[Blood serum levels in mother and child after oral administration of doxycycline ante partum (author's transl)].

After the administration of a single dose of doxycycline to 14 pregnant women shortly before delivery, different concentrations of doxycycline were measured in blood from the umbilical cord after parturition, up to a maximum 54% of the maternal serum concentration. 9 hours after the application of 200 mg doxycycline, a serum level could no longer be detected in the blood from the cord of the fetuses. Serum levels were still demonstrable in the maternal blood 24 hours after the administration. The level of the concentration of doxycycline in the fetal blood was dependent on the level of the concentration of doxycycline in the maternal blood.