Macrosomic fetuses in diabetic pregnancies develop a unique pattern of overgrowth, involving the central deposition of subcutaneous fat in the abdominal and interscapular areas

Background: Fetal macrosomia, defined as a birth weight ≥ 4,000 g, may affect 12% of newborns of normal women and 15–45% of newborns of women with gestational diabetes mellitus (GDM). The increased risk of macrosomia in GDM is mainly due to the increased insulin resistance of the mother. In GDM, a higher amount of blood glucose passes through the placenta into the fetal circulation. As a result, extra gluPublished online: June 2, 2015 Hua Zhang, MD, PhD, Department of Obstetrics and Gynecology Canada-China-New Zealand Joint Laboratory of Maternal and Fetal Medicine The First Affiliated Hospital of Chongqing Medical University No. 1 Youyi Road, Yuzhong District, Chongqing 400016 (PR China) E-Mail zh2844 @ gmail.com © 2015 S. Karger AG, Basel 0250–6807/15/0666–0014$39.50/0 Key Messages • Fetal macrosomia, resulting from fetal hyperinsulinemia in response to maternal diabetes, might be a predictor of later glucose intolerance. • Maternal diabetes during pregnancy can lead to a transgenerational transmission of diabetes risk. • Fetuses of obese women with gestational diabetes mellitus have a higher risk of developing macrosomia than those of nonobese women with gestational