LEPTIN IN PREGNANCY: ASSOCIATION WITH BONE HEALTH IN THE OFFSPRING

Abstract

<p>Leptin, an adipose derived hormone, has emerged as a regulator of bone metabolism. Recent findings support a role of leptin in the process of fetal bone remodeling during pregnancy; however, the link between maternal leptin during pregnancy and offspring bone status is undocumented. Evidence exists that the intrauterine environment plays a role in programming peak bone mass that is achieved in late adolescence and thus osteoporosis risk later in life. We investigated the association between maternal leptin during the third trimester and offspring bone mass at 3 years of age.</p> <p><strong>Method:</strong> Based on a sub-sample of a prospective birth cohort study, we conducted analysis on 425 mothers from whom maternal blood samples in pregnancy were analyzed for leptin and 25- hydroxyvitamin D, and whole body bone mass by dual energy x-ray absorptiometry were available for both mother and child at 3 years. Data were collected for maternal prepregnancy body mass index (BMI), lifestyle, and nutrition during pregnancy, as well as the child’s nutrition and physical activity at 3 years.</p> <p><strong>Results:</strong> Women obese on entering pregnancy have a two-fold greater circulating leptin during pregnancy than women with normal weight BMIs. Maternal age and skinfold thickness were positively associated with maternal leptin status. However, maternal leptin status was not a significant predictor of offspring BMC z-score at 3 years of age, when adjusted for relevant maternal and child variables. Maternal vitamin D status was also not a predictor of offspring bone status. Rather the key predictors of child BMC z-score were maternal bone mineral density z-score and child’s weight and vitamin D intake at 3 years.</p> <p><strong>Conclusion:</strong> While maternal leptin status during pregnancy is highly variable among women of different BMI categories, in utero exposure to leptin is not a significant factor that influences child bone status at 3 years of age when adjusted for other relevant variables.</p>