PlGF (placental growth factor) as a predictor of macrosomia at 3rd trimester in pregnancies complicated with diabetes: a multicenter prospective cohort study

Abstract

Background: Fetal macrosomia, defined as birth weight above 95th percentile, is one of the most frequent complications suffered by fetuses of diabetic mothers, happening in up to 45% of these pregnancies. For the infant, macrosomia increases the risk of shoulder dystocia, clavicle fractures and brachial plexus injury and increases the rate of admissions to the neonatal intensive care unit. For the mother, the risks associated with macrosomia are cesarean delivery, postpartum hemorrhage and perineal lacerations. Macrosomic newborns of women with diabetes are at an increased risk of becoming overweight or obese at a young age (during adolescence) and are more likely to develop type II diabetes later in life. Ultrasound follow-up and glucose monitoring during pregnancy are the two tools used in current clinical practice to predict fetal macrosomia. The problem is that, sometimes, despite good ultrasound and glycemic control, diabetic women appear to have macrosomic fetuses. Therefore, new elements are necessary to be included in the prenatal follow-up of diabetic mothers to get a better prediction of fetal macrosomia and achieve better perinatal outcomes. Few studies have evaluated the association of higher PlGF (placental growth factor) levels in maternal blood with higher birth weight, particularly among those with preexisting diabetes. Objective: The aim of this study is to determine the predictive value of PlGF levels in pregnant women with pregestational diabetes (PGDM) and gestational diabetes (GDM) for macrosomia during the second and third trimesters of pregnancy. Design and methods: This is a multicenter observational prospective cohort study. A sample of 410 pregnant women will enter into the study through a non-probabilistic consecutive recruitment. Participants will be pregnant women with diabetes who will be included in two cohorts (A: pregnant women with GDM; B: pregnant women with PGDM) from gestational age between 24-27 weeks to the end of the gestation. We will perform two determinations of PlGF in maternal blood, one at the end of the second trimester and another at the end of third trimester. We will collect the macrosomia rate in each cohort to perform a statistical analysis and confirm the association between PlGF levels and macrosomia adjusting for all the co-variables