Comparison of incidence of pregnancy induced hypertension in gestational diabetes mellitus and healthy pregnant women

Background: Gestational diabetes mellitus (GDM) is defined as carbohydrate intolerance occurring or detected for the first time during pregnancy also hypertension is one of the major complications of pregnancy. Hypertension occurring as a result of pregnancy is called pregnancy-induced hypertension (PIH), which is itself divided into two groups: gestational hypertension and preeclampsia. The aim of this study is to compare the incidence of hypertensive disorders in pregnant women with GDM and healthy group. Methods: In a cohort study, 615 pregnant women including 293 GDM patients as exposed group were recruited. Gestational diabetes mellitus was diagnosed based on Carpenter and Coustan criteria. On the other hand, 322 women with a normal glucose challenge test were chosen as unexposed. Results: Mean age, BMI, and parity in GDM and control groups were 27.64±5.80 and 25.71±4.93 years, 26.98±5.38 and 25.63±5.08 kg/m, and 1.34 ± 0.84 [1(3)] and 0.25±0.43 [1(1)] births, respectively. Women with GDM had a significant higher prevalence of PIH than matched controls [OR=3.18, (95% CI: 1.13-8.94), RR=1.03, (95% CI: 1.004-1.06), P=0.03]. The prevalence of preeclampsia and essential hypertension was also higher in women with GDM than matched controls but not significant. Conclusion: Our results show that hypertensive disorders are more common in women with GDM than in normoglycaemic controls of similar age, parity and BMI. It has been hypothesized that this association, at least in part, could be due to insulin resistance, which is a physiologic phenomenon and adaptation in normal pregnancy but that in the predisposed individual with other risk factors could lead to pathologic procedures for instance the development of PIH, GDM, or both. Correlation does not necessarily imply causation, but the development of possible preventive strategies and therapeutic interventions based on this data could be beneficial