Placental passage of azathiothymidine (AZT) during the second trimester of pregnancy: study by direct fetal blood sampling under ultrasound.

AZT-therapy during pregnancy is actually contraindicated. Two HIV-positive pregnant women who were due to have an induced abortion in the second trimester of pregnancy, were treated with AZT. Blood samples from mothers and fetuses and amniotic fluid samples were taken simultaneously. AZT crossed the placental barrier in the two patients. AZT and GAZT concentrations from the two fetuses were close to those obtained in the two women and in six non-pregnant volunteers.