Breastfeeding
The U.S. Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) recommend that all people with hepatitis B should be encouraged to breastfeed their newborns. For guidance you can read the full CDC report and the full WHO report.
The benefits of breastfeeding outweigh any potential risk of infection. Since it is recommended that all infants be vaccinated against hepatitis B at birth, any potential risk is further reduced.
All people should talk to their health care provider about preventing and managing cracked or bleeding nipples to avoid any potential exposure to blood during breastfeeding.
For people taking antiviral treatment, there is data from HIV literature to support the safety of lamivudine and tenofovir during breastfeeding, but please discuss with your doctor if you have concerns.
Additional Resource Links:
WHO: Hepatitis B and breastfeeding (1996)