Factors influencing foetal growth in pregnancy complicated by diabetes

Abstract

Background: Gestational diabetes mellitus represents a metabolically altered fetal environment due to an increased maternal supply of carbohydrates. It leads to fetal hyperinsulinemia and stimulates insulin-sensitive tissue, predominantly of the abdomen, resulting in increased fetal growth and delivering large-for-gestational-age newborns. Implications of fetal hyperinsulinemia reach far beyond delivery. Children of mothers with diabetes in pregnancy are predisposed to develop obesity and glucose intolerance through a non-genetic “fuel-mediated” mechanism. The objective of the present study was to study the “fetal growth pattern at different periods of pregnancy complicated by diabetes” and to identify the factors that influence the fetal growth pattern in pregnancy complicated by diabetesMethods: 69 pregnant women with diabetes and 34 pregnant women without diabetes were included in the study by random sampling. Maternal parameters such as age, parity, height, weight at registration, and weight gain during pregnancy, BMI at the time of registration of pregnancy and at the time of delivery, detailed diabetic profile and management including meal plan, insulin administration and dosage were recorded. The fetuses were monitored for Biparietal diameter, abdomen circumference, femur length by 2 ultrasound examinations, one at 18-22 weeks and another at 28-32 weeks were performed. Soon after delivery, sex, gestational age, birth weight, length, head circumference and chest circumference of the newborn were recorded and infants were classified as LGA/SGA/AGA.Results: Maternal age, parity, BMI at the time of delivery and maternal weight gain had significant influence on the birth weight. The abdominal circumference of the fetus detected at 18-20 and 28-32 ultrasound scans had a very significant correlation with neonatal mean birth weight percentile. Conclusions: Not all babies born to diabetic mothers are macrosomic. SGA babies were not uncommon in pregnancies with diabetes especially in those who did not have significant micro vasculopathy. Maternal nutrition plays a significant key role in determining birth weight of babies even in pregnancies complicated by diabetes.