Boyne, Michael S.; Thame, Minerva M.; Bennett, Franklyn I.; Osmond, Clive; Miell, John P.; Forrester, Terrence E.
Author Affiliation, Ana.
Tropical Medicine Research Institute; Department of Pathology
The relationship among circulating insulin-like growth factor (IGF) -1, IGF- binding proteins-1 and -2, and birth anthropometry: a prospective study
Journal of clinical endocrinology and metabolism
Date of Publication
Fetal IGF-I is a determinant of birth weight, but whether maternal IGF-I plays a significant role is controversial. We sought to examine the relationships among maternal IGF-I, IGF-binding protein (IGFBP)-1, and IGFBP-2, with maternal and newborn anthropometry, in a cohort of 325 nondiabetic pregnant women of African origin. Blood was collected for IGF-I, IGFBP-1, and IGFBP-2 at 9, 25, and 35 wk gestation and in cord blood at delivery. In the second and third trimesters, maternal IGF-I was significantly correlated (P<0.005) with maternal body mass index and triceps skinfold thickness. Maternal IGFBP-1 and -2 had an inverse correlation (P<0.0001), with maternal anthropometry. Maternal IGF-I at 35 wk, and fetal IGF-I by cord blood were significantly correlated with birth weight (P=0.001 and 0.048, respectively). IGFBP-1 in the third trimester and cord blood were negatively correlated with birth weight (P=0.012 and 0.002). In multiple regression analyses, maternal IGF-I at 35 wk, fetal IGF-I, maternal weight at the first antenatal visit, gender, and gestational age were significant independent factors in the determination of birth weight. In conclusion, maternal IGF-I levels, especially during late pregnancy, positively influence birth weight.....