The probability to evolve to chronic liver disease post HBV infection depends on the age. Between 80 to 90% of children exposed in their first year of life will develop this disease.The serology for HBV must be included in the routine tests of perinatal control. The active and passive immunoprophylaxis prevents the perinatal infection of HBV. It has been documented that pregnant women carrying the HBV chronic infection with high viral burden have a 2030% transmission to the new born child. Those mothers with high viral burden must be treated with lamiduvine after the 28<span name="style_sup">th </span>gestation week. The child of a mother with high viral burden must receive two unique dosages of HBIg and a complete vaccination scheme. Antibody and surface antigen serologic control must be done to the child between 9-15 months of age. Lactancy is not contraindicated.gestation week. The child of a mother with high viral burden must receive two unique dosages of HBIg and a complete vaccination scheme. Antibody and surface antigen serologic control must be done to the child between 9-15 months of age. Lactancy is not contraindicated.

hepatitis B; pregnancy; perinatal hepatitis; lamiduvine; gammaglobulin