606: Maternal HBeAg status and hepatitis B viral activity in HBsAg positive mothers

formed by the tissue during the perfusion period of 4 hours were determined in both the maternal and fetal circuits by liquid scintillation spectrometry. Separation of the drugs from their metabolites was achieved by High Performance Liquid Chromatography (HPLC). RESULTS: Following the perfusion period of 4 hours in the maternal to fetal direction,10 4% of Van and 6 2% of Tel (p 0.05) was transferred to the fetal circuit. Van remaining in the maternal circuit amounted to 59 5% as compared to 65 7% for Tel. The tissue retained 31 6% of Van and 29 6% for Tel. The fetal/maternal concentration ratio of Van at the end of experiment was 0.16 0.06 and for Tel 0.097 0.03 (p 0.05). This data suggest low transfer of the two antibiotics to the fetal circuit. The transfer of Van and Tel in the Maternal-toFetal direction was normalized to that of AP and did not reveal a significant difference with their transfer in the Fetal-to-Maternal direction. In addition, neither Van nor Tel was metabolized by the tissue during the perfusion period. CONCLUSION: The data obtained using the dual perfusion model system revealed lower transfer of Tel than Van across human placenta. Supported by NICHD OPRU U10HD047891.