Feto-Maternal Outcomes and Treatment Compliance in Metformin Versus Insulin-Treated Gestational Diabetic and Non-Diabetic Patients at the Rehman Medical Institute, Peshawar

Introduction Gestational diabetes mellitus (GDM) is defined as any degree of glucose intolerance with onset or first recognition during pregnancy. The diagnosis is made on the basis of the oral glucose tolerance test (OGTT) which according to the guidelines of ACOG regards a blood glucose level higher than 190mg/dL after the one-hour test as the criteria for GDM. The first-line agent for GDM is insulin injections; however, it has high costs and also causes its own feto-maternal complications which can include weight gain and polyhydramnios. On the contrary, metformin has fewer complications, is cheaper, and is emerging as a better alternative for the first-line agent for the treatment of diabetes mellitus type 2. GDM had a prevalence of 11.8% in the year 2018 in all trimesters of pregnancy in Pakistan. This study was thus conducted to determine the feto-maternal outcomes of non-GDM and GDM patients on insulin, metformin, and combined treatment respectively admitted to gynecology ward Rehman Medical Institute (RMI) Khyber Pakhtunkhwa, Pakistan in the year 2019. Objectives To determine the feto-maternal outcomes in patients of GDM on metformin treatment and the feto-maternal outcomes in patients of GDM on insulin treatment and to compare the feto-maternal outcomes of mothers with GDM to those without GDM. Methodology This is a retrospective study conducted from January to April 2020 on patients of gestational diabetes mellitus undergoing either metformin, insulin, or both therapies admitted to the gynecology ward, Rehman Medical Institute (RMI). After getting ethical approval from the institutional ethical approval board, data were collected for the entire year of 2019 on the basis of proforma with the variables: demographic data, glycemic control (via OGTT), mode of labor, primary open-angle glaucoma (POAG), and feto-maternal outcomes. Data was entered and analyzed via SPSS version 21.0 (IBM SPSS Statistics for Windows, IBM Corp., Armonk, NY) and the data were run through various tests including descriptive statistics, cross-tabulations, and chi-square. Results were formulated on the basis of these reports which were then presented in the form of graphs and tables. Results Out of 150 mothers who were admitted for delivery at the gynecology ward, 123 (82.0%) women were 30-40 years of age. Non-gestational diabetics patients were 78 (52%) whereas gestational diabetic mothers were 72 (48%); within these GDM-positive mothers 44 (61.1%) were on metformin, 21 (29.1%) were on insulin and seven (9.7%) were on combined treatment. Among modes of delivery, C-section was the most common (113 [76%]), mostly in non-GDM mothers (95 [45.1%]) followed by those on metformin treatment (36 [31.8%]). Considering fetal outcomes there was a significant association between NICU admissions, neonatal jaundice, and breech presentation with insulin-treated mothers (p=0.06, p=0.003, p=0.004, respectively CI=95%). Among maternal outcomes, there was a significant association between pregnancy-induced hypertension (PIH) and insulin-treated patients (p=0.02 CI=95%), premature rupture of membranes (PROM), and metformin-treated patients (p=0.01 CI=95%) whereas eclampsia was significantly associated with mothers not having GDM (p=0.001 CI=95%). Conclusion Based on this preliminary data and considering feto-maternal outcomes, metformin appears to be a safer drug as compared to insulin in the treatment of GDM with more compliance.