Haemolytic Disease of the Newborn, Jaundice & Rhesus
There are three rhesus groups; C,D & E. Mismatch between fetus and mother mean any leaking fetal red cells into maternal circulation sensitize the maternal immune system potentially leading to haemolytic disease
- Conception of Rhesus positive fetus (inherited from father) by Rhesus negative mother
- Fetal Red Blood Cells leak into maternal circulation in sufficient quantities to induce response
- Miscarriage, Termination
- Antepartum haemorrhage
- Invasive testing (amniocentesis)
- Delayed production of IgG Antibodies affect next pregnancy
Risk of producing hetero-rhesus fetus is 15% in caucasians.
Treat with IM Anti-D after any potentially sensitizing event, for instance after the birth of a Rhesus positive child, or during pregnancy. This "cleans up" any fetal blood cells before they can provoke a response. Give a kelihauer test to determine the proportion of fetal cells present.
Note that once sensitized, a woman cannot be desensitized for her next pregnancy, so test the father, and test the mother for anti-D
- McBain RD, Crowther CA, Middleton P. Anti-D administration in pregnancy for preventing Rhesus alloimmunisation. Cochrane Database of Systematic Reviews 2015, Issue 9 http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD000020.pub3/abstract