Serum Neuropeptide Y and Leptin Levels compared between Non-pregnant and Pregnant Women in Overall, Non-obese, and Obese Subjects

Objective: The primary objective of this study was to compare serum NPY and leptin levels between non-pregnant and pregnant women in overall, non-obese, and obese subjects. The secondary objective was to compare these peptides between non-obese and obese pregnant women. Methods: Fasting venous blood was collected from non-pregnant women before open abdominal surgery and from pregnant women when admitted to the delivery room during the latent phase of labor. Results: There were 12 non-obese and 14 obese subjects in the non-pregnant group and 9 non-obese and 30 obese subjects in the pregnant group. Systolic blood pressure (SBP) was comparable, but heart rate (HR) was higher in pregnant compared to non-pregnant women. Mean±S.E.M serum NPY levels were lower in the pregnant than in the non-pregnant group in overall (0.54±0.02 and 1.34±0.08, respectively), non-obese (0.53±0.05 and 1.23±0.14, respectively), and obese (0.54±0.03 and 1.43±0.09, respectively) subjects (p<0.01 for all), but these were comparable between obese and non- obese pregnant subjects. Serum NPY was positively correlated with SBP (R=0.281, p<0.05), but negatively correlated with HR (R=-0.324, p<0.01). Serum leptin levels were not different between pregnant and non-pregnant groups, but were significantly higher in obese than non-obese pregnant subjects (p<0.001). Serum leptin levels were positively correlated with body weight, BMI, waist and hip circumferences in overall and pregnant subjects (p<0.001 all). Conclusion: In pregnancy, decreased NPY levels might be associated with inhibition of SBP rising as well as increased HR. Leptin levels might not be associated with pregnancy, but associated mainly with obesity