Endocrine Abstracts

Objective: Gestational diabetes mellitus (GDM) is strongly associated with maternal obesity. Omentin-1 is secreted from the adipose tissue and enhances insulin action. Circulating levels are inversely correlated with body weight, decreased in type 2 diabetes. Pre-existing maternal obesity has been shown to be associated with lower omentin-1 expression in placenta, adipose tissue and maternal plasma. In our previous study, we had shown that plasma omentin-1 level is decreased in women with GDM and increased after delivery. The aim of this study was to assess the maternal plasma omentin-1 level in the first trimester and its predictive value on development of GDM.

Materials and methods: Pregnant women in their first trimester (n=220) were included into the study. Those that developed GDM (n=66) was compared with non-diabetic pregnant women (n=154). WHO criteria was used for the diagnosis of GDM and screening was done at gestational weeks 24–28. Plasma omentin level was measured with ELISA. Fasting blood glucose and insulin were also measured and HOMA-IR was calculated.

Results: Patients with GDM was overweight compared to controls at the beginning of pregnancy (BMI: 28.2±4.4 vs 25.2±3.0). HOMA-IR was higher in GDM group (2.07±1.4 vs 1.40±0.6). Omentin level was not different between groups (2.22±0.8 ng/l vs 2.05±0.9 ng/l). After delivery plasma omentin level increased with a mean level of 166.6±74.1 ng/l. There was no correlation between plasma omentin-1 level and glucose levels during oral glucose tolerance test. Omentin-1 level did not also correlate with BMI, HOMA-IR, and age.

Conclusion: Plasma omentin-1 level during early periods of pregnancy is did not differ between healthy and GDM-developed women. Since decreased levels were observed in GDM patients in previous studies, our findings could indicate that omentin-1 levels decrease as the pregnancy ages or change is only observed when GDM develops.