Three cases of delivery under sodium valproate--placental transfer, milk transfer and probable teratogenicity of sodium valproate.

Here is a report of three cases of delivery from women who have taken sodium valproate (VPA). One neonate was born with polydactylism, and we reviewed the congenital malformations in children of mothers who have taken VPA. In the other two cases, we also examined the levels of VPA in the cord serum and breast milk. The levels of VPA in the cord serum were 50 micrograms/ml at 12 hours after the last maternal dose and 75 micrograms/ml at 14 hours after the last maternal dose. The blood levels of VPA in the two mothers were 48-59 micrograms/ml and 55-85 micrograms/ml in their late pregnancy, respectively. The levels of VPA in the breast milk were 2.0-3.5 micrograms/ml and the ratio of VPA in the breast milk to blood was 2-3%. These results suggest the high rate of placental transfer and the low rate of milk transfer of VPA.