Effects of pregnancy and breastfeeding on the multiple sclerosis disease course

Multiple sclerosis (MS) commonly affects young women of childbearing age. Thus, the challenges of the disease are often faced simultaneously with the challenges of early adult life and family planning. This has led to great interest in the effects of pregnancy and breastfeeding on MS. It is now well known that the risk of MS relapse declines during pregnancy but increases in the first 3-4 months postpartum. However, important gaps in knowledge remain and are the focus of this review. What factors predict postpartum relapses? Are there modifiable factors, such as breastfeeding, particularly exclusive breastfeeding, that could reduce the risk of postpartum relapses? Does pregnancy or breastfeeding have any long-term effects on MS disease course? What immunological mechanisms underlie the effects of pregnancy and breastfeeding? Answering these questions will improve our ability to care for women with MS and may provide a greater understanding of the pathophysiology of the disease.