Prenatal diagnosis of macrosomia in pregnancy complicated by diabetes mellitus

OBJECTIVE: To provide a concise review of current practices regarding prenatal diagnosis of excess fetal growth in pregnancies complicated by diabetes mellitus. METHODS: A literature review of relevant publications. RESULTS: Sonographic estimation of fetal size at term is frequently undertaken in the management of diabetic pregnancy. Considerable error in fetal weight estimations, particularly in asymmetrically enlarged fetuses, may limit the accuracy and clinical utility of these measurements. CONCLUSIONS: The limitations and potential inaccuracy of current sonographic methods to detect the large-for-gestational age fetus of a diabetic mother are acknowledged. Customized formulae are of limited benefit so that further study of techniques aimed at assessing fetal fat content and distribution should be undertaken. These methods may improve detection of the large fetus and aid in clinical decision making.