Every year about 800 chronic hepatitis B infections are identified in the Netherlands as result of the nationwide pregnancy screening. About one-third of these are newly discovered infections. In recent years there has been a marked increase in treatment options for chronic hepatitis B infection using antiviral drugs. Pregnant women can now be treated as well. A pregnant woman with a low viral load does not require immediate treatment, as due to the passive immunisation and active vaccination of the newborn the chances of infection due to perinatal transmission are negligible. Treatment of the mother can therefore be postponed until after the birth. However, when the pregnant woman has a high viral load (>10(9) copies/ml in serum), perinatal transmission can still occur despite vaccination of the newborn. In these women, antiviral treatment in the last trimester of the pregnancy should be considered. At present, experience of treating HBV-infected pregnant women has only been gained with lamivudine. It appears that the quantity of circulating virus decreases due to the treatment. Treatment should always be supervised by a gastroenterologist or an infectiologist. Detection, referral and treatment of the mother and child are described in several guidelines that have recently been updated and harmonized with each other. These include a practice guideline from the Dutch College of General Practitioners, a guideline from the Centre for Infectious Disease Control of the National Institute for Public Health and the Environment, and a guideline from the Netherlands Society of Gastroenterology.