Delayed emergence of fetal behaviour in type-1 diabetic women.

In pregnancies complicated by maternal type-1 diabetes early fetal growth delay is common and it is suggested that there might be a common mechanism behind this growth delay and the induction of abnormal embryogenesis. As some of the most frequent congenital malformations involve the nervous system, the following study was performed in order to determine whether there is a specific delay in development of neural activity in these embryos and fetuses. In ten women with type-1 diabetes the emergence of specific fetal movement patterns, which are an expression of the functional motor development of the nervous system, was studied weekly by 1 h real-time ultrasound observations, starting at or before 8 weeks of gestation. Data were compared with those obtained in uncomplicated pregnancies. In all women a tight metabolic control was achieved with continuous subcutaneous insulin infusion. In six patients this treatment was started before conception. In all but one of the movement patterns emerging in the first 12 weeks of gestation a delay of 1-2 weeks was found in their first appearance. Only breathing movements were observed for the first time at the same gestational age as in the control group. Plotted according to crown-rump length the emergence of fetal movement patterns occurred, however, almost at the same time as in the control group. It is concluded, that in well controlled diabetic pregnancy there is a delay in functional motor development of the embryonic and fetal nervous system; this delay is not very specific but mostly parallels that of growth; breathing movements emerge relatively early as compared to growth.