Diagnostic ability of elevated 1-h glucose challenge test

Impact of gestational diabetes mellitus on neonatal outcomes in small for gestational age infants: a multicenter retrospective study

OBJECTIVE

To evaluate obstetric and perinatal outcomes among small for gestational age (SGA) infants born to patients diagnosed with Gestational diabetes mellitus (GDM).

MATERIALS AND METHODS

A multicenter retrospective cohort study between 2005 and 2021. The perinatal outcomes of SGA infants born to patients with singleton pregnancy and GDM were compared to SGA infants born to patients without GDM. The primary outcome was a composite adverse neonatal outcome. Infants with known structural/genetic abnormalities or infections were excluded. A univariate analysis was conducted followed by a multivariate analysis (adjusted odds ratio [95% confidence interval]).

RESULTS

During the study period, 11,662 patients with SGA infants met the inclusion and exclusion criteria. Of these, 417 (3.6%) SGA infants were born to patients with GDM, while 11,245 (96.4%) were born to patients without GDM. Overall, the composite adverse neonatal outcome was worse in the GDM group (53.7% vs 17.4%, p < 0.01). Specifically, adverse neonatal outcomes such as a 5 min Apgar score < 7, meconium aspiration, seizures, and hypoglycemia were independently associated with GDM among SGA infants. In addition, patients with GDM and SGA infants had higher rates of overall and spontaneous preterm birth, unplanned cesarean, and postpartum hemorrhage. In a multivariate logistic regression assessing the association between GDM and neonatal outcomes, GDM was found to be independently associated with the composite adverse neonatal outcome (aOR 4.26 [3.43-5.3]), 5 min Apgar score < 7 (aOR 2 [1.16-3.47]), meconium aspiration (aOR 4.62 [1.76-12.13]), seizures (aOR 2.85 [1.51-5.37]) and hypoglycemia (aOR 16.16 [12.79-20.41]).

CONCLUSIONS

Our study demonstrates that GDM is an independent risk factor for adverse neonatal outcomes among SGA infants. This finding underscores the imperative for tailored monitoring and management strategies in those pregnancies.

Effect of Lockdown Period of COVID-19 Pandemic on Maternal Weight Gain, Gestational Diabetes, and Newborn Birth Weight

OBJECTIVE

 This study aimed to determine whether the lockdown period of the initial novel coronavirus disease 2019 (COVID-19) surge in New York affected gestational weight gain (GWG), newborn birth weight (BW), and the frequency of gestational diabetes mellitus (GDM). Maternal and newborn outcomes during the first wave of the pandemic were compared with those during the same timeframe in the previous 2 years.

STUDY DESIGN

 Retrospective cross-sectional study of all live singleton term deliveries from April 1 to July 31 between 2018 and 2020 at seven hospitals within a large academic health system in New York. Patients were excluded for missing data on: BW, GWG, prepregnancy body mass index, and gestational age at delivery. We compared GWG, GDM, and BW during the pandemic period (April-July 2020) with the same months in 2018 and 2019 (prepandemic) to account for seasonality. Linear regression was used to model the continuous outcomes of GWG and BW. Logistic regression was used to model the binary outcome of GDM.

RESULTS

 A total of 20,548 patients were included in the study: 6,672 delivered during the pandemic period and 13,876 delivered during the prepandemic period. On regression analysis, after adjustment for study epoch and patient characteristics, the pandemic period was associated with lower GWG (β = -0.46, 95% confidence interval [CI]: -0.87 to -0.05), more GDM (adjusted odds ratio [aOR] = 1.24, 95% CI: 1.10-1.39), and no change in newborn BW (β = 0.03, 95% CI: -11.7 to 11.8) compared with the referent period. The largest increases in GDM between the two study epochs were noted in patients who identified as Hispanic (8.6 vs. 6.0%; p < 0.005) and multiracial/other (11.8 vs. 7.0%; p < 0.001).

CONCLUSION

 The lockdown period of the pandemic was associated with a decrease in GWG and increase in GDM. Not all groups were affected equally. Hispanic and multiracial patients experienced a larger percentage change in GDM compared with non-Hispanic white patients.

KEY POINTS

· The COVID-19 lockdown was associated with decreased GWG and increased GDM.. · No change in newborn BW was seen during the lockdown.. · Overall, the lockdown did not have a large clinical effect on these pregnancy outcomes..

Prevalence and Risk Factors of Confirmed Gestational Diabetes Mellitus Among Pregnant Women With Prior Positive Screening: A Case-Control Study

BACKGROUND

 Saudi Arabia has a higher rate of gestational diabetes mellitus (GDM) than most other countries. There is a paucity of data on the risk factors for GDM, particularly positive screening for diabetes in the initial period of pregnancy.

OBJECTIVES

 The aim of this study was to determine the prevalence of confirmed GDM in pregnant women who initially screened positive for GDM, as well as to identify its association with age, nationality, and clinical risk factors.

PATIENTS AND METHODS

 This case-control study was conducted retrospectively at a tertiary referral center in Jeddah, Saudi Arabia. It included pregnant women who were referred between January 2019 and December 2022 after having tested positive on a 50 g oral glucose tolerance test (OGTT). They subsequently underwent a 75 g or 100 g confirmatory OGTT at our center. The sociodemographic and clinical characteristics of those with confirmed GDM (cases) and those with negative confirmatory OGTT (controls) were compared.

RESULTS

 The majority of participants (75.4%) had confirmed GDM. However, there were no significant differences between cases and controls with regard to age, nationality, or clinical or pregnancy-related factors. Of note, the cohort was characterized by high gravidity and high parity, which may indicate susceptibility to GDM.

CONCLUSION

 The study findings support the usefulness of the 50 g OGTT for the screening of pregnant women at high risk for GDM. In addition, high gravidity and parity may also be risk factors for GDM, warranting closer monitoring for GDM and further research in a high-natality population such as that of Saudi Arabia.

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.

Retrospective review of GCT cutoff value based on pre-pregnancy BMI class in patients with GDM

OBJECTIVES

To determine the optimal glucose challenge test (GCT) cutoff value for the screening of gestational diabetes mellitus (GDM) based on pre-pregnancy BMI.

METHODS

An-IRB approved retrospective cohort analysis of singleton pregnancies at a large tertiary healthcare center from January 2004 to December 2020 was performed. The first GCT value completed between 20 and 32 weeks was used. Using a receiver operator curve (ROC), we sought to determine the optimal GCT cutoff value for each BMI category that would predict the development of GDM. Youden Index was used to determine optimal cut-point of GCT values for each BMI class.

RESULTS

A total of 23,550 patients with a GCT value were identified. Of those, 1,676 (7.1%) were diagnosed with GDM. 513 (30.6%) with normal BMI, 449 (26.8%) overweight, 347 (20.7%) class I obese, 210 (12.5%) class II obese, and 157 (9.4%) class III obese patients were diagnosed with GDM. Gestational diabetes was predicted at GCT cutoff value of 130 mg/dL with an area under the curve (AUC) of 0.92 (BMI <25), 131 mg/dL with an AUC of 0.92 (overweight BMI), 131 mg/dL with an AUC of 0.89 (class I BMI), 133 mg/dL with an AUC of 0.88 (class II BMI), and 131 mg/dL with an AUC of 0.88 (class III BMI).

CONCLUSIONS

AUC ranged from 0.88 to 0.92 with 93% or greater sensitivity for GCT cutoff value across each of the BMI categories. The findings support a GCT cutoff value of 130 mg/dL for GDM screening regardless of BMI.

Screening for gestational diabetes mellitus and hyperglycemia in pregnancy with the glucose challenge test administered in early pregnancy

OBJECTIVE

To determine the cut-off value for the 75-g glucose challenge test administered in early pregnancy to screen for gestational diabetes mellitus and abnormal carbohydrate metabolism in pregnancy.

METHODS

A prospective study involving 1500 antenatal patients attending a community hospital. Patients were screened with the 75-g 1-h glucose challenge test in early pregnancy and subsequently tested with the 75-g 2-h glucose tolerance test to diagnose gestational diabetes mellitus. Statistical methods were employed to determine the optimal plasma glucose cut-off value for a positive result in early pregnancy.

RESULTS

A glucose challenge test value of 6.0 mmol/L (108 mg/dl) or more was selected as the preferred cut-off level for further testing with a sensitivity of 83.5% (95% confidence interval [CI] 77.0%-88.9%) and specificity of 49.2% (95% CI 46.5%-52.0%).

CONCLUSION

An early pregnancy glucose challenge test reading of 6.0 mmol/L (108 mg/dl) or more is effective in screening for gestational diabetes mellitus; a value of 10.0 mmol/L (180 mg/dl) or more is effective for finding pre-pregnancy abnormalities of carbohydrate metabolism. The false-positive glucose challenge test diagnoses gestational hyperglycemia, the treatment of which will improve perinatal outcome. Further testing based on risk factors will exclude a false-negative glucose challenge test. A combination of universal early pregnancy screening and selective risk-factor testing is recommended to detect the full range of abnormalities of carbohydrate metabolism encountered in pregnancy.

The association between a previous uneventful vaginal delivery of a macrosomic neonate and future shoulder dystocia

OBJECTIVE

To examine the association between vaginal delivery of a previous macrosomic neonate (birthweight (BW)≥ 4000) among non-diabetic women and the rate of shoulder dystocia (SD) in the subsequent pregnancy.

STUDY DESIGN

A historical prospective cohort study in a university affiliated medical center from 2005 to 2019. Women who had a singleton pregnancy and two consecutive deliveries in our medical center were included. Women with previous GDM, SD or cesarean delivery were excluded. Univariate analysis was followed by multivariate logistic regression.

RESULTS

A total of 38,942 women were included. SD incidence among the subsequent pregnancies was 0.44 % (172 women). In univariate analysis women with previous delivery of large neonates: BW≥90th percentile for gestational age and BW ≥ 4000 g had higher risk for subsequent SD (odds ratio 2.69 [95 % confidence interval 1.89-3.84], p < 0.01 and 2.71 [1.66-4.44], p < 0.01, respectively). However, a backward stepwise multivariate logistic regression model adjusted for significant confounders for SD in the univariate analysis, showed that women with a previous delivery of macrosomic neonate ≥4000 g were not found to have higher or lower risk for SD in the subsequent delivery.

CONCLUSION

Previous uneventful delivery of a macrosomic neonate to a non-diabetic mother should not be regarded as a risk factor for SD in the subsequent delivery.

Previous non-diabetic pregnancy with a macrosomic infant - Is it a risk factor for subsequent gestational diabetes mellitus?

AIM

To examine the association between previous pregnancy neonatal birthweight (BW) among non-diabetic women and the rate of gestational diabetes mellitus (GDM) in the subsequent pregnancy.

METHODS

Case control study in a university affiliated medical center from 2005 to 2019. Women who had a singleton pregnancy and two consecutive deliveries in our medical center were included. GDM diagnosis was based on either National Diabetes Data Group or Carpenter and Coustan criteria. Univariate analysis was followed by multivariate logistic regression.

RESULTS

A total of 47,823 women were included. GDM incidence among the subsequent pregnancies was 2.7% (1,312 women). Parturients with GDM had higher mean birthweight in their previous pregnancy compared with parturients without GDM (3336.9 ± 587.4 vs 3229.9 ± 488.2 g, p < 0.001). Women with GDM in the subsequent pregnancy as compared to women without GDM showed higher rates of having previous big neonates: BW ≥ 90% for gestational age, BW ≥ 4000 gr and BW ≥ 4500 g (p < 0.01 for all), 20.2% vs. 10.7%, 9.6% vs 4.5% and 1% vs. 0.3% respectively. Multivariate analysis adjusted for known risk factors for GDM showed that these factors were still independently associated with occurrence of GDM in the subsequent pregnancy 1.7 (1.1-2.5), 1.9 (1.1-3.4), 6.0 (1.6-22.8), respectively.

CONCLUSION

Neonatal BWs in previous pregnancy is associated with increased GDM incidence in the subsequent pregnancy; Women with previous macrosomia should possibly undergo a diagnostic testing.

Screening for gestational diabetes mellitus - Can we use the 50-g glucose challenge test of the previous pregnancy?

AIM

To assess the association between previous pregnancy glucose challenge test (GCT) result among non-diabetic women and the rate for gestational diabetes mellitus (GDM) in the subsequentpregnancy.

METHODS

Retrospective database study in a university affiliated medical center from 2005 to 2017. Women who had a singleton pregnancy and two consecutive deliveries in our medical center were included. GDM diagnosis was based on either National Diabetes Data Group or Carpenter and Coustan criteria. Univariate analysis was followed by multivariate logistic regression.

RESULTS

A total of 31,861 women were included. GDM incidence among the subsequent pregnancies was 2.1% (670 women). Parturients with GDM had higher mean GCT results in their previous pregnancy compared with parturients without GDM (127.5 ± 28 VS. 98.7 ± 24 mg/dl, p < 0.001). Women with GDMA2 had higher former GCT results than women with GDMA1 (135.9 ± 28 VS. 125.7 ± 27 mg/dl, p < 0.001). Positive association between GCT results in previous pregnancy and rates of GDM in the subsequent pregnancy was noted. Using a GCT value of 107 mg/dl (65th percentile), the area under the receiver-operating curve was 0.79.

CONCLUSION

GCT results in previous pregnancy is associated with GDM incidence in the subsequent pregnancy. Future prospective studies are warranted to better delineate the best screening approach for this subset of patients.

Universal early pregnancy glycosylated hemoglobin A1c as an adjunct to Carpenter-Coustan screening: an observational cohort study

BACKGROUND

Early pregnancy screening for preexisting and gestational diabetes mellitus is widely recommended, but the details of screening (eg, targeted vs universal screening, criteria to identify women requiring early screening, specific screening strategy) remain controversial and poorly defined.

OBJECTIVE

The objective of the study was to determine the utility of universal early glycosylated hemoglobin A1c obtained at the first prenatal visit in diagnosing preexisting diabetes and high-risk gestational diabetes mellitus (early glycosylated hemoglobin A1c, 5.9-6.4%). We further sought to determine whether early glycosylated hemoglobin A1c could replace routine Carpenter-Coustan testing and to determine the correlation between early glycosylated hemoglobin A1c and maternal and neonatal morbidity and mortality.

STUDY DESIGN

This was an observational cohort study of women delivering from May 2016 to July 2017 (14 months) at a single county teaching hospital. Multiple gestations and second deliveries during the study interval were excluded. Women with an early glycosylated hemoglobin A1c of ≥ 6.5% were diagnosed with preexisting diabetes. Women with early glycosylated hemoglobin A1c of 5.9-6.4% underwent immediate 3 hour glucose tolerance testing, which if abnormal diagnosed gestational diabetes mellitus and if normal was repeated at 24-28 weeks. Women with early glycosylated hemoglobin A1c <5.9% underwent routine Carpenter-Coustan screening at 24-28 weeks. Receiver-operator curve methodology was used to evaluate the diagnostic properties of early glycosylated hemoglobin A1c for gestational diabetes mellitus. The correlation between early glycosylated hemoglobin A1c and composite measures of maternal and neonatal morbidity and mortality were calculated.

RESULTS

A total of 4144 deliveries remained after exclusions. Median gestational age at early glycosylated hemoglobin A1c draw was 9 weeks (interquartile range, 7-12). Early glycosylated hemoglobin A1c diagnosed 26 women with preexisting diabetes (0.8% of all patients, 37.7% of all preexisting diabetes). A total of 41.9% of 93 women with early glycosylated hemoglobin A1c of 5.9-6.4% had an early diagnosis of gestational diabetes mellitus, accounting for 25.8% of total gestational diabetes mellitus cases. Based on receiver-operator curve analysis, no early glycosylated hemoglobin A1c cutoff had sufficient sensitivity and positive predictive value to diagnose gestational diabetes mellitus. An early glycosylated hemoglobin A1c ≤5.0% (29.2% of patients) had a 98% negative predictive value for gestational diabetes mellitus, suggesting women with an early glycosylated hemoglobin A1c ≤5.0% in a similar-risk population could potentially forego further testing. The per-patient incremental cost for the glycosylated hemoglobin A1c was $3.72.

CONCLUSION

Early glycosylated hemoglobin A1c correlates with maternal and neonatal morbidity and mortality but cannot entirely replace routine Carpenter-Coustan testing because of poor sensitivity. Rather, its use as an adjunct to Carpenter-Coustan testing, with reflex to early 3 hour glucose tolerance testing for those with values 5.9-6.4%, is an inexpensive and simple method that identifies women with preexisting diabetes and high-risk gestational diabetes mellitus early in pregnancy, allowing early intervention and the prospect of improved outcomes.

Gestational Diabetes: Underpinning Principles, Surveillance, and Management

Gestational diabetes mellitus (GDM) is carbohydrate intolerance resulting in hyperglycemia with onset during pregnancy. The article aims to provide clinicians with a working framework to minimize maternal and neonatal morbidity. Landmark historical and recent data are reviewed and presented to provide clinicians with a quick, easy reference for recognition and management of GDM. Data presented tie in insights with underlying pathophysiologic processes leading to GDM. Screening and diagnostic thresholds are discussed along with management upon diagnosis. Good clinical practice regarding screening, diagnosis, and management of GDM effectively reduces risk and improves outcomes of women and fetuses in affected pregnancies.