Taste and endocrine factors in women with gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is hyperglycemia first identified during pregnancy. Many metabolic parameters increase across normal gestation, but may exceed those levels in pregnancies where GDM develops. Studies on the time course and pattern of metabolic factors in GDM are conflicting. Additionally, past research suggests changes in cravings and dietary intake during normal pregnancy and taste alterations in diabetes and pregnancy. Such parameters have been studied only on a limited basis in women with GDM. In this dissertation, we examined metabolic, taste and dietary measures across pregnancy. The temporal profile of insulin, cortisol and leptin was determined in women who developed GDM and those who remained normal glucose tolerant (NGT). Fasting insulin levels were higher at 24-28 weeks gestation than during postpartum in women with GDM, however it was not until 34-38 weeks that insulin differed from postpartum in NGT women. Both pregnant groups showed similar increases in cortisol levels across gestation. From 16-20 weeks to 24-28 weeks, leptin rose rapidly in women with GDM and was marginally higher in GDM women relative to NGT women at 24-28 weeks. By 34-38 weeks, leptin values did not differ between pregnant groups. We also studied pregnancy and GDM effects on sweet taste perception and preference, and examined relationships of taste parameters with circulating hormones. Women with GDM exhibited higher preference for sucrose-sweetened milk as well as positive relationships between liking of glucose solutions and sucrose-sweetened milk and insulin and leptin, respectively. Women with NGT reported higher intake of all sweet food and beverage at 24-28 weeks, primarily as fruit and fruit juice, while women with GDM reported higher frequency of sweet cravings at 34-38 weeks gestation. These results suggest that women challenged with concurrent pregnancy and diabetes exhibit early rises in insulin and leptin during gestation and such endocrine changes may be related to elements of sweet taste. Additionally, during late gestation, although women with GDM report following a carbohydrate controlled diet, they show a higher preference and craving for sweet taste. In GDM, alterations in sweet taste and differences in sweet cravings and food intake may be metabolically or psychologically based.Ph.D.Includes bibliographical references