Rh factor

- another blood system

- named after Rhesus monkey (Macacus rhesus)

- discovered by: Landsteiner and Wiener (1940)

- is based on antgen Rh found in the red blood cells

• Rh⁺ have about 85% of population
• Rh^- have about 15% of population

- antibodies are not present in the blood at normal conditions but they are formed after immunization e.g. after               contact of Rh^- recipient with Rh⁺ donor (it is especially dangerous during pregnancy)

- there are about 13 antigens, the most important is antigen D

Erythroblastis fetalis = Erythroblastosis - condition of in utero baby where byby is Rh⁺ and mother Rh^-. First time around everything is OK, but when the placenta breaks, the baby´s antigen causes the mother´s body to produce antibodies. So, when the mother becomes pregnant again the mother´s body will view baby´s blood as foreign and attack it.