Amniotic fluid and umbilical cord blood concentrations of antidepressants in three women

Background: Pregnancy and the postpartum period are a time of increased risk for women to develop mood disorders. As such, the reproductive safety data on antidepressant use during pregnancy have rapidly expanded over the last decade; however, there is relatively sparse information on maternal/fetal exchange of these medications and no data reporting their concentrations in amniotic fluid. Methods: We report on three women treated during pregnancy with fluvoxamine, sertraline, and venlafaxine, respectively. Amniotic fluid at amniocentesis and umbilical cord blood and maternal blood at delivery were collected and analyzed for antidepressant concentrations using high performance liquid chromatography with UV detection. Results: Antidepressant and metabolite concentrations were detectable in all amniotic fluid samples, though parent compound concentrations were less than maternal serum and umbilical cord blood concentrations. No adverse effects of the medication were reported. Conclusions: The presence of these antidepressants in amniotic fluid suggests that fetal exposure to these medications is continual and may occur through a variety of paths, thus accounting for increased fetal exposure. These paths include circulatory via placental passage, gastrointestinal via fetal swallowing, and respiratory secondary to fetal lung absorption.