The purpose of this review is to give useful information to guide clinicians when treating pregnant women affected by bipolar disorder. This review focuses on mood stabilizers including lithium, sodium valproate, carbamazepine, oxcarbazepine, gabapentin, lamotrigine and topiramate. Data have been extracted from a MEDLINE search. Data from prospective, retrospective and case-control studies as well as systematic reviews, meta-analysis and data from Pregnancy Registry were included. Major congenital malformations as well as specific malformations were reported for each drug. Preliminary findings seem to identify lamotrigine as one of the safest antiepileptic drugs to be used in pregnancy. Teratogenity risk of topiramate is still largely unknown and there are not enough studies to draw even preliminary conclusions. Preliminary studies failed to report an increased risk for major congenital malformations among gabapentin or oxcarbazepine exposed pregnancies. Even if raising less concern when compared to valproate, carbamazepine should be avoided for its documented teratogenity risk. Valproate seems to be the worst considering major congenital malformations, specific malformations as well as its detrimental effects on neurodevelopment. On the other hand, lithium might be considered a good option when treating pregnant women affected by bipolar disorder. Given the limited research on mood stabilizers in pregnancy, clinicians need to be very careful when treating child bearing age women. Clinicians have to balance the potential teratogenity risk against that of untreated mental illness considering individual circumstances such as severity of illness and risk of relapse.