[Tissue and body fluid distribution of antibacterial agents in pregnant and lactating women].

OBJECTIVE

To determine the placental transfer and milk excretion of antibacterial agents.

METHODS

A prospective study was conducted in pregnant and lactating women. The concentrations of 13 agents in tissue and body fluid were determined by bioassay or high performance liquid chromatography method.

RESULTS

The results showed that metronidazole, ofloxacin, chloramphenicol, gentamicin and ampicillin crossed blood-placental barrier well, the ratio of fetal tissue or amniotic fluid/maternal serum drug concentration was higher than those of the other agents. The penetration of penicillins (except ampicillin) and cephalosporins was poor, but the drug concentrations were still reached therapeutic levels in the most tissues and body fluids. The placental transfer of amikacin, clindamycin and erythromycin was slightly higher than beta-lactams. The drug concentrations in breast milk was low, except metronidazole and erythromycin, the breast milk levels of the two drugs were more than 100% of maternal serum levels.

CONCLUSION

Based on the results of the study and the consideration of possible adverse effects which may affect both the mother and the developing fetus as well as antibacterial activities of the drugs, the indications and reasonable use of the agents in pregnant and lactating period were recommended.