A report on 88 pregnancies in Italian woman that were exposed to interferon-beta (average exposure 4 to 5 weeks) has demonstrated that exposure to interferon-beta was not associated with an increased risk of spontaneous abortion. However, it was associated with both a lower baby weight and length. No significant fetal complications, malformations, or developmental abnormalities were noted with a follow-up of 2 years. These findings point to the relative safety of IFNβ foetal exposure of up to 4 weeks during pregnancy. These data will assist woman with MS on interferon beta with difficult decisions with regard to pregnancy.