Targeted Routine Antenatal Anti-D Prophylaxis in the Prevention of RhD Immunisation - Outcome of a New Antenatal Screening and Prevention Program

positive fetuses for routine antenatal anti-D prophylaxis (RAADP). positive fetuses. Main outcome measure was the incidence of RhD immunisation developing during or after pregnancy. positive test the women received antenatal anti-D prophylaxis. The incidence of RhD immunisation in the study cohort was 0.26 percent (24/9380) (95% CI 0.15–0.36%) compared to 0.46 percent (86/18546) (95% CI 0.37 to 0.56%) in the reference cohort. The risk ratio (RR) for sensitisation was 0.55 (95% CI 0.35 to 0.87) and the risk reduction was statistically significant (p = 0.009). The absolute risk difference was 0.20 percent, corresponding to a number needed to treat (NNT) of 500. positive fetuses significantly reduces the incidence of new RhD immunisation. The risk reduction is comparable to that reported in studies evaluating the outcome of non selective RAADP to all RhD negative women. The cost-effectiveness of this targeted approach remains to be studied