Highest transmission of hepatitis B from mother to fetus occurs, if the mother is infected during:
The virus is transmitted by parenteral route, sexual contact, veical transmission and rarely breast milk. The risk of transmission to fetus ranges from 10% in 1st TM to as high as 90% in 3rd TM. It is specifically high (90%) from those mothers who are seropositive to hepatitis B surface Antigen(HBsAg) and e-antigen(HBeAg) Reference: Textbook of Dutta,9th edition, page 271
1st trimester
IInd trimester
IIIrd trimester
At the time of implantation
Medical, surgical and gynaecological illness complicating pregnancy