Objective: Although anti-D prophylaxis has greatly reduced the rate of Rh-immunization, there remain women who sensitize during or after pregnancy because of inadequate prophylaxis. The purpose of this study was to compare adherence to prophylaxis recommendations for antenatal and postnatal anti-D immunoglobulin administration.
Methods: We conducted a retrospective cohort study of all pregnancies recorded at the Royal Victoria Hospital between 2001 and 2006 to determine the rates of antenatal and postnatal prophylaxis in Rh(D)-negative women. We compared adherence to anti-D prophylaxis recommendations between our institution's physician-dependent antenatal approach and the protocol-based postpartum approach. Logistic regression analysis was used to estimate the odds ratio and 95% confidence intervals of determinants of non-adherence to current recommendations for anti-D prophylaxis.
Results: Antenatal administration was analyzed in 1868 pregnancies in eligible Rh-negative women. Among these women, 85.7% received appropriate antenatal prophylaxis and 98.5% of eligible women received appropriate postnatal prophylaxis. Factors independently associated with non-adherence to antepartum prophylaxis included first visit in the third trimester (P < 0.001), transfer from an outside hospital (P = 0.03), and physician licensing before 1980 (P = 0.04).
Conclusion: Unlike hospital-based protocol-dependent systems, physician-dependent systems for antenatal anti-D prophylaxis remain subject to errors of omission. A more standardized system is needed to ensure effective antenatal prophylaxis.