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Learning during genetic counseling is often below expectations, especially in the context of genetic screening. In this report we describe learning as a result of genetic counseling of 298 pregnant women identified as hemoglobinopathy carriers, 234 with sickle cell trait and 64 with beta-thalassemia trait. Counseling was designed to provide the information needed in a simple, clear, and nondirective manner. A special videotape produced for this purpose provided dramatization and a role model illustrating an appropriate response. After viewing the videotape the counselee had an opportunity to question the counselor and to have any misconceptions corrected. Questionnaires revealed significantly increased knowledge as a result of counseling in each of the three hemoglobinopathy subject areas tested-namely, clinical manifestations, genetics, and prenatal diagnosis. Five factors correlated with higher knowledge scores after counseling-namely, a younger patient age, more years of education, knowledge of having trait before this identification, knowledge of the baby's father having trait before counseling, and having no prior children.

Prenatal hemoglobinopathy screening was chosen as a model system for the study of patient receptivity to unsolicited genetic information. Providers of prenatal care in Rochester, NY, were offered free testing of all their prenatal patients and genetic counseling of women found positive. The 18,907 prenatal samples tested in a 5-year period represented 35.1% of the pregnancies in the Rochester metropolitan region. A hemoglobinopathy was found in 810 pregnancies (4.3%). Of the 21 different types of hemoglobinopathies detected, the most common were sickle cell trait (59%), hemoglobin C trait (19%), beta-thalassemia trait (11%), and hemoglobin E trait (5%). At the time of phlebotomy, 75% of the pregnancies were of less than 18 wk duration. Sixty-six percent of the pregnancies occurred in patients unaware of their diagnosis, and 80% occurred in patients unaware that they might be at risk for a child with a serious blood disorder. Of the 810 positive pregnancies, 551 (68%) occurred in patients who came for counseling. Of 453 women counseled during their first screened pregnancy, 390 (86%) said they wanted their partners tested and 254 (55%) had their partner tested. In the 77 pregnancies thus found to be at risk, the couple was too late for prenatal diagnosis in 12 cases, and the condition for which the fetus was at risk was too mild in 12 cases. Prenatal diagnosis was offered in the remaining 53 pregnancies and was accepted by 25 couples (47%). These results indicate that unselected patients in the primary care setting in this region, even though pregnant, are receptive to and utilize genetic information.

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.