Antibodies detected in samples from 21,730 pregnant women.

Although anti-D is still the main cause of HDN, many other antibodies have been implicated. From September 1995 to April 2000,screening for RBC antibodies was performed on samples from 21,730 pregnant women regardless of RhD type. Standard tube and gel methods were used. Anti-D was identified in 254 samples; other antibody specificities were detected in 376 samples, for a total of 630 antibodies. For this study, 522 antibodies were considered clinically significant. The incidence of potentially clinically significant antibodies was 2.4 percent. The majority belonged to the Rh system, followed by anti-M, -Fya, -S, -Jka, and -Jkb. Among antibodies of no clinical significance, the most frequent were anti- H, -Lea, and -P1.