THE PLACENTAL-TRANSFER OF CEFUROXIME AT PARTURITION

Maternal and fetal serum concentrations of cefuroxime were determined at birth in 39 women who were given a single intravenous dose of eithe r 750 mg or 1500 mg of cefuroxime before delivery. Mean serum cefuroxi me concentrations in maternal venous and umbilical venous blood were d ose dependent, being significantly higher after 1500 mg of cefuroxime (55.0 mg/l, 95% CI 33.4-80.9 and 19.5 mg/l, 95% CI 9.5-26.3, respectiv ely) than after 750 mg (14.7 mg/l, 95% CI 10.5-21.1 and 8.8 mg/l 95% C I 5.8-9.4, respectively). Antibiotic concentration in maternal blood c orrelated with sampling time but a similar relationship was not found in cord blood. Fetal concentrations did not correlate with mode of del ivery or initial maternal blood pressure. No relationship could be dem onstrated between cefuroxime concentration in maternal or cord blood a nd maternal weight, maternal weight gain, birthweight of baby or volum e of fluid infused prior to epidural anaesthesia. It is concluded that maternal and fetal concentrations likely to be effective for prophyla xis before delivery require a maternal dose of 1500 mg of cefuroxime a nd are independent of these physiological variables.