[Prenatal diagnosis of hemoglobinopathies in the 1st and 2nd pregnancy trimesters].

Fetal diagnosis of haemoglobinopathies, mainly thalassaemia, is widely used for the prevention of these diseases. Since 1975 fetal diagnosis has been carried out in the second trimester of pregnancy (18th - 22th week) on fetal blood samples obtained by fetoscopy or placentocentesis. The biochemical technique most commonly employed has been represented by carboxymethylcellulose chromatography and more recently in our center by isoelectric focusing of haemoglobins which is a faster and cheaper technique. First-trimester fetal diagnosis is now feasible by DNA analysis on chorionic villi. The Milan center experience in second trimester fetal diagnosis of haemoglobinopathies on more than 300 cases and the preliminary data on first trimester diagnosis are reported.