True about indications for prevention of Rh isoimmunization :

Ans. is b and d i.e. Required when baby is Rh +ve & Mother Rh-ve; and Can be given up to 1 month of age of baby Postpaum prophylaxis If baby is Rh positive and mother Rh negative, 300 pg of Anti D immunoglobulin (IgG) is given to the mother and not infant (provided maternal antibody screening is negative) therefore Option '12' is correct and Option 'a' is incorrect. Post paum prophylaxis is best given within 72 hours after delivery but it can be given till 28 days after delivery Option 'd is correct. "Although Rh lgG generally should be given within 72 hours after delivery, it has shown to be effective in preventing l'oimrritinization if given uoto 28 days after delivery" COGDT 10/e, p 284 Anti D immunoglobulin is not helpful in case of ABO incompatibility. Also Know : Role of post paum prophylaxis : Anti D immunoglobulin given post paum binds to antigen sites on the fetal red cells so that these cells cannot mount an immune response and thus prevent future sensitisation and next pregnancy. If after delivery. mother's ICT is positive or fetus has a positive direct coomb's test, it means that the mother is already immunized. In such cases, there is no point in giving anti D.