Should we continue screening rhesus D positive women for the development of atypical antibodies in late pregnancy?

OBJECTIVE: The purpose of this study was to calculate the incidence of the new development of atypical antibodies (other than anti-rhesus D) in women attending for antenatal care, and to assess the clinical impact and cost-effectiveness of a second test to detect these antibodies. METHOD: A three-year retrospective analysis was undertaken to calculate the number of rhesus positive women who developed new antibodies in the last trimester of pregnancy. RESULTS: Of 13,143 rhesus positive women, 20 (0.15%) developed new antibodies; fetal outcome was not compromised in any of these cases. CONCLUSION: Repeat testing in late pregnancy would appear an unnecessary expense in our population.