Anti-RhD prophylaxis for RhD negative pregnant women

When the father’s red cells are RhD positive and the mother is RhD negative, fetal blood cells will have paternally derived RhD antigen foreign to the mother. If a sufficient volume of fetal RhD positive blood enters maternal circulation, the mother will be sensitised. She will develop anti-RhD IgG antibodies that could endanger her fetus. These antibodies can cross the placenta and cause immune destruction of fetal cells, leading to fetal anaemia, fetal hydrops, and even death in extreme cases. As a rule, maternal rhesus sensitisation occurs during delivery of the placenta, putting any subsequent pregnancy at risk, but sensitisation can also happen during pregnancy.

Births of affected babies are fortunately a thing of the past thanks in part to the development of effective prophylaxis against rhesus disease, which began in the 1960s when Ronald Finn, Cyril Clarke, and colleagues did a series of well controlled studies in which they gave anti-D immunoglobulin concentrate to Liverpool policemen known locally as the “pregnant dads.” They then showed that …