Toward providing parents the option of avoiding the birth of the first child with Cooley's anemia: response to hemoglobinopathy screening and counseling during pregnancy.

Will the development of safe, accurate prenatal diagnosis for Cooley's anemia result in a reduction in the unwanted birth of children with Cooley's anemia in the United States? Since detection of couples at risk only through the birth of an affected child will lead to a minimal reduction in the incidence of the disease, carrier screening will be necessary. A pilot project of prenatal hemoglobinopathy screening is being conducted in Rochester, New York, to answer the question "Should hemoglobinopathy carrier screening and genetic counseling of positives be part of routine prenatal care?" In the first 27 months of this study, 6,641 unselected pregnant women have been screened on the first prenatal visit, regardless of race and ethnic origin. Of these, 304 have been positive for some type of hemoglobinopathy. Of the 293 analyzed here, the proportion coming for counseling was 61% of the total group and 77% of the thalassemia trait subgroup. Of this number, the proportion wanting their mate tested was 98% of the total group and 100% of the thalassemia trait subgroup. The proportion of those counseled whose mate was actually tested was 60% for the total group and 70% for the thalassemia trait subgroup. The proportion of at risk couples wanting amniocentesis (mostly for detection of sickle cell disease) was 61%. We conclude that, when comprehensive hemoglobinopathy screening is incorporated into routine prenatal screening, the majority of positive women make an extra visit to receive an explanation, nearly all women coming for counseling want their mate tested, the majority of mates come for testing, and the majority of couples at risk want amniocentesis. Further, pregnant women with beta-thalassemia trait may be more inclined to act upon identification as a carrier than are positive women at large.