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What is Perinatal transmission of hepatits B is maximum when infection in mother occurs in and explain in detail?
Perinatal transmission of hepatits B is maximum when infection in mother occurs in 3rd trimester. HBV does not cross the placenta because of its size, and it cannot infect the fetus unless there have been breaks in the maternal-fetal barrier, such as those that occur during amniocentesis. Women who are infected can transmit HBV to the infant during delivery Transmission to fetus ranges from 10% in 1st trimester to 90% in 3rd trimester and it is especially high from those mothers who are seropositive to HbsAg and HbeAg.