Anti-D prophylaxis should be given in all of the following conditions except:
Ans. is c, i.e. Intrauterine transfusion at 28 weeksRef. Dutta Obs. 7/e, p 344; Sheila Balakrishnan, p 369Rh anti D immunoglobulin (IgG) is given to unimmunized Rh negative mothers with Rh positive fetus to prevent active immunization and formation of antibodies against fetal RBC's. The Anti D binds to antigen sites on the fetal red cells so that these cells do not mount an immune response, provided the baby is Rh negative and direct coombs test done on baby is negative. If mother's IUT is positive or fetus has positive direct coombs test, it means mother is already immunized. In such cases there is no point in giving anti D.Indications for Anti D immunoprophylaxis:First trimesterLater pregnancyMiscarriageEctopic (medically or surgically managed)Hydatidiform moleThreatened abortionMedical or surgical MTPChorionic villus samplingMiscarriageAmniocentesisFetal blood samplingAntepartum hemorrhageExternal cephalic versionRoutine antepartum prophylaxisDeliveryIntrauterine fetal deathManual removal of placentaNote: As far as intrauterine fetal transfusion is concerned. It is done as a therapy in case Rh isoimmunization has occurred prior to 34 weeks so, administration of anti-D at this stage will not help.Dose:Ideally amount of Anti D should be calculated according to the volume of fetomaternal bleed by doing a Kleihauer test.Generally:-Gestational age <12 weeks - dose is 50 mg-Beyond 12 weeks - dose is 300 mcgAntepartum prophylaxis: At 28 weeks gestation in a Rh negative patient: Indirect coombs test is done and if antibodies are not detected i.e. patient is unimmunised, Anti D 300 mg is given as antepartum prophylaxis.300 mg of Anti D will neutralize about 15 mL of fetal RBC.
Medical abortion for 63 days pregnancy
Amniocentesis at 16 weeks
Intrauterine transfusion at 28 weeks
Manual removal of Placenta
Pregnancy in Rh-negative Women