Is in utero early-exposure to interferon beta a risk factor for pregnancy outcomes in multiple sclerosis?

Objective There exist controversial and discrepant results on the risk of spontaneous abortions and teratogenesis induced by interferon treatment in people with MS. Aim of this study is to evaluate risks of the administration of INF beta related not only to the foetus, but also to children development up to 12-months developmental milestones. Methods The study design is retrospective with a follow-up of babies until 18-months of their life. Thirty-eight women out of 240 with MS followed-up at Clinic MS Center of the University Hospital of Catania, Italy became pregnant in the period june 1997-may 2006. Patients were grouped into three arms: in utero exposed to INF beta, never treated and patients who discontinued INF beta before starting conception. Pregnancy outcomes, birth weight, 12-month developmental milestones were collected with an ad hoc questionnaire. Results Newborns of in utero exposed to INF beta patients were little smaller for birth weight (3079.6 +/- 31.3.3 g), but not statistically significant, if compared with the other groups. Developmental milestones appeared within the normal range in all groups. Conclusions Our results were particularly favourable on pregnancy outcomes, because we observed only a smaller birth weight which was not detrimental for the further development of children. We believe that INF beta therapy might not be considered to be a reason for interruption of an intact pregnancy once the drug has been discontinued until delivery.