<prompt> Highest transmission of hepatitis B from mother to fetus occurs if the mother is infected during:Ist trimesterIInd trimesterIIIrd trimesterAt the time of implantation  <response>: Viral hepatitis is the commonest cause of jaundice in pregnancy in the tropics.Hepatitis A HAV:Infection is spread by faecal-oral route.Diagnosis is confirmed by detection of IgM antibody to hepatitis A anti HAV Igm.Disease is usually self limited and fulminant hepatitis is rare.Perinatal transmission is rare, chronic carrier state does not exist.The virus is not teratogenic.Pregnant woman exposed to HAV infection should receive immunoglobulin 0.02 mlkg within 2 weeks of exposure. She should also have hepatitis A vaccine single dose 0.06 ml IM. It is safe in pregnancy.Hepatitis B virus HBV:The virus is transmitted by parenteral route, sexual contact, vertical transmission and also through breast milk.The risk of transmission to fetus ranges from 10 in first trimester to as high as 90 in third trimester and it is specially high 90 from those mothers who are seropositive to hepatitis B surface antigen HBsAg and e-antigen HBeAg.Neonatal transmission mainly occurs at or around the time of birth through mixing of maternal blood and genital secretions. Approximately 25 of the carrier neonate will die from cirrhosis or hepatic carcinoma, between late childhood to early adulthood.HBV is not teratogenic. 