1 Department of Clinical Medicine - Klinisk Immunologi, Aalborg Sygehus, Department of Clinical Medicine, Health, Aarhus University2 Department of Clinical Medicine - Department of Clinical Immunology, Department of Clinical Medicine, Health, Aarhus University3 unknown4 Department of Clinical Medicine, Health, Aarhus University5 Department of Clinical Immunology, Odense University Hospital6 Syddansk Universitet7 HE Centre - Centre for Health Sciences Education, HE Centre, Health, Aarhus University8 Department of Clinical Medicine, Health, Aarhus University9 Department of Clinical Medicine - Department of Clinical Immunology, Department of Clinical Medicine, Health, Aarhus University10 HE Centre - Centre for Health Sciences Education, HE Centre, Health, Aarhus University
OBJECTIVE: Prenatal and postnatal RhD prophylaxis reduces the risk of RhD immunization in pregnancies of RhD-negative women. Based on the result from prenatal screening for the fetal RHD gene, prenatal RhD prophylaxis in Denmark is targeted to RhD-negative women who carry an RhD-positive fetus. Here, we present a 2-year evaluation of a nationwide prenatal RHD screening. METHODS: Blood samples were drawn from RhD-negative women in gestational week 25. DNA was extracted from maternal plasma and analyzed for the RHD gene. The prenatal RHD results were compared with the serological typing of newborns in 12,668 pregnancies. Early compliance was assessed for 690 pregnancies. RESULTS: The sensitivity for the detection of fetal RHD was 99.9% (95% CI: 99.7-99.9%). Unnecessary recommendation of prenatal RhD prophylaxis was avoided in 97.3% of the women carrying an RhD-negative fetus. Fetuses that were seropositive for RhD were not detected in 11 pregnancies (0.087%). The sample uptake percentage was 84.2%, and the compliance for prenatal anti-D administration was 93.2%. CONCLUSION: The high sensitivity, maintained over 2 years, underlines the reliability of routine prenatal fetal RHD screening in RhD-negative pregnant women, specifically at 25 weeks of gestation. The remaining challenges are logistical and are related to program compliance.
Prenatal Diagnosis, 2014, Vol 34, Issue 10, p. 1000-1005