Placental transfer of disodium sulbenicillin

The concentrations of sulbenicillin in maternal and fetal blood and in the amniotic fluid compartment were measured in 27 women at parturition. With an intramuscular injection of 2,000 mg of sulbenicillin, the highest concentration of sulbenicillin in maternal blood (109.0 micrograms/ml) was attained at 55 min. The highest concentrations in umbilical cord blood (approximately 25 micrograms/ml) were attained between 1 and 3 h after dosage. The peak concentration in amniotic fluid (27.1 micrograms/ml) was attained approximately 7.5 h after sulbenicillin administration.