Practice Bulletin No. 180: Gestational Diabetes Mellitus

What is known and what remains unresolved regarding gestational diabetes mellitus (GDM)

Gestational diabetes mellitus (GDM) has become a major public health issue and one of the most discussed topics in contemporary obstetrics. Due to rising prevalence of GDM worldwide impact and importance of this medical condition in good quality antenatal care is growing. GDM is associated with serious adverse perinatal outcomes and unfavorable long-term health consequences for both, mother and her child. Despite a great amount of knowledge accumulated regarding GDM, medical community remains indecisive and still debates the most appropriate diagnostic strategy, screening policy, and treatment options for pregnancies complicated with GDM. These unresolved issues generate controversies, motivate further research and contribute to the growing interest surrounding GDM. In this review we will discuss and try to explain some of them.

Celiac Disease and Pregnancy Outcomes in Patients with Gestational Diabetes Mellitus

AIM

Gestational diabetes mellitus (GDM) and celiac disease, if not diagnosed and properly treated, are associated with adverse outcomes of pregnancy. The aim of our study was to examine pregnancies complicated by GDM in celiac and nonceliac women in terms of their metabolic parameters and maternal and fetal outcomes.

METHODS

The study involved 60 women with GDM, 20 with and 40 without celiac disease. Maternal clinical and metabolic parameters (glucose and insulin levels in the oral glucose tolerance test (OGTT), fasting plasma glucose, HbA1c, lipid profile, prepregnancy BMI, gestational weight gain, and chronic diseases), pregnancy outcomes (gestational hypertension, pre-eclampsia, eclampsia, time, and mode of delivery), and fetal parameters (weight and length at birth, and neonatal complications) were recorded.

RESULTS

The two groups did not differ significantly in maternal parameters other than blood glucose levels at 120' in the diagnostic OGTT (141.2 ± 35.2 vs 161.2 ± 35.4, mg/dl, p=0.047), prepartum cLDL (127.2 ± 43.5 vs 179.6 ± 31.7 mg/dl, p ≤ 0.001), and total cholesterol (229.0 ± 45.9 vs 292.5 ± 42.1 mg/dl, p ≤ 0.001), which were significantly lower in celiac women than in nonceliac controls. Children born from celiac women had a significantly higher birth weight (3458.1 ± 409.8 vs 3209.0 ± 432.7 g, p=0.044) and ponderal index (2.89 ± 0.32 vs 2.66 ± 0.25 g/cm3, p=0.006) and were more likely to be large for gestational age (27.8% vs 2.5%, p=0.012). Analyzing the composition of the celiac and nonceliac women's diet showed that, for the same amount of kilocalories, the gluten-free diet was associated with a slight increase in the amount of carbohydrates (49.75% vs 48.54%) and a reduction in the amount of protein (21.10% vs 23.31%) and especially of fiber (9.84% vs 12.71%).

CONCLUSIONS

Celiac women with GDM have much the same pregnancy outcomes as nonceliac women with GDM, except for fetal overgrowth. Gluten-free food, being richer in carbohydrates and less rich in fiber and protein, could have a role in fetal growth in celiac women.

One elevated oral glucose tolerance test value in pregnancy increases the risk for future diabetes mellitus type 2

PURPOSE

Women with only one elevated 100 g OGTT value are not considered as having gestational diabetes mellitus (GDM) and therefore there are no recommendations to address this population as a risk group for type 2 diabetes mellitus (T2DM). We aimed to elucidate whether one elevated OGTT value increases the risk for T2DM.

METHODS

A retrospective population-based cohort study of women with a first diagnosis of GDM who delivered between 1991 and 2011 was conducted. Women were divided according to GDM diagnosis criteria into three groups: (1) at least two elevated values of Carpenter and Coustan criteria (C&C; N = 209), (2) At least two elevated values of the National Diabetes Data Group (NDDG) criteria (NDDG2; N = 290) and (3) only one elevated value of the NDDG criteria (NDDG1; N = 226). A fourth group comprising women without GDM was included (control; N = 352). The primary outcome was the development of T2DM.

RESULTS

The mean follow-up was 12.4 ± 5.3 years and the mean age at follow-up was 43.0 ± 5.7 years. The rate of T2DM in the control, C&C, NDDG1 and NDDG2 groups were 5%, 18%, 19% and 31%, respectively. All GDM diagnoses were independent risk factors for T2DM in multivariable Cox regression when compared to controls, adjusted hazard ratio and 95% CI: C&C 7.8 [95% CI 3.7-16.4], NDDG1 5.5 [2.6-11.6], and NDDG2 10.5 [5.2-21.4]. Additional independent risk factors were parity, fasting and 1-h post-glucose load of the OGTT and insulin use.

CONCLUSIONS

Women with one elevated OGTT value using the NDDG criteria are at increased risk for T2DM. Further studies are needed to decide whether those women should be considered a focus group for long-term surveillance and T2DM prevention interventions.

A Comparison of Predictive Performances between Old versus New Criteria in a Risk-Based Screening Strategy for Gestational Diabetes Mellitus

Background

The definition of the high-risk group for gestational diabetes mellitus (GDM) defined by the American College of Obstetricians and Gynecologists was changed from the criteria composed of five historic/demographic factors (old criteria) to the criteria consisting of 11 factors (new criteria) in 2017. To compare the predictive performances between these two sets of criteria.

Methods

This is a secondary analysis of a large prospective cohort study of non-diabetic Korean women with singleton pregnancies designed to examine the risk of GDM in women with nonalcoholic fatty liver disease. Maternal fasting blood was taken at 10 to 14 weeks of gestation and measured for glucose and lipid parameters. GDM was diagnosed by the two-step approach.

Results

Among 820 women, 42 (5.1%) were diagnosed with GDM. Using the old criteria, 29.8% (n=244) of women would have been identified as high risk versus 16.0% (n=131) using the new criteria. Of the 42 women who developed GDM, 45.2% (n=19) would have been mislabeled as not high risk by the old criteria versus 50.0% (n=21) using the new criteria (1-sensitivity, 45.2% vs. 50.0%, P>0.05). Among the 778 patients who did not develop GDM, 28.4% (n=221) would have been identified as high risk using the old criteria versus 14.1% (n=110) using the new criteria (1-specificity, 28.4% vs. 14.1%, P<0.001).

Conclusion

Compared with the old criteria, use of the new criteria would have decreased the number of patients identified as high risk and thus requiring early GDM screening by half (from 244 [29.8%] to 131 [16.0%]).

Materno-Fetal and Neonatal Complications of Diabetes in Pregnancy: A Retrospective Study

The aim of this case-control study was to evaluate maternal-fetal and neonatal clinical outcomes in a group of patients with gestational diabetes mellitus (GDM) and pregestational diabetes such as diabetes mellitus type 1 (DM1) and diabetes mellitus type 2 (DM2) and compare them with those of patients without diabetes. A total of 414 pregnant women, nulliparous and multiparous, with single pregnancy were recruited. The selected patients were divided into two groups. Among 207 patients (group cases), 183 had GDM and 24 pregestational diabetes (of which n = 17 diagnosed with DM1 and n = 7 with diagnosis of DM2). Two-hundred-seven patients with a negative pathologic history of GDM, DM1 and DM2 represented the population of controls (group control). We reported an incidence of preterm delivery of 23.2% in the group of cases, of 18.3% in the group of patients with GDM and 66.7% in the group of patients DM1/2. Fetal growth disorders, such as intrauterine growth retardation (IUGR), small for gestational age (SGA), fetal macrosomia, were detected in four fetuses out of 207 (1.93%) in the control group and 20 fetuses out of 207 in the case group (9.67%, p-value 0.001); of these 16 of 183 fetuses of the GDM group (8.74%, p-value 0.002) and 4 of 24 fetuses of the DM1/2 group (16.67%, p-value 0.005). A very strong correlation between diabetes mellitus type 1 and preeclampsia (p-value < 0.0001) was observed. Close monitoring of pregnant women with diabetes is recommended to prevent maternal-fetal and neonatal complications.

A review of gestational diabetes mellitus management, risk factors, maternal and neonatal outcomes in two major maternity hospitals in the United Arab Emirates: A report from Dubai

OBJECTIVES

This study was conducted in order to explore and analyze the status of gestational diabetes (GDM) amongst pregnant women in Dubai, United Arab Emirates (UAE); a country with high prevalence of diabetes. We aimed to describe GDM-associated risk factors and clinical outcomes of pregnant women and their neonates. Our objective was to contribute to the broader literature on reproductive health disparities and to inform efforts to improve GDM care at our region.

METHODS

Chart review of case records were used to collect data on both maternal and neonatal parameters and outcomes during the specified study period from two main maternity hospitals in Dubai.

RESULTS

UAE national women with GDM were more prone to be obese or overweight compared to non-UAE women (p < 0.0001, and p < 0.0001 respectively). In addition, UAE national women with GDM had higher history of GDM in previous pregnancies (p < 0.0001) and more family history of diabetes (p < 0.0001).The neonate admission into NICU was significantly associated with cesarean section (p < 0.0001), twins (p < 0.0001), preeclampsia (p = 0.02), receiving MgSO4 (p = 0.02), birth weight less than 2500 g (p < 0.0001), low Apgar scores (p < 0.0001), baby with congenital anomaly (p < 0.0001), and neonatal hypoglycemia (p < 0.0001).

CONCLUSIONS

Our results demonstrate that pregnant women with GDM who are UAE nationals and have higher parity need to be under special attention during their pregnancy in order to improve both maternal and neonatal outcomes.

The effect of group prenatal care for women with diabetes on social support and depressive symptoms: a pilot randomized trial

Objective: To measure the impact of group prenatal care (GPC) on diabetes-specific peer support and depressive symptoms in women with pregnancies complicated by diabetes.Materials and methods: This is a planned secondary analysis of a two-center pilot randomized controlled trial conducted at Denver health (DH) and Washington University in St. Louis (WU) including Spanish (DH) or English (WU) speaking women with type 2 or gestational diabetes. Women were randomized to diabetes GPC or individual prenatal care (IPC) in the resident diabetes clinic. Participants completed an Edinburgh Postnatal Depression Scale (EPDS) at randomization, at 38-week gestation and at 6-12 weeks postpartum. The diabetes support scale (DSS), which includes 12 questions answered on a Likert scale, was administered at 38 weeks. Analysis was by intention to treat (clincaltrials.gov#NCT02444325).Results: A total of 84 women were consented and randomized. Six withdrew consent (two from each cohort) or were lost to follow-up (two from IPC), and three did not complete the 38-week assessment (two from GPC and one from IPC), resulting in primary outcome data available for 75 women: 38 in GPC and 37 in IPC. More women randomized to GPC reported composite positive peer support on the DSS (52.5 versus 26.3%; p < .02). There were no differences in EPDS scores, depression (EPDS >10), or rates of improved EPDS score from baseline to 38 weeks.Conclusion: GPC for women with diabetes is associated with improved diabetes-specific peer social support with no significant impact on depressive symptoms.Clinical trial registration: Clincaltrials.gov NCT02444.

Comparative impact of pharmacological treatments for gestational diabetes on neonatal anthropometry independent of maternal glycaemic control: A systematic review and meta-analysis

BACKGROUND

Fetal growth in gestational diabetes mellitus (GDM) is directly linked to maternal glycaemic control; however, this relationship may be altered by oral anti-hyperglycaemic agents. Unlike insulin, such drugs cross the placenta and may thus have independent effects on fetal or placental tissues. We investigated the association between GDM treatment and fetal, neonatal, and childhood growth.

METHODS AND FINDINGS

PubMed, Ovid Embase, Medline, Web of Science, ClinicalTrials.gov, and Cochrane databases were systematically searched (inception to 12 February 2020). Outcomes of GDM-affected pregnancies randomised to treatment with metformin, glyburide, or insulin were included. Studies including preexisting diabetes or nondiabetic women were excluded. Two reviewers independently assessed eligibility and risk of bias, with conflicts resolved by a third reviewer. Maternal outcome measures were glycaemic control, weight gain, and treatment failure. Offspring anthropometric parameters included fetal, neonatal, and childhood weight and body composition data. Thirty-three studies (n = 4,944), from geographical locations including Europe, North Africa, the Middle East, Asia, Australia/New Zealand, and the United States/Latin America, met eligibility criteria. Twenty-two studies (n = 2,801) randomised women to metformin versus insulin, 8 studies (n = 1,722) to glyburide versus insulin, and 3 studies (n = 421) to metformin versus glyburide. Eleven studies (n = 2,204) reported maternal outcomes. No differences in fasting blood glucose (FBS), random blood glucose (RBS), or glycated haemoglobin (HbA1c) were reported. No studies reported fetal growth parameters. Thirty-three studies (n = 4,733) reported birth weight. Glyburide-exposed neonates were heavier at birth (58.20 g, 95% confidence interval [CI] 10.10-106.31, p = 0.02) with increased risk of macrosomia (odds ratio [OR] 1.38, 95% CI 1.01-1.89, p = 0.04) versus neonates of insulin-treated mothers. Metformin-exposed neonates were born lighter (-73.92 g, 95% CI -114.79 to -33.06 g, p < 0.001) with reduced risk of macrosomia (OR 0.60, 95% CI 0.45-0.79, p < 0.001) than insulin-exposed neonates. Metformin-exposed neonates were born lighter (-191.73 g, 95% CI -288.01 to -94.74, p < 0.001) with a nonsignificant reduction in macrosomia risk (OR 0.32, 95% CI 0.08-1.19, I2 = 0%, p = 0.09) versus glyburide-exposed neonates. Glyburide-exposed neonates had a nonsignificant increase in total fat mass (103.2 g, 95% CI -3.91 to 210.31, p = 0.06) and increased abdominal (0.90 cm, 95% CI 0.03-1.77, p = 0.04) and chest circumferences (0.80 cm, 95% CI 0.07-1.53, p = 0.03) versus insulin-exposed neonates. Metformin-exposed neonates had decreased ponderal index (-0.13 kg/m3, 95% CI -0.26 to -0.00, p = 0.04) and reduced head (-0.21, 95% CI -0.39 to -0.03, p = 0.03) and chest circumferences (-0.34 cm, 95% CI -0.62 to -0.05, p = 0.02) versus the insulin-treated group. Metformin-exposed neonates had decreased ponderal index (-0.09 kg/m3, 95% CI -0.17 to -0.01, p = 0.03) versus glyburide-exposed neonates. Study limitations include heterogeneity in dosing, heterogeneity in GDM diagnostic criteria, and few studies reporting longitudinal growth outcomes.

CONCLUSIONS

Maternal randomisation to glyburide resulted in heavier neonates with a propensity to increased adiposity versus insulin- or metformin-exposed groups. Metformin-exposed neonates were lighter with reduced lean mass versus insulin- or glyburide-exposed groups, independent of maternal glycaemic control. Oral anti-hyperglycaemics cross the placenta, so effects on fetal anthropometry could result from direct actions on the fetus and/or placenta. We highlight a need for further studies examining the effects of intrauterine exposure to antidiabetic agents on longitudinal growth, and the importance of monitoring fetal growth and maternal glycaemic control when treating GDM. This review protocol was registered with PROSPERO (CRD42019134664/CRD42018117503).

Markers for undiagnosed type 2 diabetes mellitus during pregnancy-A population-based retrospective cohort study

BACKGROUND

To examine possible markers for undiagnosed type 2 diabetes in early-onset gestational diabetes mellitus (GDM).

METHODS

A population-based retrospective cohort study of women with GDM diagnosed prior to the 24th week, who delivered between 2005 and 2018, was conducted. The results of the 50-g glucose challenge test, 100-g oral glucose tolerance test, and the first available glycosylated hemoglobin (HbA1c) were examined as markers for type 2 diabetes diagnosed 6 to 12 weeks post pregnancy, which is suggestive of pregestational diabetes. This was done by calculating the area under the curve (AUC) of the receiver operating characteristic (ROC) curve for each marker. These markers and additional ones were evaluated for independency by stepwise multivariate logistic regression.

RESULTS

Of 69 417 pregnancies, 3321 (5%) pregnancies were with GDM. Of them, in 261 (8%) women GDM was diagnosed prior to the 24th week, and 219 (84%) women had available data for analysis. Among them, 11 (5%) women had type 2 diabetes post pregnancy. Elevated HbA1c was the most accurate marker for undiagnosed type 2 diabetes (AUC 91% with 95% CI [81%-100%]) and the only independent marker for undiagnosed type 2 diabetes in multivariate analysis (odds ratio [OR] 19; 95% CI [3.2-109], C statistic = 88%). Using the ROC curve, a cutoff of 5.8% predicted type 2 diabetes with 89% sensitivity, 86% specificity, 99.4% negative predictive value, and 23% positive predictive value.

CONCLUSIONS

Early-onset GDM with HbA1c ≥ 5.8% should be managed as type 2 diabetes. Definitive diagnosis should be done after delivery.

Maternal serum pentraxin 3 level in early pregnancy for prediction of gestational diabetes mellitus

Background

Our study aimed to reveal the relationship of maternal pentraxin 3 (PTX3)'s serum concentrations in early pregnancy with gestational diabetes mellitus (GDM) and to explore its potential in the prediction of GDM.

Methods

Totally 824 pregnant women were enrolled and divided into a GDM group and a normal glucose tolerance (NGT) group, whose maternal fasting serum PTX3 levels, plasma glucose and insulin were collected. The beta cell function index and quantitative insulin sensitivity check index (QUICKI) was calculated and a homeostatic model assessment of insulin resistance (HOMA-IR) was used with SPSS 22 software used for statistical analysis.

Results

Of all subjects, 13.59% developed GDM. Compared to the NGT group, the PTX3 level was increased in the GDM group (1.48 vs. 1.52 ng/mL, P<0.05), and independently associated with the prediction of GDM (4.209, 95% CI, 1.756-10.091) (P=0.001). The area under receiver operating characteristic curve (AUROC) of the combined screening of PTX3 for GDM was incremented to 0.657 by the addition of maternal characteristics, and it reached a maximum of 0.743 in further combination with biochemical markers.

Conclusions

Serum PTX3 levels in early pregnancy may provide a useful approach for early prediction of GDM.

Longitudinal changes in glucose metabolism in women with gestational diabetes, from late pregnancy to the postpartum period

AIMS/HYPOTHESIS

This study aimed to determine, in women with gestational diabetes (GDM), the changes in insulin sensitivity (Matsuda Insulin Sensitivity Index; IS_OGTT), insulin response and disposition index (DI) from late pregnancy (34-37 weeks gestation, T1), to early postpartum (1-5 days, T2) and late postpartum (6-12 weeks, T3). A secondary aim was to correlate the longitudinal changes in maternal lipids, adipokines, cytokines and weight in relation to the changes in IS_OGTT, insulin response and DI.

METHODS

IS_OGTT, insulin response and DI were calculated at the three time points (T1, T2 and T3) using the results of a 75 g OGTT. Adipokines, cytokines and lipids were measured prior to each OGTT. Linear mixed-effects models were used to compare changes across each time point. Changes in IS_OGTT, insulin response and DI were correlated with changes in maternal adipokines, cytokines and lipids at each time point.

RESULTS

A total of 27 women completed all assessments. Compared with T1, IS_OGTT was 11.20 (95% CI 8.09, 14.31) units higher at 1-5 days postpartum (p < 0.001) and was 5.49 (95% CI 2.38, 8.60) units higher at 6-12 weeks postpartum (p < 0.001). Compared with T1, insulin response values were 699.6 (95% CI 957.5, 441.6) units lower at T2 (p < 0.001) and were 356.3 (95% CI 614.3, 98.3) units lower at T3 (p = 0.004). Compared with T1, the DI was 6434.1 (95% CI 2486.2, 10,381.0) units higher at T2 (p = 0.001) and was 4262.0 (95% CI 314.6, 8209.3) units higher at T3 (p = 0.03). There was a decrease in mean cholesterol, triacylglycerol, LDL-cholesterol and VLDL-cholesterol from T1 to T2 (all p < 0.001), and an increase in mean C-reactive protein, IL-6 and IL-8 from T1 to T2 (all p < 0.001). Mean leptin decreased from T1 to T2 (p = 0.001). There was no significant change in mean adiponectin (p = 0.99) or TNF-α (p = 0.81) from T1 to T2. The mean maternal BMI decreased from T1 to T2 (p = 0.001) and T3 (p < 0.001). There were no significant correlations between any measure of change in IS_OGTT, insulin response and DI and change in maternal cytokines, adipokines, lipids or weight from T1 to T2.

CONCLUSIONS/INTERPRETATION

In women with GDM, delivery was associated with improvement in both insulin sensitivity and insulin production within the first few days. Improvement in insulin production persisted for 6-12 weeks, but insulin sensitivity deteriorated slightly. These changes in glucose metabolism were not associated to changes in lipids, leptin, inflammation markers or body weight.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02082301.

The association of pregestational and gestational diabetes with severe neonatal morbidity and mortality

OBJECTIVE

To estimate the association between maternal diabetes and severe neonatal morbidity.

STUDY DESIGN

Retrospective cohort study of nonanomalous neonates born 24⁰-41⁶ weeks' gestation from two large multisite U.S. cohorts, Cesarean Registry and Consortium on Safe Labor. The exposure was pregestational versus gestational versus no diabetes. The composite neonatal outcome included respiratory distress syndrome, mechanical ventilation, necrotizing enterocolitis, grade 3-4 intraventricular hemorrhage, and death. Multivariable logistic regression estimated the association between diabetes and neonatal morbidity.

RESULT

Of 196,006 eligible neonates, 2993 (1.5%) were born to mothers with pregestational diabetes and 10,549 (5.4%) with gestational diabetes. Pregestational diabetes was associated with higher odds of neonatal morbidity versus gestational diabetes (aOR 2.27, 95% CI 1.95-2.64), as well as no diabetes (aOR 1.96, 95% CI 1.63-2.35). Gestational diabetes was associated with higher odds of neonatal morbidity versus no diabetes (aOR 1.16, 95% CI 1.04-1.30).

CONCLUSION

Pregestational and gestational diabetes are risk factors for severe neonatal morbidity.

Adherence to postpartum diabetes mellitus screening, do associated pregnancy complications make a difference?

AIMS

We aimed to investigate the impact of Gestational Diabetes Mellitus (GDM) complications on compliance with postpartum Diabetes screening.

METHODS

A retrospective cohort study was conducted comparing screening rates of women with and without GDM associated complications who delivered at the Soroka University Medical Center, between 2016 and 2017. The screening test of choice was a 2-hour 75 g oral glucose tolerance test, taken 6-12 weeks after delivery. GDM associated complications included one or more of the following: polyhydramnios, macrosomia, shoulder dystocia or cesarean section. Univariate analysis was used in order to examine if GDM associated complications were associated with postpartum diabetes screening.

RESULTS

During the study period a 164 women were included, of which, 82 women had suffered from GDM associated complications and comprised the study group and 82 women with GDM but without complications comprised the comparison group. Women in the study group were significantly older with a higher parity order. Induction rates were significantly higher among the comparison group, whereas, cesarean section rates were higher among the study group. No difference was noted with regard to neonatal outcomes. Women in the study group were not found to be more likely to be given screening recommendations at discharge (P = 0.50), at their postpartum visit (P = 0.36) or to perform DM screening postpartum (P = 0.17).

CONCLUSION

Women with GDM associated complications had a higher rate of compliance to postpartum DM screening recommendations. However, in the current study this difference did not reach statistical significance.

Trends in the incidence of fetal macrosomia and its phenotypes in the United States, 1971-2017

PURPOSE

Studies have reported a surge in the prevalence of obesity among various demographic groups including pregnant women in the U.S. Given the association between maternal obesity and risk of fetal macrosomia, we hypothesized that the incidence of fetal macrosomia will be on the rise in the U.S. We examined trends in fetal macrosomia and macrosomia phenotypes in the U.S. among singleton live births within the gestational age of 28-42 weeks inclusive.

METHODS

This was a retrospective cohort study covering the period 1971-2017 using U.S. Natality Data files. We applied Joinpoint regression models to derive the average annual percentage change in the outcome. We measured incidence and trends of fetal macrosomia which was defined as birth weight ≥ 4000 g. We further subdivided macrosomia into its phenotypes as previously recommended: Grade 1 (4000-4499 g), Grade 2 (4500-4999 g) and Grade 3 (≥ 5000 g).

RESULTS

A total of 147,331,305 singleton births over the entire study period of 47 years were analyzed. From a baseline incidence of 8.84%, the rate of fetal macrosomia declined to 8.07% by the end of the study representing a drop of 8.70% in relative terms. The greatest drop was among infants with Grade 3 macrosomia, the most severe and lethal phenotype. The most impactful factors were maternal age and gestational weight gain.

CONCLUSION

This study is the largest population-based study conducted regarding fetal macrosomia. The rate of fetal macrosomia declined over the previous 5 decades with the most substantial drop observed in the phenotype with the worst prognosis.

Diagnostic Strategies for Gestational Diabetes Mellitus: Review of Current Evidence

PURPOSE OF REVIEW

Currently, the diagnosis of gestational diabetes mellitus (GDM) lacks uniformity. Several controversies are still under debate, especially on the method of screening and diagnosis. This review focuses on recent literature and provides current evidence for the screening and diagnosis of GDM.

RECENT FINDINGS

Selective screening would miss a significant number of women with GDM. In contrast, universal screening has been shown to be cost-effective, compared with selective screening, and is recommended by many medical societies. For the diagnostic methods for GDM, most observational cohort studies reported that the one-step method is associated with improved pregnancy outcomes and is cost-saving or cost-effective, compared with the two-step method, although these findings should be confirmed in the upcoming randomized controlled trials which compare the performance of one-step and two-step methods. On the other hand, the methods of early screening or diagnosis of GDM are varied, and current evidence does not justify their use during early pregnancy. In conclusion, current evidence favors universal screening for GDM using the one-step method. Early screening for GDM is not favorably supported by the literature.

Ethnic Enclaves and Pregnancy and Behavior Outcomes Among Asian/Pacific Islanders in the USA

OBJECTIVES

Ethnic enclaves are ethnically, spatially, and socially distinct communities that may promote health through access to culturally appropriate resources and reduced exposure to discrimination. This study examined ethnic enclave residence and pregnancy outcomes among Asian/Pacific Islander (API) women in the USA.

DESIGN

We examined 9206 API births in the Consortium on Safe Labor (2002-2008). Ethnic enclaves were defined as hospital regions with high percentage of API residents (> 4%), high dissimilarity index (> 0.41; distribution of API and white residents within a geographic area), and high isolation index (> 0.03; interaction between API and white residents in an area). Gestational diabetes mellitus (GDM), preterm birth (PTB), small for gestational age (SGA), and smoking and alcohol use during pregnancy were reported in medical records supplemented with ICD-9 codes. Hierarchical logistic regression models estimated associations between ethnic enclaves and pregnancy outcomes, adjusted for maternal factors, area-level poverty, and air pollution.

RESULTS

Women in enclaves had lower odds of GDM (OR 0.61; 95%CI 0.45, 0.82), PTB (OR 0.74; 95%CI 0.56, 0.99), and SGA (OR 0.68; 95%CI 0.52, 0.89) compared with women in non-enclaves. Prenatal smoking and alcohol use appeared less likely in enclaves, but estimates were imprecise. Within enclaves, about 10.5% of homes speak an API language, compared with 6.0% in non-enclaves. The mean percent of foreign-born API populations was 67.4% in enclaves and 68.8% in non-enclaves.

CONCLUSIONS

API women residing in ethnic enclaves had better pregnancy outcomes than API women residing in non-enclave areas. Access to culturally appropriate social supports and resources may be important for health promotion among API populations.

Association of Fast Food and Supermarket Density with Neonatal Outcomes of Pregnancies Affected by Gestational Diabetes

OBJECTIVE

To measure the association of fast food density (FFD) and supermarket density (SD) with adverse neonatal outcomes in pregnancies with gestational diabetes mellitus (GDM).

STUDY DESIGN

This was a retrospective cohort study of women with GDM who delivered at a tertiary care center in a large metropolitan area (1/2010-2/2016). ZIP codes were used to link women with surrounding food environment. FFD and SD were calculated as the number of establishments per 100,000 residents for each ZIP code and classified into quartiles. Quartile 1 represented lowest FFD or SD. Four neonatal outcomes were assessed: large for gestational age (LGA) neonate, shoulder dystocia, neonatal hypoglycemia, and neonatal intensive care unit admission > 3 days. Bivariable and multivariable analyses estimated associations of FFD and SD with outcomes.

RESULTS

A total of 2,373 women met eligibility criteria. Insurance, race/ethnicity, language, and body mass index differed between quartiles, although GDM type did not. High FFD was associated with lower odds of LGA but not with other outcomes. Low SD and FFD:SD ratios were not associated with any outcomes.

CONCLUSION

Among women with GDM, high FFD was associated with some neonatal outcomes, but low SD and FFD:SD ratio was not. Food environment may not be the only social determinant of neonatal outcomes in pregnancies with GDM.

Progression to Gestational Diabetes Mellitus in Pregnant Women with One Abnormal Value in Repeated Oral Glucose Tolerance Tests

BACKGROUND

Women with one abnormal value (OAV) in a 100 g oral glucose tolerance test (OGTT) during pregnancy are reported to have an increased risk of adverse pregnancy outcomes. However, there is limited data about whether women with OAV will progress to gestational diabetes mellitus (GDM) when the OGTT is repeated.

METHODS

To identify clinical and metabolic predictors for GDM in women with OAV, we conducted a retrospective study and identified women with OAV in the OGTT done at 24 to 30 weeks gestational age (GA) and repeated the second OGTT between 32 and 34 weeks of GA.

RESULTS

Among 137 women with OAV in the initial OGTT, 58 (42.3%) had normal, 40 (29.2%) had OAV and 39 (28.5%) had GDM in the second OGTT. Maternal age, prepregnancy body mass index, weight gain from prepregnancy to the second OGTT, GA at the time of the OGTT, and parity were similar among normal, OAV, and GDM groups. Plasma glucose levels in screening tests were different (151.8±15.7, 155.8±14.6, 162.5±20.3 mg/dL, P<0.05), but fasting, 1-, 2-, and 3-hour glucose levels in the initial OGTT were not. Compared to women with screen negative, women with untreated OAV had a higher frequency of macrosomia.

CONCLUSION

We demonstrated that women with OAV in the initial OGTT significantly progressed to GDM in the second OGTT. Clinical parameters predicting progression to GDM were not found. Repeating the OGTT in women with OAV in the initial test may be helpful to detect GDM progression.

Interrupting the Pathway from Gestational Diabetes Mellitus to Type 2 Diabetes: The Role of Primary Care

OBJECTIVE

Our objective was to describe patient-, provider-, and health systems-level factors associated with likelihood of obtaining guideline-recommended follow-up to prevent or mitigate early-onset type 2 diabetes after a birth complicated by gestational diabetes mellitus (GDM).

METHODS

This study presents a retrospective cohort analysis of de-identified demographic and health care system characteristics, and clinical claims data for 12,622 women with GDM who were continuously enrolled in a large, national U.S. health plan from January 31, 2006, to September 30, 2012. Data were obtained from the OptumLabs Data Warehouse. We extracted 1) known predictors of follow-up (age, race, education, comorbidities, GDM severity); 2) novel factors that had potential as predictors (prepregnancy use of preventive measures and primary care, delivery hospital size); and 3) outcome variables (glucose testing within 1 and 3 years and primary care visit within 3 years after delivery).

RESULTS

Asian ethnicity, higher education, GDM severity, and delivery in a larger hospital predicted greater likelihood of post-GDM follow-up. Women with a prepregnancy primary care visit of any type were two to three times more likely to receive postpartum glucose testing and primary care at 1 year, and 3.5 times more likely to have obtained testing and primary care at 3 years after delivery.

CONCLUSIONS

A history of use of primary care services before a pregnancy complicated by GDM seems to enhance the likelihood of postdelivery surveillance and preventive care, and thus reduce the risk of undetected early-onset type 2 diabetes. An emphasis on promoting early primary care connections for women in their early reproductive years, in addition to its overall value, is a promising strategy for ensuring follow-up testing and care for women after complicated pregnancies that forewarn risk for later chronic illness. Health systems should focus on models of care that connect primary and reproductive/maternity care before, during, and long after pregnancies occur.

Research Gaps in Gestational Diabetes Mellitus: Executive Summary of a National Institute of Diabetes and Digestive and Kidney Diseases Workshop

The National Institute of Diabetes and Digestive and Kidney Diseases convened a workshop on research gaps in gestational diabetes mellitus (GDM) with a focus on 1) early pregnancy diagnosis and treatment and 2) pharmacologic treatment strategies. This article summarizes the proceedings of the workshop. In early pregnancy, the appropriate diagnostic criteria for the diagnosis of GDM remain poorly defined, and an effect of early diagnosis and treatment on the risk of adverse outcomes has not been demonstrated. Despite many small randomized controlled trials of glucose-lowering medication treatment in GDM, our understanding of medication management of GDM is incomplete as evidenced by discrepancies among professional society treatment guidelines. The comparative effectiveness of insulin, metformin, and glyburide remains uncertain, particularly with respect to long-term outcomes. Additional topics in need of further research identified by workshop participants included phenotypic heterogeneity in GDM and novel and individualized treatment approaches. Further research on these topics is likely to improve our understanding of the pathophysiology and treatment of GDM to improve both short- and long-term outcomes for mothers and their children.

Obstetric management, tests, and technologies that impact childhood development

Childhood brain development begins before birth, and obstetric management, tests, and technologies designed to diagnose and treat fetal conditions can have an impact on development. Preconception counseling for maternal diabetes and hypertension affect the risk of fetal congenital anomalies and growth restriction. Patients with risk factors for pre-existing maternal diabetes are offered early diabetic screening because earlier diagnosis and treatment can decrease the risk of fetal and neonatal complications. Screening for chromosomal abnormalities in the first or second trimester is offered to all females regardless of age. Cell-free fetal DNA screening can be used to test for fetal genetic abnormalities as early as 9 weeks of gestation with results available in 10 days. Ultrasound performed around 20 weeks' gestation can identify the 3% of fetuses that have a major congenital malformation. Fetal magnetic resonance imaging can be used to better assess fetal central nervous system abnormalities when neurosonography is inconclusive. Doppler ultrasound can be used to assess blood flow in the umbilical artery and fetal middle cerebral artery to aid in the management of the growth-restricted fetus. In summary, diagnosis and treatment of maternal and fetal conditions from the preconception period throughout pregnancy are important for optimizing fetal health and provide the best opportunity for optimal child development. WHAT THIS PAPER ADDS: Cell-free fetal DNA screening can identify fetal genetic abnormalities as early as 9 weeks' gestation. Ultrasound performed around 20 weeks' gestation can detect major fetal congenital malformations. Fetal magnetic resonance imaging can aid neurosonography in the assessment of fetal central nervous system abnormalities. Doppler ultrasound to assess fetal blood flow is used to successfully manage the growth-restricted fetus.

Optimal Timing of Prenatal Ultrasound in Predicting Birth Weight in Diabetic Pregnancies

OBJECTIVE

This study sought to determine the optimal timing of ultrasound in the third trimester to predict birth weight accurately in diabetic women with a singleton pregnancy.

METHODS

A retrospective cohort study of all diabetic women with a singleton pregnancy treated in Halifax, Nova Scotia, was performed. Estimated fetal weight was derived from ultrasound measures using the Hadlock2 equation. The Mongelli equation was used to predict birth weight. The association between gestational age at ultrasound and accuracy of predicted birth weight was assessed, with accuracy as a continuous variable representing the difference between predicted and actual birth weight and as a categorical variable (with four gestational age categories) representing whether predicted birth weight was within, over, or under 250 g of actual birth weight RESULTS: The cohort of 943 women comprised 121 (12.8%) with type 1 diabetes, 111 (11.7%) with type 2 diabetes, and 711 (75.4%) with gestational diabetes. Ultrasound scans performed at term were the most accurate in predicting birth weight. At this gestational age, the mean difference between predicted and actual birth weight was -30 g (95% confidence interval -109 to -48). After adjusting for maternal body mass index, age, smoking, type of diabetes, and interval between ultrasound examination and delivery, accuracy improved as gestational age at ultrasound increased (P = 0.005). The odds of underpredicting or overpredicting birth weight were not significantly affected by the timing of the ultrasound examination.

CONCLUSION

Because the predictive accuracy of ultrasound prediction of birth weight improves with gestational age, fetal growth assessment at term is recommended to aid with delivery planning in women with diabetes.

Early Pregnancy Hemoglobin A1C and Pregnancy Outcomes: A Population-Based Study

OBJECTIVE

Women with prediabetes are identified from screening for overt diabetes in early pregnancy, but the clinical significance of prediabetes in pregnancy is unclear. We examined whether prediabetes in early pregnancy was associated with risks of adverse outcomes.

STUDY DESIGN

We conducted a retrospective cohort study of pregnant women enrolled in Kaiser Permanente Washington from 2011 to 2014. Early pregnancy hemoglobin A1C (A1C) values, covariates, and outcomes were ascertained from electronic medical records and state birth certificates. Women with prediabetes (A1C of 5.7-6.4%) were compared with those with normal A1C levels (<5.7%) for risk of gestational diabetes mellitus (GDM) and other outcomes including preeclampsia, primary cesarean delivery, induction of labor, large/small for gestational age, preterm birth, and macrosomia. We used modified Poisson's regression to calculate adjusted relative risks (RRs) and 95% confidence intervals (CIs).

RESULTS

Of 7,020 women, 239 (3.4%) had prediabetes. GDM developed in 48% of prediabetic women compared with 11% of women with normal A1C levels (adjusted RR: 2.8, 95% CI: 2.4-3.3). Prediabetes was not associated with all other adverse maternal and neonatal outcomes.

CONCLUSION

Prediabetes in early pregnancy is a risk factor for GDM. Future research is needed to elucidate whether early intervention may reduce this risk.

Low-Carbohydrate Diets for Gestational Diabetes

Nutrition therapy provides the foundation for treatment of gestational diabetes (GDM), and has historically been based on restricting carbohydrate (CHO) intake. In this paper, randomized controlled trials (RCTs) are reviewed to assess the effects of both low- and higher CHO nutrition approaches in GDM. The prevailing pattern across the evidence underscores that although CHO restriction improves glycemia at least in the short-term, similar outcomes could be achievable using less restrictive approaches that may not exacerbate IR. The quality of existing studies is limited, in part due to dietary non-adherence and confounding effects of treatment with insulin or oral medication. Recent evidence suggests that modified nutritional manipulation in GDM from usual intake, including but not limited to CHO restriction, improves maternal glucose and lowers infant birthweight. This creates a platform for future studies to further clarify the impact of multiple nutritional patterns in GDM on both maternal and infant outcomes.

Using the Technology Acceptance Model to Develop StartSmart: mHealth for Screening, Brief Intervention, and Referral for Risk and Protective Factors in Pregnancy

INTRODUCTION

Technology decision support with tailored patient education has the potential to improve maternal and child health outcomes. The purpose of this study was to develop StartSmart, a mobile health (mHealth) intervention to support evidence-based prenatal screening, brief intervention, and referral to treatment for risk and protective factors in pregnancy.

METHODS

StartSmart was developed using Davis' Technology Acceptance Model with end users engaged in the technology development from initial concept to clinical testing. The prototype was developed based upon the current guidelines, focus group findings, and consultation with patient and provider experts. The prototype was then alpha tested by clinicians and patients. Clinicians were asked to give feedback on the screening questions, treatment, brief motivational interviewing, referral algorithms, and the individualized education materials. Clinicians were asked about the feasibility of using the materials to provide brief intervention or referral to treatment. Patients were interviewed using the think aloud technique, a cognitive engineering method used to inform the design of mHealth interventions. Interview questions were guided by the Screening, Brief Intervention, Referral to Treatment theory and attention to usefulness and usability.

RESULTS

Expert clinicians provided guidance on the screening instruments, resources, and practice guidelines. Clinicians suggested identifying specific prenatal visits for the screening (first prenatal visit, 28-week visit, and 36-week visit). Patients reported that the tablet-based screening was useful to promote adherence to guidelines and provided suggestions for improvement including more information on the diabetic diet and more resources for diabetes. During alpha testing, participants commented on navigability and usability. Patients reported favorable responses about question wording and ease of use.

DISCUSSION

Clinicians reported the use of mHealth to screen and counsel pregnant patients on risk and protective factors facilitated their ability to provide comprehensive care.

Does serum hemoglobin A1C during early pregnancy predict performance on the 1-hour glucose challenge test?

PURPOSE

To determine the negative and positive predictive values of hemoglobin A1c (HgbA1c) levels in predicting abnormal 1-hour glucose challenge test (GCT) results in pregnancy.

METHODS

This retrospective cohort study consisted of pregnant patients from a private practice obstetrics clinic. The primary exposure was early HgbA1c measurement, and the primary outcome was third trimester 1-hour GCT results above or below 140 mg/dL. We calculated the predictive value of early HgbA1c to identify a 1-hour GCT of ≤140 mg/dL or >140 mg/dL.

RESULTS

Of the 1404 one-hour GCT results, 635 were associated with HgbA1c being measured in a patient on the same day or before the 1-hour GCT. The median interval between the HgbA1c test and the 1-hour GCT was 95 days (IQR 56-122 days). Among women with a hgbA1c less than or equal to 4.9, 5.0 and 5.1, respectively, the probability of their 1 hour GCT being 140 mg/dl or less was 91.3%, 91.0% and 90.1%, respectively (Table 1). Among our study population, 14.5%, 22.8% and 35.0% had an Hgb A1c less than or equal to 4.9, 5.0 and 5.1 respectively. Among women with HgbA1c greater than 6.1, the probability of their 1-hour GCT being greater than 140 mg/dL was 100%. Only 0.3% of our population had HgbA1c greater than 6.1. There was no other cut point for HgbA1c, where the positive predictive value for predicting an abnormal 1-hour GCT was equal to or greater than 90%.

CONCLUSIONS

The greatest value of an early HgbA1C test appears to be that very low values (5.1 or less) can predict a normal 1 h GCT with high probability (at least 90%). However, it has limited ability to predict abnormal 1 h GCT. Overall, an early HgbA1C cannot replace the 1 h GCT based on the current body of evidence.

Predictors of Health-Protective Behavior and Glycemia After Gestational Diabetes, NHANES 2007-2014

Purpose

This study examined weight loss behavior and the prevalence of hyperglycemia unawareness (unknown high blood glucose) after gestational diabetes mellitus (GDM), within a nationally, representative sample. This study also examined social-demographic, psychosocial, provider communication, and health care access/utilization factors as predictors of A1C and health-protective behavior after GDM.

Methods

A secondary analysis of 2007-2014 National Health and Nutrition Examination Surveys (NHANES) data was conducted, including 205 women, aged 20 to 44 years, with a history of GDM, whose last live birth was in the past 10 years, excluding pregnant women and those with diabetes. Weighted bivariate, stepwise linear, and binary logistic regression analyses were conducted to examine correlates of A1C, weight change, weight loss attempt and behavior, diabetes screening, and physical activity.

Results

Hyperglycemia unawareness was associated with increased A1C and weight gain in the past year. Personal weight loss goal and perception of overweight increased the odds of weight loss attempt. Depressive symptoms were associated with weight gain over the past year. A third of the sample failed to have their glucose tested in the past 3 years. Two-thirds were never told about their personal risk for diabetes, but provider communication increased the odds of meeting weekly activity recommendations and glucose screening. Hispanic women and non-Hispanic black women were less likely to have had glucose screening than non-Hispanic white women.

Conclusion

Diabetes educators should address gaps in provider communication, while supporting psychosocial needs and reducing disparities to encourage health-protective behavior after GDM. The American Association of Diabetes Educators, 7 Self-Care Behaviors (AADE-7TM) provides an excellent framework for interventions to support health-protective behavior after GDM.

Diagnostic thresholds for pregnancy hyperglycemia, maternal weight status and the risk of childhood obesity in a diverse Northern California cohort using health care delivery system data

OBJECTIVE

To estimate the risk of childhood obesity associated with the various criteria proposed for diagnosis of gestational diabetes (GDM), and the joint effects with maternal BMI.

METHODS

Cohort study of 46,396 women delivering at the Kaiser Permanente Northern California health care delivery system in 1995-2004 and their offspring, followed through 5-7 years of age. Pregnancy hyperglycemia was categorized according to the screening and oral glucose tolerance test values proposed for the diagnosis of GDM by the International Association of the Diabetes and Pregnancy Study Group (IADPSG), Carpenter Coustan (CC), and the National Diabetes Data Group (NDDG). Childhood obesity was defined by the International Obesity Task Force's age and sex-specific BMI cut-offs. Poisson regression models estimated the risks of childhood obesity associated with each category of pregnancy glycemia compared to normal screening, and the joint effects of maternal BMI category and GDM by the CC and the IADPSG criteria.

RESULTS

Compared with normal screening, increased risks of childhood obesity were observed for abnormal screening [RR (95% CI): 1.30 (1.22, 1.38)], 1+ abnormal values by the IADPSG or CC [1.47 (1.36, 1.59) and 1.48 (1.37, 1.59), respectively], and 2+ values by CC or NDDG [1.52 (1.39, 1.67) and 1.60 (1.43, 1.78), respectively]. Compared to obese women without GDM, obese women with GDM defined by the CC criteria had significantly increased risk of childhood obesity [1.20 (1.07, 1.34)], which was also observed for GDM by the IADSPG [1.18 (1.07, 1.30)], though GDM did not significantly increase the risk of childhood obesity among normal weight or overweight women.

CONCLUSIONS

The risk of childhood obesity starts to increase at levels of pregnancy glycemia below those used to diagnose GDM and the effect of GDM on childhood obesity risk appears more pronounced in women with obesity. Interventions to reduce obesity and pregnancy hyperglycemia are warranted.

Induction of labor versus expectant management for gestational diabetes mellitus at term

PURPOSE

To evaluate whether induction of labor (IOL), as compared with expectant management, in gestational diabetes mellitus (GDM) mothers at term (between 37^0/7 and 40^6/7), decreases caesarean section (CS) rate and the rate of adverse composite neonatal outcomes.

METHODS

A retrospective cohort study, of all women with GDM and a singleton gestation who delivered at term in a single, tertiary, university-affiliated medical center (2007-2014). We compared outcomes of women who underwent IOL at each week of gestation between 37^0/7 and 40^6/7 weeks with women who were managed expectantly. The primary outcome was CS rate.

RESULTS

Overall, 2472 GDM patients included in the study, of which 880 women had IOL. CS rate was not found to be significantly different between the groups at any gestational age. IOL at 37 weeks was associated with adverse composite neonatal outcome (aOR 2.2, 95% CI 1.4-3.6) and NICU admission (aOR 2.5, 95% CI 1.4-4.4). At 38 weeks, with NICU admission (aOR 2.0, 95% CI 1.4-2.9), and at 39 weeks with fracture of the clavicle. In a sub-analysis of nulliparous women, IOL at 37 weeks had higher odds of NICU admission and adverse composite neonatal outcomes, at 38 weeks with CS and at 39 weeks with fracture of the clavicle.

CONCLUSIONS

IOL in GDM mothers at term does not reduce CS rate and may be associated with increased CS rate among nulliparous women at 38 weeks. It is also associated with increased risk for adverse composite neonatal outcome or NICU admission when done prior to 39^0/7 weeks.

Development and validation of a clinical model for preconception and early pregnancy risk prediction of gestational diabetes mellitus in nulliparous women

Implementation of dietary and lifestyle interventions prior to and early in pregnancy in high risk women has been shown to reduce the risk of gestational diabetes mellitus (GDM) development later in pregnancy. Although numerous risk factors for GDM have been identified, the ability to accurately identify women before or early in pregnancy who could benefit most from these interventions remains limited. As nulliparous women are an under-screened population with risk profiles that differ from their multiparous counterparts, development of a prediction model tailored to nulliparous women may facilitate timely preventive intervention and improve maternal and infant outcomes. We aimed to develop and validate a model for preconception and early pregnancy prediction of gestational diabetes mellitus based on clinical risk factors for nulliparous women. A risk prediction model was built within a large California birth cohort including singleton live birth records from 2007-2012. Model accuracy was assessed both internally and externally, within a cohort of women who delivered at University of Iowa Hospitals and Clinics between 2009-2017, using discrimination and calibration. Differences in predictive accuracy of the model were assessed within specific racial/ethnic groups. The prediction model included five risk factors: race/ethnicity, age at delivery, pre-pregnancy body mass index, family history of diabetes, and pre-existing hypertension. The area under the curve (AUC) for the California internal validation cohort was 0.732 (95% confidence interval (CI) 0.728, 0.735), and 0.710 (95% CI 0.672, 0.749) for the Iowa external validation cohort. The model performed particularly well in Hispanic (AUC 0.739) and Black women (AUC 0.719). Our findings suggest that estimation of a woman's risk for GDM through model-based incorporation of risk factors accurately identifies those at high risk (i.e., predicted risk >6%) who could benefit from preventive intervention encouraging prompt incorporation of this tool into preconception and prenatal care.

Association of Long-term Child Growth and Developmental Outcomes With Metformin vs Insulin Treatment for Gestational Diabetes

IMPORTANCE

Metformin is an emerging option for treating gestational diabetes (GDM). However, because metformin crosses the placenta, patients and clinicians are concerned with its long-term effect on child health.

OBJECTIVE

To estimate the association of treating GDM with metformin vs insulin with child growth and development.

DESIGN, SETTING, AND PARTICIPANTS

Population-based cohort study of New Zealand women treated with metformin or insulin for GDM from 2005 to 2012 and their children. This study linked national health care data to create a cohort of mothers and their children, including data from maternity care, pharmaceutical dispensing, hospitalizations, demographic records, and the B4 School Check (B4SC) preschool health assessment. Women treated pharmacologically with metformin or insulin during pregnancy were included. We excluded pregnancies with evidence of diabetes and deliveries prior to 2013. Liveborn infants were linked to their B4SC results. Data were analyzed between January 2017 and May 2018.

EXPOSURES

Pharmacologic treatment for GDM with metformin or insulin, measured using pharmaceutical claims data.

MAIN OUTCOMES AND MEASURES

Child growth (weight and height) and Strengths and Difficulties Questionnaire (SDQ) scores for behavioral development. All outcomes were derived from the B4SC screening program. Linear and log-binomial regression with inverse probability of treatment weighting was used to estimate the association of child growth and psychosocial outcomes with metformin vs insulin treatment for GDM.

RESULTS

In both treatment groups, the mean (SD) maternal age was 32 (5) years. A large proportion of mothers who were treated with insulin identified as New Zealand European (867 [44.9%]) while 576 mothers who were treated with metformin (28.9%) identified as New Zealand European. Approximately one-third of mothers who were treated with metformin (n = 639) identified as Asian. We identified 3928 pregnancies treated with metformin (n = 1996) or insulin (n = 1932). After adjustment, we observed no meaningful difference in weight for height z scores between children exposed to metformin compared with insulin (mean difference, -0.10; 95% CI, -0.20 to 0.01). Risk of being 85th percentile or greater for weight for height was similar between treatment groups (adjusted risk ratio, 0.92; 95% CI, 0.83-1.02). Mean SDQ scores were not meaningfully different between the treatment groups, Children of metformin-treated mothers were not significantly more likely to have parent-reported SDQ scores of 14 or more (adjusted risk ratio, 1.13; 95% CI, 0.88-1.46) than those of insulin-treated mothers.

CONCLUSIONS AND RELEVANCE

Our study compares long-term outcomes among school-aged children following maternal use of metformin vs insulin treatment for GDM. Children of metformin-treated mothers were indistinguishable on growth and developmental assessments from those of insulin-treated mothers. These results will help inform future GDM treatment guidelines.

The Utility of Lower Glycemic Targets for Treating Gestational Diabetes: A Retrospective Study

OBJECTIVE

In vivo study of glucose homeostasis in pregnancy suggests normal glucose levels are lower than current glycemic targets used in gestational diabetes. After the HAPO study results, our institution began using glycemic targets of fasting 85 mg/dL and 2-hour postprandial of 110 mg/dL. We reviewed our results.

METHODS

A retrospective cohort of GDM patients that delivered at KUMC from January 2007 to May 2017 was reviewed. All patients were diagnosed with the 2-step Carpenter-Coustan thresholds. High targets were compared with low targets. The primary outcome investigated was birthweight > 90% (large for gestational age, LGA).

RESULTS

604 patients were studied, and 34% were treated with low glycemic targets. Our unadjusted results showed that the low-target group had a lower incidence of LGA infants (24.0 vs. 31.8%), higher incidence of neonatal hypoglycemia (20.7 vs. 11.6%), and inductions (39.4 vs. 20.5%). After adjustment for demographic variables, only a higher risk of inductions remained (aOR 2.54 (1.44, 4.49)).

CONCLUSION

Lower glycemic targets did not produce large reductions in fetal overgrowth, but they were associated with a higher rate of inductions. As there were no observed differences in maternal or neonatal outcomes otherwise, aiming for lower glycemic targets in GDM is likely not cost-effective.

Gestational diabetes mellitus is associated with adverse outcomes in twin pregnancies

BACKGROUND

Among singleton pregnancies, gestational diabetes mellitus is associated with adverse outcomes. In twin pregnancies, this association may be attenuated, given the higher rate of prematurity and the a priori increased risk of some of these complications.

OBJECTIVE

Our aim was to test the hypothesis that gestational diabetes mellitus is less likely to be associated with adverse pregnancy outcomes in twin compared with singleton gestations.

METHODS

This retrospective cohort study comprised all twin and singleton live births in Ontario, Canada, 2012-2016. Pregnancy outcomes were compared between women with vs without gestational diabetes mellitus, analyzed separately for twin and singleton births. Adjusted risk ratios and 95% confidence intervals were generated using modified Poisson regression, adjusting for maternal age, nulliparity, smoking, race, body mass index, preexisting hypertension, and assisted reproductive technology.

RESULTS

A total of 270,843 women with singleton (n = 266,942) and twin (n = 3901) pregnancies met the inclusion criteria. In both the twin and singleton groups, gestational diabetes mellitus was associated with (adjusted risk ratio, [95% confidence interval]) cesarean delivery (1.11 [1.02-1.21] and 1.20 [1.17-1.23], respectively) and preterm birth at <37^0/7 weeks (1.21 [1.08-1.37] and 1.48 [1.39-1.57]) and at <34^0/7 weeks (1.45 [1.03-2.04] and 1.25 [1.06-1.47]). In singletons, but not twins, gestational diabetes mellitus was associated with gestational hypertension (1.66 [1.55-1.77]) and preeclampsia. With respect to neonatal outcomes, gestational diabetes mellitus was associated with birthweight greater than the 90th percentile in both twins and singletons, with the risk being 2-fold higher in twins (2.53 [1.52-4.23] vs 1.18 [1.13-1.23], respectively, P = .004). Gestational diabetes mellitus was associated with jaundice in both twins (1.56 [1.10-2.21]) and singletons (1.49 [1.37-1.62) but was associated with the following complications only in singletons: neonatal intensive care unit admission (1.44 [1.38-1.50]), respiratory morbidity (1.09 [1.02-1.16]), and neonatal hypoglycemia (3.20 [3.01-3.40]).

CONCLUSION

In contrast to singleton pregnancies, gestational diabetes mellitus in twins was not associated with hypertensive complications and certain neonatal morbidities. Still, the current study highlights that gestational diabetes mellitus is associated with some adverse pregnancy outcomes including accelerated fetal growth also in twin pregnancies.

Prevalence of Gestational Diabetes in South East Nigeria Using the Updated Diagnostic Guidelines

<b><i>Background:</i></b> Controversy still surrounds the choice of screening methods for gestational diabetes mellitus (GDM). Updated guidelines on hyperglycemias in pregnancy, recognizes 2 categories; Diabetes in pregnancy or pre-gestational diabetes and GDM. Early screening and diagnosis of GDM prevents maternal and fetal adverse outcomes. <b><i>Study Objective:</i></b> The aim of the study was to determine the prevalence of GDM and associated risk factors in a population of pregnant women in Enugu, South East Nigeria. <b><i>Materials and Methods:</i></b> The study was cross sectional and descriptive. All pregnant women attending the antenatal clinic were eligible for the study. A risk factor assessment questionnaire was administered. The one step universal screening with 75 g oral glucose tolerance test was used. The results were tabulated and categorized according to the World Health Organization (2013) Diagnostic Criteria. Statistical analysis was by SPSS version 21. <b><i>Result:</i></b> A total of 205 women were initially screened. Risk factors for GDM were identified in up to third of the subjects. They were aged 15–41 years (28.6 ± 4.9 years). OGTT was performed in 142 of the subjects (who came fasting). Gestational age was 8–40 weeks (28.5 ± 7.3); gravidity, 1–9 (2.4 ± 1.5); parity, 0–4 (1.3 ± 1.4); miscarriages, 0–5; and live births, 0–5. Blood glucose levels were 60–145 mg/dL (85.5 ± 12.5) fasting; 77–229 mg/dL (131.8 ± 27.2) at 1 h and 72–223 mg/dL (123.1 ± 25.0) at 2 h post glucose load. The WHO (2013) criteria for GDM were met in 51 subjects (35.9%), WHO 1999 in 29 (20.4%); IAPDSG/American Diabetes Association in 54 (38%); NICE in 44 (31%) and DIPSI in 25 (17.6%). Three subjects had diabetes in pregnancy. Previous miscarriages and macrosomic babies, family history of diabetes mellitus, previous GDM, hypertension and recurrent urinary tract infection were found to be significant risk factors for the development of GDM. <b><i>Conclusion:</i></b> The study highlights the high prevalence of GDM in our local population. At every level, screening and management of GDM should be incorporated as a routine antenatal service.

Frequency of Gestational Diabetes Mellitus Reappearance or Absence during the Second Pregnancy of Women Treated at Mayo Clinic between 2013 and 2018

The Center for Disease Control and Prevention ranks diabetes mellitus (DM) as the seventh leading cause of death in the USA. The most prevalent forms of DM include Type 2 DM, Type 1 DM, and gestational diabetes mellitus (GDM). While the acute problem of diabetic hyperglycemia can be clinically managed through dietary control and lifestyle changes or pharmacological intervention with oral medications or insulin, long-term complications of the disease are associated with significant morbidity and mortality. These long-term complications involve nearly all organ systems of the body and share common pathologies associated with endothelial cell abnormalities. To better understand the molecular mechanisms underlying DM as related to future long-term complications following hyperglycemia, we have undertaken a study to determine the frequency that GDM did or did not occur in the second pregnancy of women who experienced GDM in their first pregnancy between 2013 and 2018 at Mayo Clinic, Rochester, MN. Within the five-year period of the study, the results indicate that 7,330 women received obstetrical care for pregnancy during the study period. Of these, 150 developed GDM in their first pregnancy and of these, 42 (28%) had a second pregnancy. Of these 42 women, 20 again developed GDM and 22 did not develop GDM in their second pregnancy within the study period. Following the occurrence of GDM in the first pregnancy, the study (1) established the number of women with and without GDM in the second pregnancy and (2) confirmed the feasibility to study diabetic metabolic memory using maternal placental tissue from GDM women. These studies represent Phase I of a larger research project whose goal is to analyze epigenetic mechanisms underlying true diabetic metabolic memory using endothelial cells isolated from the maternal placenta of women with and without GDM as described in this article.

Central Obesity Increases the Risk of Gestational Diabetes Partially Through Increasing Insulin Resistance

OBJECTIVE

This study examined the associations of central obesity measures, waist to hip ratio (WHR) and waist circumference (WC), in early pregnancy with subsequent risk of gestational diabetes mellitus (GDM) and evaluated the potential mediating role of insulin resistance markers.

METHODS

Within the prospective Pregnancy Environment and Lifestyle Study cohort of 1,750 women, WC and hip circumference were measured at gestational weeks 10 to 13. In a nested case-control study within the cohort, 115 GDM cases and 230 controls had fasting serum insulin, homeostatic model assessment of insulin resistance (HOMA-IR), and adiponectin measurements at gestational weeks 16 to 19. Poisson and conditional logistic regression models were used, adjusting for established risk factors for GDM, including prepregnancy overweight or obesity.

RESULTS

For women with WHR < 0.85, one or more established risk factors increased GDM risk 1.99-fold (95% CI: 0.99-4.02). For women with WHR ≥ 0.85 but no established risk factors, GDM risk increased 2.41-fold (95% CI: 1.14-5.06), and in those with established risk factors it increased 6.22-fold (95% CI: 3.49-11.10). Similar but attenuated results were observed for WC ≥ 88 cm. Insulin, HOMA-IR, and adiponectin levels mediated the WHR-GDM association by 9% to 11%; corresponding mediation proportions for the WC-GDM association were 35% to 41% (all P  < 0.04).

CONCLUSIONS

Central obesity in early pregnancy represented a high-risk phenotype for GDM independent of other risk factors, including overweight or obesity, and may inform early screening and prevention strategies.

Oxidative Stress as Cause, Consequence, or Biomarker of Altered Female Reproduction and Development in the Space Environment

Oxidative stress has been implicated in the pathophysiology of numerous terrestrial disease processes and associated with morbidity following spaceflight. Furthermore, oxidative stress has long been considered a causative agent in adverse reproductive outcomes. The purpose of this review is to summarize the pathogenesis of oxidative stress caused by cosmic radiation and microgravity, review the relationship between oxidative stress and reproductive outcomes in females, and explore what role spaceflight-induced oxidative damage may have on female reproductive and developmental outcomes.

Pharmacotherapy for hyperglycemia in pregnancy - Do oral agents have a place?

Diabetes is a frequent condition in pregnancy and achieving adequate glycemic control is of paramount importance. Insulin treatment is the gold standard, oral agents are more attractive, but their safety and efficiency should be a prerequisite for their use. We have more information regarding treatment of women with gestational diabetes mellitus where glyburide can induce a picture of fetal hyperinsulinism (higher birthweight and more neonatal hypoglycemia) whereas metformin requires supplemental insulin in a larger proportion of women but achieves satisfactory perinatal outcomes with the exception of preterm birth. Information in patients with Type 2 Diabetes Mellitus is much more limited but also favors metformin. Combinations provide additional possibilities. However, as to long-term outcomes, we have no information on the impact of exposure to glyburide and it is still unclear if in utero exposure to metformin will have any effect on the offspring and the direction of this effect. Women prefer oral agents, indicating the need of additional studies.

Perspectives on diagnostic strategies for hyperglycemia in pregnancy - dealing with the barriers and challenges in China

Hyperglycemia is one of the most common medical conditions women encounter during pregnancy. Hyperglycemia in pregnancy (HIP) is an issue of increasing concern to both obstetricians and administrators and it brings health issues for both mothers and offspring, not only early complications, but also long-term effects. HIP may either have been pre-gestational diabetes mellitus (pGDM), or gestational diabetes mellitus (GDM). After two-child policy fully carried out in China, the incidence of HIP would be increased further. There are many important issues such as the high prevalence of DM misdiagnosis, the diagnostic criteria of GDM, the strategies of GDM management in China need to deal with. We would focus on the barriers and challenges of diagnostic strategies for hyperglycemia in pregnancy in China.

Hepatitis B surface antigen positivity during pregnancy and risk of gestational diabetes mellitus: A systematic review and meta-analysis

Chronic hepatitis B virus (HBV) infection is a prevalent public health issue worldwide. Its impact on important pregnancy outcomes, such as gestational diabetes mellitus (GDM), has not been clearly established. The findings from published studies are inconsistent. In this systematic review and meta-analysis, we aimed to clarify whether HBV infection manifested during pregnancy is associated with an increased risk of GDM. We searched MEDLINE and EMBASE for cohort studies and case-control studies that investigated the association between maternal hepatitis B surface antigen (HBsAg) positivity and GDM. We pooled adjusted odds ratio (aOR) and unadjusted OR, respectively, using the random-effect generic inverse variance method. We assessed risk of bias using the Quality in Prognosis Studies tool and conducted five pre-specified subgroup analyses. In total, 23 cohort studies involving 3 529 223 participants were included. The risk of GDM was 6.48% (1868/28 829) among HBsAg-positive pregnant women and 3.41% (119 283/3 500 394) among HBsAg-negative pregnant women. Meta-analyses of both unadjusted and adjusted effect estimates showed that HBsAg positivity during pregnancy was associated with higher risk of developing GDM (unadjusted OR 1.35, 95% CI: 1.17 to 1.56, I²  = 82.6%; adjusted OR 1.47, 1.22 to 1.76, I²  = 62%). Among pre-specified subgroup analysis, significant differences were found among studies with high vs low or moderate risk of bias. The results were robust to sensitivity analyses. In conclusion, HBsAg positivity during pregnancy has a moderate effect on an increased risk of GDM. Given the size of the population with HBV infection worldwide, however, this effect could have substantial impact on pregnancy. Further studies are warranted to investigate whether active infection with HBeAg positivity would further elevate the risk of adverse events during pregnancy.

Glucose responses to acute and chronic exercise during pregnancy: a systematic review and meta-analysis

Objective

To perform a systematic review and meta-analysis to explore the relationship between prenatal exercise and glycaemic control.

Design

Systematic review with random-effects meta-analysis and meta-regression.

Data sources

Online databases were searched up to 6 January 2017.

Study eligibility criteria

Studies of all designs were included (except case studies and reviews) if they were published in English, Spanish or French, and contained information on the population (pregnant women without contraindication to exercise), intervention (subjective or objective measures of frequency, intensity, duration, volume or type of acute or chronic exercise, alone (‘exercise-only’) or in combination with other intervention components (eg, dietary; ‘exercise+cointervention’) at any stage of pregnancy), comparator (no exercise or different frequency, intensity, duration, volume and type of exercise) and outcome (glycaemic control).

Results

A total of 58 studies (n=8699) were included. There was ‘very low’ quality evidence showing that an acute bout of exercise was associated with a decrease in maternal blood glucose from before to during exercise (6 studies, n=123; mean difference (MD) −0.94 mmol/L, 95% CI −1.18 to −0.70, I2=41%) and following exercise (n=333; MD −0.57 mmol/L, 95% CI −0.72 to −0.41, I2=72%). Subgroup analysis showed that there were larger decreases in blood glucose following acute exercise in women with diabetes (n=26; MD −1.42, 95% CI −1.69 to −1.16, I2=8%) compared with those without diabetes (n=285; MD −0.46, 95% CI −0.60 to −0.32, I2=62%). Finally, chronic exercise-only interventions reduced fasting blood glucose compared with no exercise postintervention in women with diabetes (2 studies, n=70; MD −2.76, 95% CI −3.18 to −2.34, I2=52%; ‘low’ quality of evidence), but not in those without diabetes (9 studies, n=2174; MD −0.05, 95% CI −0.16 to 0.05, I2=79%).

Conclusion

Acute and chronic prenatal exercise reduced maternal circulating blood glucose concentrations, with a larger effect in women with diabetes.

Birthweight thresholds for increased risk for maternal and neonatal morbidity following vaginal delivery: a retrospective study

PURPOSE

To determine neonatal birthweight (BW) thresholds for adverse maternal and neonatal outcome following vaginal delivery.

METHODS

A retrospective cohort study of all women with singleton pregnancies who underwent vaginal delivery in a university-affiliated tertiary hospital (1996-2015). The association between BW and adverse outcome in neonates with BW ≥ 3500 g (> 90th centile BW at 37 weeks' gestation) with 100 g-increment groups was explored. Pregnancies complicated by diabetes mellitus, fetal anomalies or cesarean deliveries were excluded. The composite neonatal outcome was defined as shoulder dystocia or brachial plexus injury. The composite maternal outcome was defined as postpartum hemorrhage or third- or fourth-degree perineal tears.

RESULTS

Of the 121,728 deliveries during the study period, 26,920 (22.1%) met inclusion criteria. Of these, 1024 (3.8%) had a composite adverse maternal outcome and 947 (3.5%) had a composite adverse neonatal outcome. The rates of composite maternal outcomes increased significantly only at a BW of 4800 g and above. The composite neonatal outcomes increased significantly only at a BW of 4400 g and above. In multivariate analysis, after subcategorizing our cohort into 3 BW groups [3500-3999 g (control, n = 23,030); 4000-4399 g (n = 3494); ≥ 4400 g (n = 396)], BW was associated with adverse neonatal outcomes in a dose-dependent manner. In the BW ≥ 4400 g group, to prevent one case of shoulder dystocia or Erb's palsy, 12 cesarean deliveries needed to be performed.

CONCLUSION

For non-diabetic mothers who deliver vaginally, neonatal BW ≥ 4400 g was associated with a significant increase in adverse neonatal outcomes, whereas neonatal BW ≥ 4800 g was associated with a significant increase in adverse maternal outcomes.

Gestational Diabetes Prevalence at Moderate and High Altitude

BACKGROUND

High-altitude (HA) pregnancies have been associated with decreased glucose levels and increased insulin sensitivity versus sea level. Our objective was to determine if the prevalence of gestational diabetes mellitus (GDM) and the impact of demographic characteristics on GDM diagnosis differed at moderate altitude (MA) versus HA.

METHODS

Using a retrospective cohort design, we compared women living at HA (>8250 ft) and MA (4000-7000 ft) during pregnancy. Exclusion criteria were as follows: multiple gestation, preexisting diabetes, unavailable GDM results, or relocation from a different altitude during pregnancy. GDM diagnosis was determined using Carpenter and Coustan criteria. Data were compared by t-test (continuous variables) or chi-squared tests (categorical variables). Univariate, multivariate, and stepwise regression models were used to assess the impact of various factors on GDM prevalence.

RESULTS

There was no difference in GDM prevalence between altitudes in these populations; the relationship between altitude and GDM was nonsignificant in all regression analyses. At MA, maternal age, Hispanic ethnicity, body mass index (BMI), and gestational age (GA) at testing increased GDM incidence in univariate analyses. At HA, maternal age, Hispanic ethnicity, and multiparity increased GDM incidence in univariate analyses.

CONCLUSION

While GDM prevalence did not differ between MA and HA, the impact of maternal demographic characteristics on GDM risk varied by altitude group. Higher BMI and greater GA at testing increased the incidence of GDM at MA, but not at HA. Multiparity had an effect at HA, but not MA. These differences may represent subtle differences in glucose metabolism at HA.

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.

Pregnancy in Women with Obesity

Pregnancy in women with obesity is an important public health problem with short- and long-term implications for maternal and child health. Obesity complicates almost all aspects of pregnancy. Given the growing prevalence of obesity in women, obstetric providers need to understand the risks associated with obesity in pregnancy and the unique aspects of management for women with obesity. Empathic and patient-centered care, along with knowledge, can optimize outcomes for women and children.

Association of Gestational Diabetes With Maternal Disorders of Glucose Metabolism and Childhood Adiposity

IMPORTANCE

The sequelae of gestational diabetes (GD) by contemporary criteria that diagnose approximately twice as many women as previously used criteria are unclear.

OBJECTIVE

To examine associations of GD with maternal glucose metabolism and childhood adiposity 10 to 14 years' postpartum.

DESIGN, SETTING, AND PARTICIPANTS

The Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study established associations of glucose levels during pregnancy with perinatal outcomes and the follow-up study evaluated the long-term outcomes (4697 mothers and 4832 children; study visits occurred between February 13, 2013, and December 13, 2016).

EXPOSURES

Gestational diabetes was defined post hoc using criteria from the International Association of Diabetes and Pregnancy Study Groups consisting of 1 or more of the following 75-g oral glucose tolerance test results (fasting plasma glucose ≥92 mg/dL; 1-hour plasma glucose level ≥180 mg/dL; 2-hour plasma glucose level ≥153 mg/dL).

MAIN OUTCOMES AND MEASURES

Primary maternal outcome: a disorder of glucose metabolism (composite of type 2 diabetes or prediabetes). Primary outcome for children: being overweight or obese; secondary outcomes: obesity, body fat percentage, waist circumference, and sum of skinfolds (>85th percentile for latter 3 outcomes).

RESULTS

The analytic cohort included 4697 mothers (mean [SD] age, 41.7 [5.7] years) and 4832 children (mean [SD] age, 11.4 [1.2] years; 51.0% male). The median duration of follow-up was 11.4 years. The criteria for GD were met by 14.3% (672/4697) of mothers overall and by 14.1% (683/4832) of mothers of participating children. Among mothers with GD, 52.2% (346/663) developed a disorder of glucose metabolism vs 20.1% (791/3946) of mothers without GD (odds ratio [OR], 3.44 [95% CI, 2.85 to 4.14]; risk difference [RD], 25.7% [95% CI, 21.7% to 29.7%]). Among children of mothers with GD, 39.5% (269/681) were overweight or obese and 19.1% (130/681) were obese vs 28.6% (1172/4094) and 9.9% (405/4094), respectively, for children of mothers without GD. Adjusted for maternal body mass index during pregnancy, the OR was 1.21 (95% CI, 1.00 to 1.46) for children who were overweight or obese and the RD was 3.7% (95% CI, -0.16% to 7.5%); the OR was 1.58 (95% CI, 1.24 to 2.01) for children who were obese and the RD was 5.0% (95% CI, 2.0% to 8.0%); the OR was 1.35 (95% CI, 1.08 to 1.68) for body fat percentage and the RD was 4.2% (95% CI, 0.9% to 7.4%); the OR was 1.34 (95% CI, 1.08 to 1.67) for waist circumference and the RD was 4.1% (95% CI, 0.8% to 7.3%); and the OR was 1.57 (95% CI, 1.27 to 1.95) for sum of skinfolds and the RD was 6.5% (95% CI, 3.1% to 9.9%).

CONCLUSIONS AND RELEVANCE

Among women with GD identified by contemporary criteria compared with those without it, GD was significantly associated with a higher maternal risk for a disorder of glucose metabolism during long-term follow-up after pregnancy. Among children of mothers with GD vs those without it, the difference in childhood overweight or obesity defined by body mass index cutoffs was not statistically significant; however, additional measures of childhood adiposity may be relevant in interpreting the study findings.

Optimal Obstetric Management for Women with Diabetes: the Benefits and Costs of Fetal Surveillance

PURPOSE OF REVIEW

To elaborate on the risks and benefits associated with antenatal fetal surveillance for stillbirth prevention in women with diabetes.

RECENT FINDINGS

Women with pregestational diabetes have a 3- to 5-fold increased odds of stillbirth compared to women without diabetes. The stillbirth risk in women with gestational diabetes (GDM) is more controversial; while recent data suggest the odds for stillbirth are approximately 50% higher in women with GDM at term (37 weeks and beyond) than in those without GDM, it is unclear if this risk is seen in women with optimal glycemic control. Current professional society guidelines are broad with respect to fetal testing strategies and delivery timing in women with diabetes. The data supporting strategies to reduce the risk of stillbirth in women with diabetes are limited. Antepartum fetal surveillance should be performed to reduce stillbirth rates; however, the optimal test, frequency of testing, and delivery timing are not yet clear. Future studies of obstetric management for women with diabetes should consider not just individual but also system level costs and benefits associated with antenatal surveillance.