title: Routine antenatal anti-D prophylaxis--is the protection adequate?
abstract: OBJECTIVE
  Prophylactic anti-D given during pregnancy can be detected in current indirect antiglobulin tests (IAT). Using this to measure the persistence of prophylactic anti-D, this study set out to determine whether there is an association between anti-D detectable at delivery and the RhD status of the foetus and/or the duration of the pregnancy post the standard 28 week dose of routine antenatal anti-D prophylaxis (RAADP). The study also investigated the detection rates of anti-D at delivery when given in a two dose regime or a one dose regime.
  
  
  METHODS
  All IAT screening was undertaken using fully automated Diamed gel technology. The results from 407 women were included in the two dose regime study, and 157 in the one dose regime study.
  
  
  RESULTS
  160/407 (39%) women receiving one dose of prophylactic anti-D had no detectable anti-D at delivery. 123/157 (78%) women on the one dose regime had no detectable anti-D at delivery. No association was found between detectable anti-D at delivery and the RhD status of the infant in either study arm. A strong association was found between detectable anti-D Ig at delivery and the duration of the pregnancy post the 28 week dose in each study arm.
  
  
  CONCLUSIONS
  Our data show that neither the two dose nor the one dose regime appear to provide adequate cover at delivery for a large percentage of pregnant women. This appears to be associated with the duration of the pregnancy past the 28 week dose but not associated with the RhD status of the foetus.
authors: Haematology, Immunology, Transfusion Department, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK. jeni.davies@rdeft.nhs.uk
authors: J
authors: J
authors: Davies
authors: R
authors: R
authors: Chant
authors: S
authors: S
authors: Simpson
authors: R
authors: R
authors: Powell
mesh_terms: D036861:Delivery, Obstetric; D005260:Female; D005333:Fetus; D006801:Humans; D007231:Infant, Newborn; D007518:Isoantibodies / Q000008:administration & dosage / Q000097:blood*; D008297:Male; D011247:Pregnancy; D011292:Premedication; D011295:Prenatal Care / Q000379:methods*; D012203:Rh Isoimmunization; D018029:Rho(D) Immune Globulin / Q000627:therapeutic use*; D015244:Thiorphan / Q000031:analogs & derivatives
chemical_list: D007518:Isoantibodies; C061961:RHO(D) antibody; D018029:Rho(D) Immune Globulin; C072559:retrothiorphan; D015244:Thiorphan