Hepatitis B: Is it possible to vaccinate preterm-infants?

Pre-term infants should be vaccinated at birth and subsequently follow the national hepatitis B vaccination schedule.
For preterm infants weighing under 2,000 g, the initial vaccine dose (birth dose) should not be counted as part of the vaccine series because of the potentially reduced immunogenicity of the hepatitis B vaccine in these infants; three additional doses of vaccine (for a total of four doses) should be administered beginning when the infant reaches one month of age.