Absence of hepatitis B virus (HBV) DNA in children born after exposure of their mothers to HBV during in vitro fertilization.

During in vitro fertilization, 22 human embryos were exposed to hepatitis B virus (HBV) in contaminated human serum present in the culture medium. All mothers experienced hepatitis B during the first trimester of pregnancy, and two had hepatitis B surface antigen and HBV DNA, as determined by PCR, at the time of delivery. No HBV DNA was found in serum or lymphocytes from the exposed 22 infants. HBV DNA was also absent from one infant at autopsy.