[The determination of verapamil in maternal and fetal blood (author's transl)].

During the late first stage of labor and during the second stage of labor seven women in labor received an intravenous infusion during 60-110 minutes of verapamil at 2 g/k/per minute. Immediately following delivery of the infant, maternal and cord blood was drawn and the verapamil level measured by gas chromatography. The serum levels in the maternal blood were from 5.4 to 33.6 ng/ml. (Mean value 19.3 +/- 3.3 ng/ml) and the cord blood concentrations were 4.3-17.8 ng/ml (Mean value 8.5 +/- 1.9 ng/ml). The mean fetal serum level of verapamil was 51.4% of the mean maternal value.