Effect of zinc supplement on the complications of gestational diabetes

Diabetes, especially the gestational diabetes with its special fetal and maternal disorders, is the most common complication of pregnancy. Both gestational and type II diabetes mellitus are along with a disturbances to insulin secretion as well as insulin resistance. Considering the significant role of zinc in insulin function, the deficiency and importance of this element in gestational diabetes is a matter of consideration. This clinical trial was carried out on 60 pregnants suffering from gestational diabetes, and needing insulin injection from 32nd week to full-term. The patients were divided into two groups the case group (n=30), received daily zinc sulfate (25mg or 5cc) plus insulin and control group (n=30) received daily placebo (5 cc as syrup) plus insulin until the time of delivery. The required insulin dose was regulated through monitoring fasting blood sugar and blood sugar, 2 h postprandial, every two weeks in both groups. These groups were compared in terms of required insulin dose and maternal/fetal complications. Data were analyzed using t-test, OR, CI, Fisher Exact test, Kolmogorov-Smirnov and Chi-Square tests. The required dose of insulin had a significant decrease in the case group compared to the control one (p<0.001). However, the mean change in insulin dose in the case and control group compared to the beginning of study was 8.766 (SD:9.63) and 17.533 (SD: 10.54), respectively. The incidence of macrosomia in the case and control groups was significant (P<0.01). The odds ratio of control group compared to the case group was 7. The preeclampsia prevalence in both groups was not significant. Zinc supplementation in gestational diabetes may lead to the reduction of required insulin dose, incidence of macrosomia and the related complications (e.g., caesarian and delivery dystocia).