Rhesus disease is uncommon these days because it can usually be prevented using injections of a medication called anti-D immunoglobulin.
All women are offered blood tests as part of their antenatal checks and tests to determine whether their blood is RhD negative or positive.
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If the mother is RhD negative, she'll be offered injections of anti-D immunoglobulin at certain points in her pregnancy when she may be exposed to the baby's red blood cells. This anti-D immunoglobulin helps to remove the RhD foetal blood cells before they can cause sensitisation.
If a woman has developed anti-D antibodies in a previous pregnancy (she's already sensitised) then these immunoglobulin injections don't help. The pregnancy will be monitored more closely than usual, as will the baby after delivery.
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