The in utero maternal metabolic environment is important relative to both short and long term development of the offspring. Although poor fetal growth remains a significant factor relative to long-term outcome, fetal overgrowth is assuming greater importance because of the increase in obesity in the world’s populations. Maternal obesity and gestational diabetes are the most common metabolic complications of pregnancy related to fetal overgrowth and more specifically adiposity.
Women with gestational diabetes have increased insulin resistance and inadequate insulin response compared with weight-matched controls. Gestational diabetes increases the risk of maternal hypertensive disease (preeclampsia) as well as cesarean delivery. At birth the neonate has increased adiposity and is at risk for birth injury. Multiple studies have reported that children of women with gestational diabetes have a greater prevalence childhood obesity and glucose intolerance; even at glucose concentrations less than currently used to define gestational diabetes, compared with normoglycemic women.
Obese women also have increased insulin resistance, insulin response and inflammatory cytokines compared with average weight women both before and during pregnancy. They too are at increased risk for the metabolic syndrome-like disorders during pregnancy that is hypertension, hyperlipidemia, glucose intolerance and coagulation disorders. Analogous to women with gestational diabetes, neonates of obese women are heavier at delivery because of increased fat and not lean body mass. Similarly, these children have an increased risk of childhood adiposity and metabolic dysregulation. Hence, the preconceptional and perinatal period offers a unique opportunity to modify both short and long term risks for both the woman and her offspring.