Use of oral glucose tolerance testing and HbA1c at 6-14 gestational weeks to predict gestational diabetes mellitus in high-risk women

Treatment Versus Observation in Early Gestational Diabetes Mellitus: A Systematic Review and Meta-analysis of Randomized Controlled Trials

PURPOSE

Early gestational diabetes mellitus (eGDM) refers to elevated blood glucose levels not meeting the criteria for overt diabetes before 20 weeks gestation. Observational studies link eGDM to adverse outcomes, but randomized controlled trial (RCT) evidence on early intervention benefits remains inconclusive. To address this, we performed a systematic review and meta-analysis (SRM) of RCTs on this subject.

METHODS

We searched electronic databases to identify RCTs comparing early treatment vs observation for eGDM. The primary neonatal outcomes analyzed were large-for-gestational age (LGA) and macrosomia. The primary maternal outcome was pregnancy-related hypertension. Secondary neonatal outcomes included neonatal respiratory distress (NRD), neonatal intensive-care unit admission, small-for-gestational age, cord-blood C-peptide ≥90th percentile, and neonatal hypoglycemia. Secondary maternal outcomes were cesarean section (CS), emergency CS, labor induction, preeclampsia, and preterm birth.

RESULTS

Seven RCTs involving 4427 pregnancies were analyzed. The studies differed in their timing and methods of inclusion. Six studies used a combination of lifestyle and pharmaceutical interventions, while 1 relied solely on lifestyle modifications. Early treatment did not reduce LGA [odds ratio (OR) 0.84; 95% confidence interval (CI) 0.53-1.32; P = .44], macrosomia (OR 0.68; 95% CI: 0.43-1.06; P = .09), or pregnancy-related hypertension (OR 1.04; 95% CI: 0.68-1.57; P = .87). Among the secondary outcomes, only NRD was significantly reduced in the treatment arm (OR 0.52; 95% CI: 0.34-0.80; P = .003). However, sensitivity analysis, omitting the lifestyle-only study, demonstrated a lower risk of macrosomia with early intervention (OR 0.55; 95% CI: 0.34-0.91; P = .02).

CONCLUSION

The SRM demonstrates early intervention does not improve most pregnancy outcomes, except NRD. Sensitivity analysis, excluding the lifestyle-only study, additionally revealed a reduction in macrosomia. The findings must be interpreted cautiously due to the variability in study designs. Replication in well-designed multicenter trials is required before clinical application.

Evaluation of an Alternative Screening Method for Gestational Diabetes Diagnosis During the COVID-19 Pandemic (DIABECOVID STUDY): An Observational Cohort Study

Background: To evaluate the impact of applying alternative diagnostic criteria for gestational diabetes mellitus (GDM) during the COVID-19 pandemic on GDM prevalence, obstetrical and perinatal outcomes, and costs, as compared to the standard diagnostic method. Methods: A cohort of pregnant individuals undergoing GMD screening with the alternative GDM method, which uses plasma glucose (fasting or non-fasting) and HbA1c, was compared with a cohort of pregnant individuals undergoing the standard GDM screening method. Both cohorts were obtained from six hospitals across Catalonia, Spain, from April 2020 to April 2022. The primary outcome was large for gestational age rate at birth. The secondary outcomes were composite adverse outcomes, including pregnancy complications, delivery complications, and neonatal complications. The cost differences between screening methods were also evaluated. A similar analysis was performed in the subgroup diagnosed with GDM. Results: Data were collected from 1543 pregnant individuals in the standard screening group and 2197 in the alternative screening group. The standard screening group had a higher GDM diagnostic rate than the alternative screening group (10.8% vs. 6.9%, respectively; p < 0.0001). The primary outcome (large for gestational age rate) was similar between groups: 200/1543 (13.0%) vs. 303/2197 (13.8%). The adjusted OR for this outcome was 1.74 (95% CI: 0.74-4.10). An adjusted analysis showed no differences between groups in the composite adverse outcomes for pregnancy complications (OR: 1.11; 95% CI: 0.91-1.36), delivery complications (OR: 0.95; 95% CI: 0.75-1.19), and neonatal complications (OR: 1.28; 95% CI: 0.94-1.75). Among individuals diagnosed with GDM, the large for gestational age rate was similar between groups: 13/166 (7.8%) vs. 15/151 (9.9%). The OR adjusted for this outcome was 1.24 (95% CI: 0.51-3.09). An adjusted analysis showed no differences in the composite adverse outcomes for pregnancy complications (OR: 1.57; 95% CI: 0.84-2.98), delivery complications (OR: 1.21; 95% CI: 0.63-2.35), and neonatal complications (OR: 1.35; 95% CI: 0.61-3.04). The mean cost (which included expenses for consumables, equipment, and personnel) of the alternative screening method was 46.0 euros (22.3 SD), as compared to 85.6 euros (67.5 SD) for the standard screening method. Conclusions: In this Spanish population during the COVID-19 pandemic, GDM prevalence was lower in the alternative screening group than in the standard screening group. After adjusting for GDM risk factors, outcomes related to obstetrics, delivery, and neonatal complications were comparable between both groups. Finally, the alternative screening method was cheaper than the standard screening method.

Characteristics of Glucose-Lipid Metabolism in Early Pregnancy Among Overweight and Obese Women and Their Predictive Value for Gestational Diabetes Mellitus

Purpose

This study explores the link between women's pre-pregnancy overweight and obesity and glucose and lipid metabolism in their early pregnancy. It assesses how early pregnancy glucose and lipid levels predict gestational diabetes mellitus (GDM) risk, aiming to offer foundational weight management strategies for overweight and obese women to prevent GDM.

Patients and Methods

This study analyzed 2172 pregnant women from 2017 to 2021 at Waitan Street Community Health Service Center, Shanghai, monitoring early pregnancy (7-10 weeks) glucose and lipid levels (TG, TC, HDL-C, LDL-C, FBG, HbA1c) and 24-week OGTT values. Pre-pregnancy BMI categorized participants into overweight and obese, normal, and underweight groups. We compared early pregnancy glycemic and lipid metrics and GDM incidence across groups, examining the relationship between pre-pregnancy BMI and early pregnancy blood metrics. The overweight and obese cohort was further split into GDM and non-GDM groups, comparing early pregnancy glycolipid indicators and assessing their predictive value for GDM development.

Results

In the overweight and obese group, maternal FBG, HbA1c, TG, and LDL-C were higher, while HDL-C was lower than in normal and underweight groups (P<0.05), with a higher GDM incidence (P<0.05). Pre-pregnancy BMI positively correlated with FBG, HbA1c, TG, and LDL-C levels (r=0.556, 0.567, 0.686, 0.214; P<0.05) but not HDL-C. Each 1-unit BMI increase raised GDM risk by 0.204 times (P<0.05). FBG, TG, and LDL-C had high predictive accuracy for GDM in overweight and obese women, with AUCs of 0.991, 0.994, and 0.935, respectively.

Conclusion

Pre-pregnancy overweight and obesity can cause early pregnancy glucose and lipid abnormalities, raising GDM risk. Early testing in such women is a strong predictor for GDM.

Risk factors and diagnostic performance of predictors as a screening technique for gestational diabetes mellitus: a retrospective cross-sectional study

Background

Gestational diabetes mellitus (GDM) is a condition that can have negative impacts on both mother and baby. Detecting GDM early is crucial, and fasting plasma glucose (FPG) has been suggested as a possible screening method. This retrospective cross-sectional study aims to investigate potential risk factors and complications associated with GDM. Additionally, it aims to establish the diagnostic performance of predictive factors as a screening method for GDM.

Methods

Data were collected from the medical records of 247 pregnant women who visited outpatient Obstetrics clinics between 2021 and 2022. The study investigated potential risk factors and complications associated with GDM, including impaired fasting glucose/impaired glucose tolerance (IFG/IGT), family history of diabetes mellitus (DM), and medical conditions. Moreover, the study evaluated the diagnostic performance of potential predictors as screening techniques for GDM.

Results

The study found that IFG/IGT (P<0.001), a history of GDM (P<0.001), and a family history of DM (P=0.022) were significant factors associated with GDM. Healthy individuals had a lower risk of developing GDM (P<0.001). No significant correlation was found between GDM and macrosomia, hypertension, polycystic ovarian syndrome, or other obstetric complications. Although a weak association was observed between fasting blood glucose levels during the first trimester and GDM, it was not significant.

Conclusion

In conclusion, this study found that IFG/IGT and a past history of GDM were significantly associated with GDM. Additionally, a family history of diabetes increased the likelihood of developing GDM, while no significant association was found between GDM and other obstetric complications. Although a weak association was observed between fasting blood glucose levels during the first trimester and GDM, it was not statistically significant.

Establishment of gestational diabetes risk prediction model and clinical verification

OBJECTIVE

The present study aimed to evaluate the risk factors for gestational diabetes mellitus (GDM) and build and validate an early risk prediction model of GDM by comparing the differences in the indicators of the first trimester of pregnancy between pregnant women with GDM and non-gestational diabetes mellitus (NGDM). Thus, this study provided a theoretical basis for early intervention of GDM.

METHODS

A total of 6000 pregnant women who underwent a routine prenatal examination in Qinhuangdao Maternal and Child Health Hospital (Qinhuangdao City, Hebei Province, China) from January 2016-2022 were retrospectively selected and randomly divided into a modeling cohort (4200 cases) and validation cohort (1800 cases) at a ratio of 3:7. According to the results of oral glucose tolerance test (OGTT), they were divided into NGDM and GDM groups. The modeling cohort consisted of 2975 NGDM and 1225 GDM cases, while the validation cohort consisted of 1281 NGDM and 519 GDM cases. The differences in general conditions and laboratory indicators between different groups were compared, and logistic regression analysis was further used to establish a risk prediction model for GDM in the first trimester. The receiver operating characteristic curve (ROC) and Hosmer-Lemeshow (HL) tests were used to evaluate the prediction of the model efficacy.

RESULTS

Age, pre-pregnancy body mass index (BMI), glycosylated hemoglobin (HbA1c), blood uric acid (UA), triglyceride (TG), and high-density lipoprotein cholesterol (HDL-C) in the first trimester were independent risk factors for GDM (P < 0.05). The model equation was Y = 1/{1 + exp[- (- 18.373 + age × 0.065 + BMI × 0.030 + first-trimester HbA1c × 2.519 + UA × 0.014 + TG × 0.224-HDL-C × 0.635)]}. The area under the ROC curve (AUC) of the model cohort was 0.803 (0.788-0.817), the sensitivity was 72.0%, and the specificity was 73.5%. The AUC of the validation cohort was 0.782 (0.759-0.806), the sensitivity was 68.6%, and the specificity was 73.8%. The P values of the HL test in both the training and validation sets were > 0.05, indicating a satisfactory model fit.

CONCLUSION

Age, pre-pregnancy BMI, HbA1C in early pregnancy, blood UA, TG, and HDL-C are independent risk factors for GDM. The risk prediction model established by combining age, pre-pregnancy BMI, and laboratory indicators in the first trimester can provide a theoretical basis for early screening, monitoring, and intervention of GDM high-risk pregnant women.