When is anti-D injection recommended for rhesus incompatibility?

Rhesus status describes a protein on red blood cells. If a rhesus-negative pregnant person carries a rhesus-positive baby, fetal cells entering the maternal bloodstream can trigger antibodies. Anti-D contains protective antibodies that reduce the chance of sensitisation. Blood-group testing and an antibody screen guide the decision; anti-D is not used to remove antibodies that have already formed.

Attend blood-group and antibody testing as part of pregnancy care. Tell your maternity team promptly about vaginal bleeding, abdominal injury, invasive procedures, pregnancy loss, or a suspected ectopic pregnancy, because timing can affect the plan. Keep a record of any anti-D you receive and follow the advice given after birth. See [Anti-D Injection](/treatments/pregnancy-and-birth-care/anti-d-injection/) for more information.

Contact your maternity service urgently after bleeding, a fall or blow to the abdomen, severe abdominal pain, or fluid loss. Seek emergency help for heavy bleeding, fainting, or severe pain. These symptoms need assessment independently of rhesus status.

Ask whether your antibody screen is negative, which pregnancy events require anti-D, how quickly to report them, and whether testing is needed after delivery.