The correlation of leptin and hCG (human chorionic gonadotrophin) levels in the serum between women with hyperemesis gravidarum and normal control

Abstract

Objective: Hyperemesis gravidarum is a distinct feature occurring in 0.2–1% of all pregnant women and defined as severe form of nausea and vomiting that lead to fluid and electrolyte imbalance, ketonuria, and weight loss during early pregnancy. Hyperemesis gravidarum may be associated with the development or worsening of an eating disorder during pregnancy. Leptin is the 16kDa protein product of the obese gene, which limits food intake and increases energy expenditure and is produced by the human placenta during pregnancy. High leptin level may decrease food intake and metabolic efficiency. The purpose of this study is to evaluate the correlation of leptin and hCG level in the serum of patients with hyperemesis gravidarum compared with a normal control group. Design: Analysis of serum leptin level by sandwich ELISA and serum hCG level by RIA. Materials and Methods: The serum were collected from 16 women with hyperemesis gravidarum and 10 women with normal pregnancy. They were at the gestation stages of 6–9 weeks. The serum leptin and hCG were measured by sandwich ELISA(R&D System) and RIA, respectively. The results for hyperemesis gravidarum group were compared with normal pregnancy group using student t-test. The standard method of correlation(r) analysis was also applied. Results: The level of hCG was significantly higher (p<0.05) in hyperemesis gravidarum group (77982.58± 52163.80mIU/ml) than in normal pregnancy group (28180.95±26834.55 mIU/ml). There was a positive correlation between the total hCG and the gestational age (r=0.6) Although leptin level was higher in hyperemesis gravidarum group than in normal pregnancy group, there was no significant difference between hyperemesis gravidarum group and normal pregnancy group. Conclusion; hCG was involved in the etiology of hyperemesis gravidarum with statistical significance. Leptin did not appear to be responsible for the appetite and dietary intake associated with pregnancy. Although there was no statistical significance, the difference of leptin levels between hyperemesis gravidarum group and normal pregnancy group suggests that leptin might play some role in human pregnancy.