Interferon β-1a therapy for multiple sclerosis during pregnancy: an unresolved issue.

On the basis of evidence from clinical trials, contraindications to the use of interferon (INF) are pregnancy, epilepsy and depression. Management of multiple sclerosis during pregnancy is a difficult issue because of pregnancy-related complications and fear of congenital anomalies due to exposure to disease-modifying therapy. In different series, INF therapy was withdrawn before or after variable periods of exposure. This case illustrates a 26-year-old woman diagnosed with relapsing remitting multiple sclerosis who was treated with a weekly regimen of intramuscular INF-β 1a (Avonex). She had received this treatment throughout her pregnancy without any further exacerbations of symptoms or any untoward pregnancy-related complications. In contrast to different series, our patient had the longest exposure to INF-β during pregnancy.