Sonographic Assessment of Growth of the Fetal Head in Diabetic Pregnancies Compared with Normal Gestations

Abstract

A longitudinal ultrasound study was conducted in 45 insulin-dependent diabetic patients who maintained good glycemic control (mean plasma glucose less than 120 mg/dl) throughout most of their pregnancy in order to assess growth of the fetal head in the presence of euglycemia. Patients with and without vasculopathy were found to be comparable with regard to their glycemic control, medical and obstetric complications, as well as incremental growth and the velocity of growth of the fetal biparietal diameter (BPD). When compared with the control group, the velocity of growth of the BPD was not significantly different throughout pregnancy. However, the actual increment in BPD growth remained less than that of the control fetuses, especially during the second trimester when a significant statistical difference was found. Possible explanations may include delayed ovulation, reduced growth velocity in the first trimester, or constitutionally smaller embryos among the diabetic group. The pattern of BPD growth among diabetics was best described by a third degree polynomial regression equation. These results demonstrate that in well-controlled diabetics, although the increment in BPD was less than controls, the growth pattern of the fetal BPD was similar among the White classes B to FR, and the velocity of growth of the BPD was similar among diabetics and nondiabetics.