Both epidurals, and anaesthetics for caesarean births, are as safe.

Pregnancy and relapses

There have been many research studies examining the impact of pregnancy on MS. They all show that pregnancy appears to have a positive protective influence on the risk of MS relapses, with relapse rates decreasing, especially during the third trimester (between six and nine months). The reasons for this are not fully understood, but it is thought that hormone levels play a role in allowing the immune system to be more “tolerant”, to stop the body from rejecting the baby. Consequently, the immune system is also less likely to attack the central nervous system in MS. Similar effects are seen in women with other autoimmune conditions.

In the first three months after the baby is born, the risk of relapse increases. This is thought to occur as hormones return to pre-pregnancy levels. Combining the lower risk of relapses during pregnancy and the higher risk of relapses postpartum, overall, the risk of relapses seems similar for women with or without a pregnancy over the same time period.

Symptoms and pregnancy

Although women may have fewer relapses during pregnancy, other MS symptoms can be affected. Many women report that their fatigue becomes worse during pregnancy, but this can be managed by careful time planning. Balance and back pain may also get worse during pregnancy, as the extra weight of carrying a baby can cause a shift in the centre of gravity. Walking aids may be useful at this time to help prevent falls. Any pre-existing bladder and bowel problems may also feel worse or become aggravated during pregnancy. A continence nurse or adviser can offer advice on how to manage these symptoms.

MS Medications and Pregnancy

Before trying for a planned pregnancy, women are typically advised to wait 5 times longer than the medication’s half-life. Half-life refers to the period needed for the concentration of the drug to reach half of its original value. As all drugs are different, the half-life will vary considerably across the MS medications, with waiting times ranging from several days, to several months. The exception is teriflunomide (Aubagio®), where specific procedures are recommended to eliminate the medication prior to conception.

If you become pregnant while taking disease modifying drugs, you should consult your healthcare provider immediately as some of the medications can cause serious harm to the fetus. Steroids are relatively safe during pregnancy though generally avoided during the first three months when fetal organs are developing.

If coming off medications (including antidepressants) poses a serious risk to mother or baby, healthcare providers may advise that they should be continued, or opt for alternative drugs. Your healthcare provider may be able to advise you of ways to manage the symptoms that do not involve medication. All treatments can be resumed immediately after giving birth, although some may not be appropriate if you choose to breastfeed because of the risk of being passed on to the baby via breast milk.