Comparison of the performance of screening test for gestational diabetes in singleton versus twin pregnancies

Comparing the screening methods for gestational diabetes mellitus before and during the COVID-19 pandemic: A systematic review

BACKGROUND

The oral glucose tolerance test (OGTT) is the gold standard for detecting gestational diabetes mellitus (GDM). However, during the COVID-19 pandemic, screening practices were reevaluated due to the risk of infection associated with the prolonged hospital visit required for the OGTT. Some countries have published novel screening protocols for GDM, suggesting the utilization of hemoglobin A1c (HbA1c), random plasma glucose (RPG), or fasting plasma glucose (FPG) in favor of OGTTs during the pandemic. Therefore, differences in screening methods before and after the epidemic need to be examined.

METHODS

A systematic search was carried out across five electronic databases (Cinahl, Medline, Embase, Pubmed, and Web of Science) between 2016 and 2023. The Critical Appraisal Skills Programme (CASP) checklist for cohort studies was used to evaluate the quality of included papers.

RESULTS

A total of 13 eligible studies were included. Prior to the COVID-19 pandemic, the OGTT was the recommended measure to screen GDM, internationally based on various official guidelines. During the pandemic, it was recommended that HbA1c or FPG, or RPG be used as a substitute for OGTTs. However, the new methods have low sensitivity, may not reflect accurately the prevalence of GDM, and may lead to many false-negative results in women and to adverse pregnancy and neonatal outcomes.

CONCLUSION

The new screening methods for GDM have poor accuracy and a high risk of adverse pregnancy outcomes. Comparatively, targeted screening tests to detect GDM according to the risk level are more effective in an emergency. In the future, the alternatives to OGTTs still need to be further explored in more depth.

Maternal diabetes following gestational diabetes: Does multiple gestation multiply the risk?

OBJECTIVE

To assess whether the risk for future diabetes is higher among women diagnosed with gestational diabetes (GD) during twin versus singleton gestations.

METHOD

A retrospective cohort study was performed including all women who delivered at a tertiary medical center between the years 1991 and 2021 and had at least one GD diagnosis. The first GD diagnosis per women was defined as the index pregnancy. Women diagnosed with GD during multiple gestations were compared with women diagnosed with GD during singleton gestations. The outcomes included first hemoglobin A1C (Hba1C) level > 6.4 mg/dL post partum, and the highest level measured during the follow-up period of up to 30 years. Multivariable logistic and Cox proportional analysis were used to compare the risk between the two groups while adjusting for confounding variables.

RESULTS

The current study included 13 770 mothers, with 458 patients (3.3%) diagnosed with GD during twin gestations and 13 312 (96.7%) during singleton gestations. The mean follow-up was 12.25 ± 9.3 years. Mothers of both groups did not differ in age at index pregnancy; however, mothers of twins were more likely to conceive following fertility treatments. Incidence of diabetes and prediabetes (defined as Hba1C > 6.4 and >5.7, respectively) were lower among the twin-gestation group, both during the 6-month postpartum period (for diabetes: 15.5% vs 22.1%; odds ratio [OR], 0.65 [95% confidence interval (CI), 0.46-0.91]) and during the long-term follow-up (for diabetes: 31.8% vs 40.7%; OR, 0.68 [95% CI, 0.52-0.88]). These results remained significant in the multivariable analysis, while accounting for age, ethnicity, and fertility treatments.

CONCLUSION

GD diagnosis during multiple versus singleton gestations is associated with a lower risk for future diabetes.

Gestational diabetes mellitus and adverse maternal and perinatal outcomes in twin and singleton pregnancies: a systematic review and meta-analysis

OBJECTIVE

This study aimed to assess the risk of adverse maternal and perinatal complications between twin and singleton pregnancies affected by gestational diabetes mellitus and the respective group without gestational diabetes mellitus (controls).

DATA SOURCES

A literature search was performed using MEDLINE, Embase, and Cochrane from January 1980 to May 2023.

STUDY ELIGIBILITY CRITERIA

Observational studies reporting maternal and perinatal outcomes in singleton and/or twin pregnancies with gestational diabetes mellitus vs controls were included.

METHODS

This was a systematic review and meta-analysis. Pooled estimate risk ratios with 95% confidence intervals were generated to determine the likelihood of adverse pregnancy outcomes between twin and singleton pregnancies with and without gestational diabetes mellitus. Heterogeneity among studies was evaluated in the model and expressed using the I2 statistic. A P value of <.05 was considered statistically significant. The meta-analyses were performed using Review Manager (RevMan Web). Version 5.4. The Cochrane Collaboration, 2020. Meta-regression was used to compare relative risks between singleton and twin pregnancies. The addition of multiple covariates into the models was used to address the lack of adjustments.

RESULTS

Overall, 85 studies in singleton pregnancies and 27 in twin pregnancies were included. In singleton pregnancies with gestational diabetes mellitus, compared with controls, there were increased risks of hypertensive disorders of pregnancy (relative risk, 1.85; 95% confidence interval, 1.69-2.01), induction of labor (relative risk, 1.36; 95% confidence interval, 1.05-1.77), cesarean delivery (relative risk, 1.31; 95% confidence interval, 1.24-1.38), large-for-gestational-age neonate (relative risk, 1.61; 95% confidence interval, 1.46-1.77), preterm birth (relative risk, 1.36; 95% confidence interval, 1.27-1.46), and admission to the neonatal intensive care unit (relative risk, 1.43; 95% confidence interval, 1.38-1.49). In twin pregnancies with gestational diabetes mellitus, compared with controls, there were increased risks of hypertensive disorders of pregnancy (relative risk, 1.69; 95% confidence interval, 1.51-1.90), cesarean delivery (relative risk, 1.10; 95% confidence interval, 1.06-1.13), large-for-gestational-age neonate (relative risk, 1.29; 95% confidence interval, 1.03-1.60), preterm birth (relative risk, 1.19; 95% confidence interval, 1.07-1.32), and admission to the neonatal intensive care unit (relative risk, 1.20; 95% confidence interval, 1.09-1.32) and reduced risks of small-for-gestational-age neonate (relative risk, 0.89; 95% confidence interval, 0.81-0.97) and neonatal death (relative risk, 0.50; 95% confidence interval, 0.39-0.65). When comparing relative risks in singleton vs twin pregnancies, there was sufficient evidence to suggest that twin pregnancies have a lower relative risk of cesarean delivery (P=.003), have sufficient adjustment for confounders, and have lower relative risks of admission to the neonatal intensive care unit (P=.005), stillbirths (P=.002), and neonatal death (P=.001) than singleton pregnancies.

CONCLUSION

In both singleton and twin pregnancies, gestational diabetes mellitus was associated with an increased risk of adverse maternal and perinatal outcomes. In twin pregnancies, gestational diabetes mellitus may have a milder effect on some adverse perinatal outcomes and may be associated with a lower risk of neonatal death.

Association between One Abnormal Value on 3-Hour Oral Glucose Tolerance Test and Adverse Perinatal Outcomes in Twin Gestation

AIM

To investigate whether women with twin gestation and one abnormal value on the diagnostic 3-hour oral glucose tolerance test (OGTT) are at an increased risk of adverse perinatal outcomes.

METHODS

This was a retrospective multicenter study of women with twin gestation, comparing four groups: (1) normal 50-g screening, (2) normal 100-g 3-hour OGTT, (3) one abnormal value on the 3-hour OGTT, and (4) GDM. Multivariable logistic regressions adjusted for maternal age, gravidity, parity, previous CDs, fertility treatments, smoking, obesity and chorionicity were used.

RESULTS

The study included 2,597 women with twin gestations, of which 79.7% had a normal screen, and 6.2% had one abnormal value on the OGTT. In adjusted analyses, women with one abnormal value were found to have higher rates of preterm delivery <32 weeks, large for gestational age neonates, and composite neonatal morbidity of at least one fetus, however, similar maternal outcomes as those with a normal screen.

CONCLUSION

Our study provides evidence that women with twin gestation and one abnormal value on the 3-hour OGTT are at an increased risk of unfavorable neonatal outcomes. This was confirmed by multivariable logistic regressions. Further research is needed to determine whether interventions such as nutritional counseling, blood glucose monitoring, and treatment with diet and medication would improve perinatal outcomes in this population.

Screening Accuracy of the 50 g-Glucose Challenge Test in Twin Compared With Singleton Pregnancies

CONTEXT

The optimal 50 g-glucose challenge test (GCT) cutoff for the diagnosis of gestational diabetes mellitus (GDM) in twin pregnancies is unknown.

OBJECTIVE

This work aimed to explore the screening accuracy of the 50 g-GCT and its correlation with the risk of large for gestational age (LGA) newborn in twin compared to singleton pregnancies. A population-based retrospective cohort study (2007-2017) was conducted in Ontario, Canada. Participants included patients with a singleton (n = 546 892 [98.4%]) or twin (n = 8832 [1.6%]) birth who underwent screening for GDM using the 50 g-GCT.

METHODS

We compared the screening accuracy, risk of GDM, and risk of LGA between twin and singleton pregnancies using various 50 g-GCT cutoffs.

RESULTS

For any given 50 g-GCT result, the probability of GDM was higher (P = .0.007), whereas the probability of LGA was considerably lower in the twin compared with the singleton group, even when a twin-specific growth chart was used to diagnose LGA in the twin group (P < .001). The estimated false-positive rate (FPR) for GDM was higher in twin compared with singleton pregnancies irrespective of the 50 g-GCT cutoff used. The cutoff of 8.2 mmol/L (148 mg/dL) in twin pregnancies was associated with an estimated FPR (10.7%-11.1%) that was similar to the FPR associated with the cutoff of 7.8 mmol/L (140 mg/dL) in singleton pregnancies (10.8%).

CONCLUSION

The screening performance of the 50 g-GCT for GDM and its correlation with LGA differ between twin and singleton pregnancies.

Perinatal Outcomes and Related Risk Factors of Single vs Twin Pregnancy Complicated by Gestational Diabetes Mellitus: Meta-Analysis

Objective

Perinatal outcomes and related risk factors of single vs twin pregnancy complicated with gestational diabetes mellitus (GDM) were clarified, providing evidence for developing preventive measures.

Methods

The Chinese National Knowledge Infrastructure (CNKI), China Biology Medicine (CBM), CQVIP, Wanfang, and PubMed databases were searched for published research on the perinatal outcomes and risk factors of single and twin pregnancy complicated by GDM from 2000 to 2021. The quality of the included literature was evaluated according to the Newcastle-Ottawa Scale (NOS). Meta-analysis of the included literature was conducted using RevMan5.3 software.

Results

Relative to a single pregnancy group, infertility, gestational weight gain, and family history of diabetes presented statistical significance in the twin pregnancy group (P < 0.05); gestational age at delivery, cesarean section, preterm birth < 37 weeks, and preeclampsia presented statistical significance in the twin pregnancy group (P < 0.05); and neonatal birth weight, small for gestational age (SGA), neonatal asphyxia, neonatal hypoglycemia, neonatal respiratory distress syndrome (NRDS), neonatal hyperbilirubinemia, and neonatal death presented statistical significance in the twin pregnancy group (P < 0.05).

Conclusion

Infertility, prenatal weight gain, and diabetes in the family are all risk factors for postpartum impaired glucose metabolism in pregnant women with GDM who are carrying twins. The gestational age at delivery, cesarean section, preterm birth < 37 weeks, and preeclampsia of twin pregnant women with diabetes will affect the perinatal status of twin pregnant women. Neonatal birth weight, SGA, neonatal asphyxia, neonatal hypoglycemia, NRDS, neonatal hyperbilirubinemia, neonatal death, etc. should be paid special attention in the perinatal process.

The screening performance of glucose challenge test for gestational diabetes in twin pregnancies: a systematic review and meta-analysis

BACKGROUND

The screening accuracy of the 50 g-glucose challenge test (50 g-GCT) for gestational diabetes (GDM) has been described in singleton pregnancies. Given the physiologic differences and greater increase in insulin resistance in twin compared with singleton pregnancies, the performance of the 50 g-GCT in twin pregnancies may differ.

OBJECTIVES

To perform a systematic review on the screening performance of the 50 g-GCT for gestational diabetes in twin pregnancies.

DATA SOURCES

Ovid Medline, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL).

STUDY ELIGIBILITY CRITERIA, PARTICIPANTS, AND INTERVENTIONS

We included randomized controlled trials or cohort studies that evaluated the screening accuracy of the 50 g-GCT for GDM in twin pregnancies using the two-step approach. The primary outcome was the positive predictive value of the 50 g-GCT for GDM using the 140 mg/dL (7.8 mmol/L) threshold.

STUDY APPRAISAL AND SYNTHESIS METHODS

Methodological quality of included studies was assessed using the QUADAS-2 tool. The positive predictive value (PPV) was pooled for studies that used similar test characteristics.

RESULTS

From 2044 citations, 7 retrospective cohort studies with a total of 55,597 participants were included (6.5% twins and 93.5% singletons). The majority of studies evaluated a 50-g GCT cutoff point of 140 mg/dL. The pooled PPV for a threshold of 140 mg/dL (7.8 mmol/L) for twins was 22.58% (95% CI: 0.1912-0.2647, I²=34.1%). The 50-g GCT screen positive rate in twin pregnancies was higher than that in singleton pregnancies. None of the studies performed routine OGTT.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

The PPV of 50 g-GCT for GDM in twin pregnancies when using a threshold of 140 mg/dL (7.8 mmol/L) is approximately 23%. There is currently no data on the sensitivity and specificity of the 50 g-GCT in twins.

Improved gestational diabetes screening protocol

Objectives

This work aimed to assess the diagnostic validity of two approaches for the screening of gestational diabetes mellitus (GDM) with less discomfort for pregnant women.

Methods

A prospective diagnostic validation study was conducted with 2007 pregnant women. According to risk factors for GDM, women were classified into high-risk and low-risk groups. The current diagnostic procedure, based on oral glucose overload, was followed; simultaneously HbA_1c was tested and an algorithm combining both biomarkers was applied.

Results

In the low-risk group, the Glucose challenge test (GCT) showed a higher area under the curve (AUC 0.953; 95% CI 0.915-0.992) than the HbA_1c test (0.688; 95% CI 0.541-0.834). The best GCT cut-off, 153.5 mg/dL (8.52 mmol/L), showed higher diagnostic validity than that for HbA_1c, 28 mmol/mol (4.75%), and that the algorithm using both tests. In the high-risk group, the GCT showed better diagnostic performance than the HbA_1c and the algorithm; the optimal GCT cut-offs were higher than those recommended in current protocols. 13th week: GCT AUC 0.882 (95% CI 0.843-0.921), HbA_1c AUC 0.624 (95% CI 0.562-0.686), GCT cut-off 140.5 mg/dL (7.8 mmol/L), HbA_1c cut-off 33 mmol/mol (5.15%). 24th week: GCT AUC 0.944 (95% CI 0.925-0.962), HbA_1c AUC 0.642 (95% CI 0.575-0.709), GCT cut-off, 145.5 mg/dL (8.08 mmol/L), HbA_1c cut-off 29 mmol/mol (4.85%).

Conclusions

The GDM diagnostic approach using as the first step the GCT with higher cut-offs showed the best diagnostic validity. Applying these thresholds, 55.6 and 13.7% of 100 g. Oral glucose overloads would have been avoided in low-risk and high-risk pregnant women.

Elevated Alanine Aminotransferase in Early Pregnancy and Subsequent Development of Gestational Diabetes and Preeclampsia

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is now considered as a hepatic manifestation of metabolic syndrome and elevated alanine aminotransferase (ALT) is commonly related to NAFLD in the absence of viral hepatitis or alcohol abuse. Previous studies have indicated that elevated ALT is associated with diabetes or metabolic syndrome in adults, but the clinical significance of ALT or NAFLD in pregnancy has not been well determined. The objective of this study was to determine the association between elevated ALT in early pregnancy and the development of gestational diabetes or preeclampsia in late pregnancy.

METHODS

In this retrospective cohort study, pregnant women who met the following inclusion criteria were included: 1) singleton pregnancy; 2) ALT levels were measured in antenatal outpatient clinic at 4-20 weeks of gestation; 3) patients were screened for gestational diabetes and delivered in Cheil General Hospital and Women's Healthcare Center. Cases with viral hepatitis or other liver diseases were excluded. The early ALT levels were divided into two groups (normal ALT [≤ 95th percentile] and elevated ALT [> 95th percentile]), and the frequency of gestational diabetes and preeclampsia was compared between the two groups of cases. Gestational diabetes was screened and diagnosed by two-step procedure (50 g oral glucose challenge test and 75 g glucose challenge test with World Health Organization [WHO] criteria).

RESULTS

A total of 2,322 women met the inclusion criteria. Cases with elevated early ALT levels (> 95th percentile) had a higher risk of subsequent gestational diabetes and preeclampsia (gestational diabetes by WHO criteria, 2.1% in normal ALT vs. 6.5% in elevated ALT, P < 0.01; preeclampsia, 1.0% in normal ALT vs. 4.1% in elevated ALT, P < 0.05). This relationship between elevated ALT and increased risk of gestational diabetes/preeclampsia remained significant after adjustment for maternal age and pre-pregnancy body mass index.

CONCLUSION

Elevated unexplained ALT in early pregnancy is associated with the risk of subsequent development of gestational diabetes and preeclampsia in late pregnancy.

Prevalence of Gestational Diabetes Mellitus in Eastern and Southeastern Asia: A Systematic Review and Meta-Analysis

AIM

To review the prevalence of gestational diabetes mellitus (GDM) in Eastern and Southeastern Asia.

METHODS

We systematically searched for observational studies on GDM prevalence from January 2000 to December 2016. Inclusion criteria were original English papers, with full texts published in peer-reviewed journals. The quality of included studies was evaluated using the guidelines of the National Health and Medical Research Council, Australia. Fixed effects and random effects models were used to estimate the summary prevalence of GDM and the corresponding 95% confidence intervals (CI).

RESULTS

A total of 4415 papers were screened, and 48 studies with 63 GDM prevalence observations were included in the final review. The pooled prevalence of GDM was 10.1% (95% CI: 6.5%-15.7%), despite substantial variations across nations. The prevalence of GDM in lower- or upper-middle income countries was about 64% higher than in their high-income counterparts. Moreover, the one-step screening method was twice more likely to be used in diagnosing GDM when compared to the two-step screening procedure.

CONCLUSIONS

The prevalence of GDM in Eastern and Southeastern Asia was high and varied among and within countries. There is a need for international uniformity in screening strategies and diagnostic criteria for GDM.

Comparison of perinatal outcomes in late preterm birth between singleton and twin pregnancies

Objective

To determine whether late preterm twin neonates have a more favorable perinatal outcome than singleton late preterm neonates.

Methods

We studied 401 late preterm births between 34+0 and 36+6 weeks of gestation, from January 2011 to December 2014 in our institution. We compared the maternal and neonatal characteristics and perinatal outcomes between singleton and twin pregnancies. Perinatal outcomes included Apgar score, admission to the neonatal intensive care unit (NICU) or special care nursery, duration of NICU stay, and the rate of composite morbidity (antibiotic use, hypoglycemia, hypocalcemia, hyperbilirubinemia requiring phototherapy, respiratory support, and respiratory distress syndrome).

Results

A total of 289 neonates were in the singleton group and 112 in the twin group. The twin group showed smaller mean birth weight despite of longer gestational age at delivery. In addition, there were significant differences in the indication of delivery and cesarean section rate between the 2 groups. Overall, the risk of composite morbidity was similar between 2 groups (odds ratio, 1.4; 95% confidence interval, 0.8 to 2.4).

Conclusion

Our findings suggest that late preterm twins do not show a more favorable outcome than singleton late preterm births.