Objective To investigate the expression relationship of signal transducer and activator of transcription 3 (STAT3) and long non-coding RNA MEG3 (lncRNA MEG3) in placental tissue of pregnant and lying-in women with gestational diabetes mellitus (GDM).

Methods Sixty-two pregnant and lying-in women with GDM who underwent obstetric examination and in-hospital delivery were gathered as the GDM group, and 68 healthy pregnant women with normal glucose tolerance during the same period served as the control group. The expressions of STAT3 mRNA and lncRNA MEG3 in placental tissue were detected by qRT-PCR method, fasting blood glucose (FPG) and 2h postprandial blood glucose (2hPG) were detected by glucose oxidase method, fasting insulin (FINS) was detected by biochemical analyzer, and insulin resistance index (HOMA-IR) was calculated according to HOMA-IR = FPG × FINS/22.5; Pearson correlation was performed to analyze the correlation between STAT3 mRNA, lncRNA MEG3 expressions and 2hPG, FPG and HOMA-IR in placental tissue of GDM pregnant and lying-in women; multivariate Logistic regression analysis was performed to analyze the influencing factors of GDM in pregnant women.

Results The expressions of STAT3 mRNA and lncRNA MEG3 in placenta tissue, and 2hPG, FPG and HOMA-IR in GDM group were significantly increased than those in control group (P ＜ 0.05). The expressions of STAT3 mRNA and lncRNA MEG3 in the placenta tissue of GDM pregnant and lying-in women were positively correlated (r = 0.504, P ＜ 0.05), and both were positively correlated with 2hPG, FPG, and HOMA-IR (0.475 ≤ r ≤ 0.504, P ＜ 0.01). Both STAT3 mRNA and lncRNA MEG3 were independent risk factors for GDM in pregnant women (B = 0.864, 0.848, P ＜ 0.01).

Conclusion The expressions of STAT3 mRNA and lncRNA MEG3 in the placenta tissue of pregnant and lying-in women with GDM increase, and they are positively correlated. The increased expressions of the two are independent risk factors for GDM in pregnant women.