The role of inflammation in cases with gestational diabetes mellitus: Systemic immune inflammatory index according to trimesters

Problem This study aims to investigate the role of the systemic immune‐inflammatory index (SII) in inflammation by analyzing SII values by trimester in gestational diabetes mellitus (GDM). Method of Study Between May 2019 and June 2020, we retrospectively enrolled 467 pregnant women who were followed from the first trimester to delivery in our hospital. We evaluated the sociodemographic characteristics, laboratory test results, SII values, Apgar scores, and newborn birth weights of pregnant women diagnosed with GDM. We also compared the SII values of GDM for the 1st, 2nd, and 3rd trimesters with the control group. Results When examining the SII values of the GDM group in these three trimesters, without including the control group, we found that the SII value of the GDM group in the 3rd trimester was significantly higher than in the 1st trimester, with a gradual increase with each trimester (p = .007). Additionally, the SII value was higher in the GDM group compared to the control group (p = .008). We conducted a Receiver Operating Characteristic (ROC) analysis of the SII value between the groups by trimester. The diagnostic significance of SII between the GDM and control groups was observed in the 3rd trimester, as the area under the curve (AUC) was close to 0.5 and not associated with a specific cutoff value. When examining the relationship between 3rd‐trimester SII and study parameters, we found it had a positive and low correlation with the length of prepartum hospitalization, 50 g Oral Glucose Tolerance Test (OGTT), and maximal vertical pocket. Conclusion SII levels were significantly higher in third‐trimester GDM patients; however, despite elevated levels of inflammation, fetuses did not experience harm.