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Objective: National audit of informed choice in antenatal screening for thalassaemia., Design: Audit from the UK Confidential Enquiry into Counselling for Genetic Disorders., Setting: Thalassaemia module of the UK Confidential Enquiry into Counselling for Genetic Disorders., Subjects: 138 of 156 couples who had had a pregnancy affected by a major beta thalassaemia from 1990 to 1994., Main Outcome Measures: How and when genetic risk was identified for each couple, and whether and when prenatal diagnosis was offered., Results: Risk was detected by screening before or during the first pregnancy in 49% (68/138) of couples and by diagnosis of an affected child in 28% (38/138) of couples. Prenatal diagnosis was offered in 69% (274/400) of pregnancies, ranging from 94% (122/130) for British Cypriots to 54% (80/149) for British Pakistanis and from 90% in the south east of England to 39% in the West Midlands. Uptake of prenatal diagnosis was 80% (216/274), ranging from 98% (117/120) among British Cypriots in either the first or second trimester to 73% (35/48) among British Pakistanis in the first trimester and 39% (11/28) in the second trimester. A demonstrable service failure occurred in 28% (110/400) of pregnancies, including 110 of 126 where prenatal diagnosis was not offered and 48 of 93 that ended with an affected liveborn infant., Conclusion: Although antenatal screening and counselling for haemoglobin disorders are standard practices in the United Kingdom, they are delivered inadequately and inequitably. An explicit national policy is needed, aiming to make prenatal diagnosis in the first trimester available to all couples and including ongoing national audit.

A simple, fast, and reliable two step procedure for the detection of non-alpha-thalassaemias in mass screening programmes is presented. Step 1 consists of a study of red cell morphology and a one tube red cell osmotic fragility tests. This step eliminates the non-thalassaemic samples; the rest are processed through step 2, consisting of determination of red cell indices and haemoglobin studies. Over the past seven years this procedure has been used at this centre in mass screening secondary school students in Latium. Blood samples from 289 763 students were examined, and 6838 cases of thalassaemia detected. It is estimated that 0.35 +/- 0.25% of subjects with thalassaemia escaped detection by this procedure.

In the 1975 to 1976 school year, under the auspices of the Health Authorities of the Latium Region, the Rome Microcythaemia Centre carried out for the first time a partial screening survey of thalassaemia carriers among the students of the compulsory intermediate school in Latium. This work was the beginning of a new preventive school health service aimed at the prophylaxis of Cooley's disease. In 23 places investigated in Latium, 17724 students were examined, 13354 of whom were in Rome and 4370 elsewhere. The mean percentage of co-operation was 70% and the mean percentage of thalassaemia 2.42%. Thalassaemic students were invited to attend the centre for a check-up along with their families: about half had already come in by the end of June 1976. All students examined, whether normal or thalassaemic, have received written results of the tests. The screening survey aroused notable interest and obtained wide approval both at school and at home. The news of being thalassaemia carriers, even if not welcome, was never the cause of family tragedy.

Since 1975 the Rome Microcythaemia Centre has carried out every year, under the auspices of the health authorities of the Latium region, a screening of thalassaemics among intermediate schoolchildren of Latium. From these campaigns, knowledge about thalassaemias among the young adult population has grown which, in its turn, has resulted in screening of these young adults. Through screening in schools between 1975 and 1982, of 289 763 students examined, 6838 thalassaemics were identified, 6045 of whom were beta- or delta beta-thalassaemics. The total number of young thalassaemics who are identified at present in the Centre through screenings of schoolchildren and young adults is about 3300 per year. Furthermore, from January 1980 to April 1983, 110 prospective couples of child-bearing age at risk (94 of whom originated from Latium) were identified at the Centre, and five homozygous fetuses (three of which originated from Latium) were diagnosed. These data derive from an area in which the frequency of thalassaemia is only 2.4%, and they show that the programme in Latium for the prevention of Mediterranean anaemia has been successful.