Fetal malformation and serum alpha-fetoprotein concentration of diabetic mothers.

Diabetic pregnant patients belong to a high-risk group from a genetic counselling point of view. Therefore serum AFP estimation and ultrasound examination was carried out in 36 diabetic pregnancies, between the 16-20 gestational weeks. Healthy infants were delivered in 28 cases, fetal malformations or diseases were diagnosed in 3 cases (2 exencephaly and 1 polycystic kidney disease), 5 pregnancies ended up with stillbirth and/or severe fetopathy. According to our findings, the feto-maternal AFP balance is altered in poorly controlled diabetic pregnant patients. Therefore the maternal serum AFP concentration does not always reflect the AFP content of amniotic fluid. It is supposed that the low serum AFP concentration in diabetic patients is due to the disturbed AFP balance, which cannot be observed in well controlled pregnant diabetics. In the pregnancy of diabetic mothers both serum AFP and ultrasound examination should be carried out. With further improvement in the preconceptional treatment of diabetic patients not only the number of malformations caused by hyperglycaemia should diminish, but the problems of false negative and false positive serum AFP values caused by the disturbance in carbohydrate metabolism should also become less frequent.