Treatment

Preventative measures for Rhesus disease of the newborn was initiated in 1970. 500IU of anti-D Rh gammaglobulin is administered to each Rhesus negative non-sensitized woman who delivers a rhesus positive child, has an abortion, an amniocentesis, chorionic villus sampling, or external cephalic version

• removes fetal cells before they can sensitize.
• administration can be titrated to need by measuring the amniotic fluid optical density at 450nm, the wavelength of bile pigment produced by haemolysis.
• alternatively, cordocentesis to measure fetal haemoglobin levels is carried out in some centres. These techniques reduced the incidence of Rhesus haemolytic disease, from 0.52 stillbirths per 1000 total births in 1968 but only 0.16 per 1000 in 1975.

After birth, depending on the severity of the disease, the neonate might undergo phototherapy, exchange transfusion, or drugs to counter cardiac failure such as diuretics.

There is some controversy as to the amount of expensive anti-D immunoglobulin that should be administered. The 500IU U.K. dose only eliminates 4mls of Rh D positive cells. This suffices for 99.3% of 'at risk' pregnancies. Doses of 1,000 to 1,500 IU are used in other parts of Europe from paid donors (1)

Reference:

• Letsky, E., deSilva, M. (1994). Preventing Rh immunisation. BMJ; 309: 213-214.