The course of multiple sclerosis is affected by pregnancy, breastfeeding, fertility treatment and oral contraceptives, as well as by the still limited therapeutic options for pregnant women with multiple sclerosis. It has been shown that the annualized relapse rate is reduced during pregnancy, but increased during the early postpartum period. Studies have also shown that breastfeeding in patients with multiple sclerosis is safe. Currently, there are no clear guidelines regarding usage of oral contraceptives. On the other hand, gonadotrophinreleasing hormone (GnRH) agonists should be avoided when treating infertility. Most disease-modifying drugs used in the treatment of multiple sclerosis are not recommended during pregnancy and breastfeeding, excluding glatiramer acetate and interferon, which is safe to use during breastfeeding. Such drugs should be discontinued some time before pregnancy, depending on the rate of their elimination from the body. Relapses during pregnancy and breastfeeding can be treated with pulse steroid therapy; however, such therapy should be avoided during the first trimester of pregnancy. In patients who are breastfeeding, it is recommended to postpone it for at least 4 hours after receiving treatment. Recently, methods for preventing postpartum relapses are being investigated, such as intravenous immunoglobulin, corticosteroid and hormone therapy; however, further research is needed in order to make any final conclusions.