Effect of screening for red cell antibodies, other than anti-D, to detect hemolytic disease of the fetus and newborn: a population study in the Netherlands.

BACKGROUND: Hemolytic disease of the fetus and newborn (HDFN) is a severe disease, resulting from maternal red cell (RBC) alloantibodies directed against fetal RBCs. The effect of a first-trimester antibody screening program on the timely detection of HDFN caused by antibodies other than anti-D was evaluated. STUDY DESIGN AND METHODS: Nationwide, all women (1,002 in 305,000 consecutive pregnancies during 18 months) with alloantibodies other than anti-D, detected by a first-trimester antibody screen, were included in a prospective index-cohort study. In a parallel-coverage validation study, patients with HDFN caused by antibodies other than anti-D, that were missed by the screening program, were retrospectively identified. RESULTS: The prevalence of positive antibody screens at first-trimester screening was 1,232 in 100,000; the prevalence of alloantibodies other than anti-D was 328 in 100,000, of which 191 of 100,000 implied a risk for occurrence of HDFN because the father carried the antigen. Overall, severe HDFN, requiring intrauterine or postnatal (exchange) transfusions, occurred in 3.7 percent of fetuses at risk: for anti-K in 11.6 percent; anti-c in 8.5 percent; anti-E in 1.1 percent; Rh antibodies other than anti-c, anti-D, or anti-E in 3.8 percent; and for antibodies other than Rh antibodies or anti-K, in none of the fetuses at risk. All affected children, where antibodies were detected, were promptly treated and healthy at the age of 1 year. The coverage validation study showed a sensitivity of the screening program of 75 percent. Five of 8 missed cases were caused by anti-c, with delay-induced permanent damage in at least 1. CONCLUSION: First-trimester screening enables timely treatment of HDFN caused by antibodies other than anti-D, however, with a sensitivity of only 75 percent. A second screening at Week 30 of c- women will enhance the screening program. Severe HDFN, caused by antibodies other than anti-D, is associated with anti-K, anti-c, and to a lesser extent with other Rh-alloantibodies.

Late start of antenatal care among ethnic minorities in a large cohort of pregnant women.

OBJECTIVES: The objectives of this study were to investigate the difference in timing of the first antenatal visit between ethnic groups and to explore the contribution of several noneconomic risk factors. DESIGN: Prospective cohort study. SETTING: All independent midwifery practices in the city of Amsterdam and all six Amsterdam hospitals. POPULATION: Consecutive cohort of pregnant women (n = 12 381). Ethnic groups were distinguished by country of birth. METHODS: Questionnaire data showed possible risk factors for late start. A Cox-proportional hazards model was created with (1) only ethnic group and (2) the addition of all significant risk factors, both time fixed and time dependent. MAIN OUTCOME MEASURES: Gestational age at first visit. RESULTS: The questionnaire was returned by 8267 pregnant women (response rate 67%). All non-Dutch ethnic groups were significantly later in starting antenatal care during the whole duration of pregnancy compared with the ethnic Dutch group (hazard ratio [95% CI]: other Western, 0.83 [0.76-0.90]; Surinamese, 0.62 [0.56-0.68]; Antillean, 0.56 [0.45-0.70]; Turkish, 0.62 [0.55-0.69]; Moroccan, 0.56 [0.52-0.62]; Ghanaians, 0.50 [0.43-0.58] and other non-Western, 0.61 [0.56-0.67]). The range at which 90% were in care varied between 16 weeks and 3 days for Dutch and 24 weeks and 4 days for Ghanaians. These differences disappeared almost totally in the non-Dutch-speaking ethnic groups when the following risk factors were added to the model: poor language proficiency, low maternal education, teenage pregnancy, multiparity and unplanned pregnancy. The differences remained in the Dutch-speaking ethnic groups. CONCLUSIONS: We observed a disturbing delay by all ethnic groups in the timing of their first antenatal visit. In women born in non-Dutch-speaking, non-Western countries, these differences were explained by a higher prevalence of the risk factors: poor language proficiency in Dutch, lower maternal education and more teenage pregnancies. In women born in Dutch-speaking, non-Western countries, the disparities cannot be explained by higher prevalence of these risk factors, indicating that cultural factors play a role.