Perinatal outcomes for untreated women with gestational diabetes by IADPSG criteria: a population‐based study

Impact of COVID-19 on gestational diabetes pregnancy outcomes in the UK: A multicentre retrospective cohort study

OBJECTIVE

To determine the impact of implementing emergency care pathway(s) for screening, diagnosing and managing women with gestational diabetes (GDM) during COVID-19.

DESIGN

Retrospective multicentre cohort.

SETTING

Nine National Health Service (NHS) Hospital Trusts/Health boards in England and Scotland.

POPULATION

4915 women with GDM pre-pandemic (1 April 2018 to 31 March 2020), and 3467 women with GDM during the pandemic (1 May 2020 to 31 March 2021).

METHODS

We examined clinical outcomes for women with GDM prior to and during the pandemic following changes in screening methods, diagnostic testing, glucose thresholds and introduction of virtual care for monitoring of antenatal glycaemia.

MAIN OUTCOME MEASURES

Intervention at birth, perinatal mortality, large-for-gestational-age infants and neonatal unit admission.

RESULTS

The new diagnostic criteria more often identified GDM women who were multiparous, had higher body mass index (BMI) and greater deprivation, and less frequently had previous GDM (all p < 0.05). During COVID, these women had no differences in the key outcome measures. Of the women, 3% were identified with pre-existing diabetes at antenatal booking. Where OGTT continued during COVID, but virtual care was introduced, outcomes were also similar pre- and during the pandemic.

CONCLUSIONS

Using HbA1c and fasting glucose identified a higher risk GDM population during the pandemic but this had minimal impact on pregnancy outcomes. The high prevalence of undiagnosed pre-existing diabetes suggests that women with GDM risk factors should be offered HbA1c screening in early pregnancy.

Update on gestational diabetes and adverse pregnancy outcomes

PURPOSE OF REVIEW

To explore the recent literature concerning the effect of gestational diabetes (GDM) on adverse pregnancy outcomes (APO).

RECENT FINDINGS

Literature search on PubMed, Medline and British Journal of Obstetrics and Gynaecology was conducted using keywords. Search fields were filtered down to include articles from 2019 onwards. GDM is common during pregnancy and is on the rise because of increasing in obesity rates. GDM tended to show an increased risk of APO compared with non-GDM. Treatment of these pregnancies tended to improve these outcomes, particularly for LGA and macrosomia. Additional factors such as prepregnancy BMI and gestational weight gain (GWG) were shown to influence risk. More studies are needed to determine the true effect on postpartum haemorrhage (PPH) and induction of labour (IOL).

SUMMARY

The review agrees with the findings from previous studies and adds to the current literature. Early intervention to manage glycaemic control and GWG may help improve these outcomes. Public health strategies that tackle obesity rates will help to reduce prepregnancy BMI and, therefore, rates of GDM.

Treatment of women with mild gestational diabetes mellitus decreases the risk of adverse perinatal outcomes

AIMS

Glycemic thresholds used to diagnose gestational diabetes mellitus (GDM) are a continued subject of debate. Lower glycemic thresholds identify women with milder GDM for whom treatment benefit is unclear. We compared adverse maternal and neonatal outcomes in treated and untreated women with mild hyperglycemia.

METHODS

We reviewed 11 553 patient charts from two tertiary care centers and included singleton pregnancies >32-week gestation. GDM was diagnosed using the one- or two-step 75 g oral glucose tolerance test (OGTT) depending on the center. All OGTT results were reviewed. Women with glycemic values falling between the thresholds of the two tests, referred to as intermediate hyperglycemic (IH), defined as FPG 5.1-5.2 mmol/L, 1 h PG 10.0-10.5 mmol/L, or 2 h PG 8.5-8.9 mmol/L at 75 g OGTT, were untreated at center A and treated at center B.

RESULTS

There were 630 women with IH, 334 were untreated (center A) and 296 who were treated (center B). After adjusting for covariates, untreated IH women had significantly higher rates of gestational hypertension (aOR 6.02, P = 0.002), large for gestational age (LGA) (aOR 3.73, P < 0.001) and birthweights > 4000 g (aOR 3.35, P = 0.001). Our results indicate that treating 11 women with IH would prevent one LGA birth and treating 13 would prevent 1 birthweight > 4000 g.

CONCLUSION

The diagnosis of GDM using the two-step OGTT fails to identify subgroups of women with mild hyperglycemia that would benefit from treatment to lower the risk for adverse maternal and neonatal outcomes. Treatment of women with mild hyperglycemia decreased the risk of LGA and birthweight >4000 g by 3-fold.

Stillbirth: prevention and supportive bereavement care

Around half of the two million stillbirths occurring worldwide each year are preventable. This review compiles the most up-to-date evidence to inform stillbirth prevention. Many general maternal health interventions also reduce the risk of stillbirth, for example, antenatal care attendance. This review focuses on specific aspects of care: glucose metabolism, targeted aspirin prophylaxis, clotting and immune disorders, sleep positions, fetal movement monitoring, and preconception and interconception health. In the past few years, covid-19 infection during pregnancy has emerged as a risk factor for stillbirth, particularly among women who were not vaccinated. Alongside prevention, efforts to address stillbirth must include provision of high quality, supportive, and compassionate bereavement care to improve parents' wellbeing. A growing body of evidence suggests beneficial effects for parents who received supportive care and were offered choices such as mode of birth and the option to see and hold their baby. Staff need support to be able to care for parents effectively, yet, studies consistently highlight the scarcity of specific bereavement care training for healthcare providers. Action is urgently needed and is possible. Action must be taken with the evidence available now, in healthcare settings with high or low resources, to reduce stillbirths and improve training and care.

The association between offspring birthweight and future risk of maternal diabetes: A population-based study

AIMS

As an indicator of maternal cardiometabolic health, newborn birthweight may be an important predictor of maternal type 2 diabetes mellitus (diabetes). We evaluated the relation between offspring birthweight and onset of maternal diabetes after pregnancy.

METHODS

This retrospective cohort study used linked population-based health databases from Ontario, Canada. We included women aged 16-50 years without pre-pregnancy diabetes, and who had a live birth between 2006 and 2014. We used Cox proportional hazard regression to evaluate the association between age- and sex-standardized offspring birthweight percentile categories and incident maternal diabetes, while adjusting for maternal age, parity, year, ethnicity, gestational diabetes (GDM) and hypertensive disorders of pregnancy (HDP). Results were further stratified by the presence of GDM in the index pregnancy.

RESULTS

Of 893,777 eligible participants, 14,329 (1.6%) women were diagnosed with diabetes over a median (IQR) of 4.4 (1.5-7.4) years of follow-up. There was a continuous positive relation between newborn birthweight above the 75th percentile and maternal diabetes. Relative to a birthweight between the 50th and 74.9th percentiles, women whose newborn had a birthweight between the 97th and 100th percentiles had an adjusted hazards ratio (aHR) of diabetes of 2.30 (95% CI 2.16-2.46), including an aHR of 2.01 (95% CI 1.83-2.21) among those with GDM, and 2.59 (2.36-2.84) in those without GDM.

CONCLUSIONS

A higher offspring birthweight signals an increased risk of maternal diabetes, offering another potentially useful way to identify women especially predisposed to diabetes.

The Role of Adiponectin during Pregnancy and Gestational Diabetes

Pregnancy involves a range of metabolic adaptations to supply adequate energy for fetal growth and development. Gestational diabetes (GDM) is defined as hyperglycemia with first onset during pregnancy. GDM is a recognized risk factor for both pregnancy complications and long-term maternal and offspring risk of cardiometabolic disease development. While pregnancy changes maternal metabolism, GDM can be viewed as a maladaptation by maternal systems to pregnancy, which may include mechanisms such as insufficient insulin secretion, dysregulated hepatic glucose output, mitochondrial dysfunction and lipotoxicity. Adiponectin is an adipose-tissue-derived adipokine that circulates in the body and regulates a diverse range of physiologic mechanisms including energy metabolism and insulin sensitivity. In pregnant women, circulating adiponectin levels decrease correspondingly with insulin sensitivity, and adiponectin levels are low in GDM. In this review, we summarize the current state of knowledge about metabolic adaptations to pregnancy and the role of adiponectin in these processes, with a focus on GDM. Recent studies from rodent model systems have clarified that adiponectin deficiency during pregnancy contributes to GDM development. The upregulation of adiponectin alleviates hyperglycemia in pregnant mice, although much remains to be understood for adiponectin to be utilized clinically for GDM.

Perinatal outcomes of 221,709 singleton and twin pregnancies after the use of donor versus partner sperm

OBJECTIVE

To study the association of donor sperm on perinatal outcomes of livebirths conceived via in vitro fertilization (IVF) when compared with partner sperm.

DESIGN

Retrospective cohort study SETTING: National Human Fertilisation and Embryology Authority assisted reproductive technology registry PATIENTS: All live born singletons and twins conceived through IVF with or without intracytoplasmic sperm injection in the United Kingdom between 1991 and 2016 INTERVENTION(S): Donor sperm compared to partner sperm MAIN OUTCOME MEASURE(S): Perinatal outcomes were assessed. The primary outcomes were preterm and very preterm birth; low, very low, high, and very high birthweight; Secondary outcomes were congenital anomaly and health baby. These were assessed for singletons and twins separately.

RESULTS

For singleton livebirths, compared to partner sperm, those conceived with donor sperm were at reduced odds of very preterm (odds ratio [OR], 0.76; 95% confidence interval [CI], 0.63-0.91; adjusted OR [aOR], 0.80; 95% CI, 0.66-0.96), and preterm (OR, 0.90; 95% CI, 0.83-0.98; aOR, 0.93; 95% CI, 0.85-1.01) birth. For birthweight outcomes, donor sperm showed a reduced odds of low (OR, 0.83; 95% CI, 0.76-0.91; aOR, 0.86; 95% CI, 0.78-0.94) and an increased odds of high (OR, 1.15; 95% CI, 1.07-1.23; aOR, 1.09; 95% CI, 1.01-1.17) birthweight. There was no confirmed difference in the odds ratios of very low (OR, 0.88; 95% CI, 0.74-1.06; aOR, 0.94; 95% CI, 0.78-1.13) or very high (OR, 1.21; 95% CI, 1.04-1.40; aOR, 1.15; 95% CI, 0.98-1.34) birthweight. Liveborn twins conceived with donor sperm, compared to partner sperm, were at reduced odds of very low (OR, 0.76; 95% CI, 0.66-0.88; aOR, 0.83; 95% CI, 0.72-0.96) and low (OR, 0.87; 95% CI, 0.81-0.93; aOR, 0.91; 95% CI, 0.85-0.98) birthweight. There was a suggestion of a reduced odds of very preterm (OR, 0.81; 95% CI, 0.70-0.95; aOR, 0.86; 95% CI, 0.74-1.01) and preterm (OR, 0.93; 95% CI, 0.86-1.01; aOR, 0.96; 95% CI, 0.88-1.04) birth. There was considerable uncertainty around the ORs for high (OR, 0.73; 95% CI, 0.31-1.72; aOR, 0.72; 95% CI, 0.29-1.80) and very high (OR, 1.02; 95% CI, 0.39-2.67; aOR, 1.34; 95% CI, 0.50-3.60) birthweight.

CONCLUSION

Although unmeasured confounding remains a possibility, as paternal age, body mass index, and smoking status were unavailable for analysis, women, couples, service providers can be reassured that IVF livebirths conceived with donor sperm have no greater chance of adverse outcomes when compared to partner sperm.

Abnormal placental villous maturity and dysregulated glucose metabolism: implications for stillbirth prevention

OBJECTIVES

In the UK one in 250 pregnancies end in stillbirth. Abnormal placental villous maturation, commonly associated with gestational diabetes, is a risk factor for stillbirth. Histopathology reports of placental distal villous immaturity (DVI) are reported disproportionately in placentas from otherwise unexplained stillbirths in women without formal diagnosis of diabetes but with either clinical characteristics or risk factors for diabetes. This study aims to establish maternal factors associated with DVI in relation to stillbirth.

METHODS

Placental histopathology reports were reviewed for all pregnant women delivering at University College London Hospital between July 2018 to March 2020. Maternal characteristics and birth outcomes of those with DVI were compared to those with other placental lesions or abnormal villous maturation.

RESULTS

Of the 752 placental histopathology reports reviewed, 11 (1.5%) were reported as diagnostic of DVI. Eighty cases were sampled for clinical record analysis. All women with DVI had normal PAPP-A (>0.4 MoM), normal uterine artery Doppler studies (UtA-PI) and were normotensive throughout pregnancy. Nearly one in five babies (2/11, 18.5%) with DVI were stillborn and 70% had at least one high glucose test result in pregnancy despite no formal diagnosis of diabetes.

CONCLUSIONS

These findings suggest that the mechanism underlying stillbirth in DVI likely relates to glucose dysmetabolism, not sufficient for diagnosis using current criteria for gestational diabetes, resulting in placental dysfunction that is not identifiable before the third trimester. Relying on conventional diabetes tests, foetal macrosomia or growth restriction, may not identify all pregnancies at risk of adverse outcomes from glucose dysmetabolism.

Gestational diabetes mellitus and adverse pregnancy outcomes: systematic review and meta-analysis

OBJECTIVE

To investigate the association between gestational diabetes mellitus and adverse outcomes of pregnancy after adjustment for at least minimal confounding factors.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Web of Science, PubMed, Medline, and Cochrane Database of Systematic Reviews, from 1 January 1990 to 1 November 2021.

REVIEW METHODS

Cohort studies and control arms of trials reporting complications of pregnancy in women with gestational diabetes mellitus were eligible for inclusion. Based on the use of insulin, studies were divided into three subgroups: no insulin use (patients never used insulin during the course of the disease), insulin use (different proportions of patients were treated with insulin), and insulin use not reported. Subgroup analyses were performed based on the status of the country (developed or developing), quality of the study, diagnostic criteria, and screening method. Meta-regression models were applied based on the proportion of patients who had received insulin.

RESULTS

156 studies with 7 506 061 pregnancies were included, and 50 (32.1%) showed a low or medium risk of bias. In studies with no insulin use, when adjusted for confounders, women with gestational diabetes mellitus had increased odds of caesarean section (odds ratio 1.16, 95% confidence interval 1.03 to 1.32), preterm delivery (1.51, 1.26 to 1.80), low one minute Apgar score (1.43, 1.01 to 2.03), macrosomia (1.70, 1.23 to 2.36), and infant born large for gestational age (1.57, 1.25 to 1.97). In studies with insulin use, when adjusted for confounders, the odds of having an infant large for gestational age (odds ratio 1.61, 1.09 to 2.37), or with respiratory distress syndrome (1.57, 1.19 to 2.08) or neonatal jaundice (1.28, 1.02 to 1.62), or requiring admission to the neonatal intensive care unit (2.29, 1.59 to 3.31), were higher in women with gestational diabetes mellitus than in those without diabetes. No clear evidence was found for differences in the odds of instrumental delivery, shoulder dystocia, postpartum haemorrhage, stillbirth, neonatal death, low five minute Apgar score, low birth weight, and small for gestational age between women with and without gestational diabetes mellitus after adjusting for confounders. Country status, adjustment for body mass index, and screening methods significantly contributed to heterogeneity between studies for several adverse outcomes of pregnancy.

CONCLUSIONS

When adjusted for confounders, gestational diabetes mellitus was significantly associated with pregnancy complications. The findings contribute to a more comprehensive understanding of the adverse outcomes of pregnancy related to gestational diabetes mellitus. Future primary studies should routinely consider adjusting for a more complete set of prognostic factors.

REVIEW REGISTRATION

PROSPERO CRD42021265837.

Diabetes during Pregnancy: A Maternal Disease Complicating the Course of Pregnancy with Long-Term Deleterious Effects on the Offspring. A Clinical Review

In spite of the huge progress in the treatment of diabetes mellitus, we are still in the situation that both pregestational (PGDM) and gestational diabetes (GDM) impose an additional risk to the embryo, fetus, and course of pregnancy. PGDM may increase the rate of congenital malformations, especially cardiac, nervous system, musculoskeletal system, and limbs. PGDM may interfere with fetal growth, often causing macrosomia, but in the presence of severe maternal complications, especially nephropathy, it may inhibit fetal growth. PGDM may also induce a variety of perinatal complications such as stillbirth and perinatal death, cardiomyopathy, respiratory morbidity, and perinatal asphyxia. GDM that generally develops in the second half of pregnancy induces similar but generally less severe complications. Their severity is higher with earlier onset of GDM and inversely correlated with the degree of glycemic control. Early initiation of GDM might even cause some increase in the rate of congenital malformations. Both PGDM and GDM may cause various motor and behavioral neurodevelopmental problems, including an increased incidence of attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). Most complications are reduced in incidence and severity with the improvement in diabetic control. Mechanisms of diabetic-induced damage in pregnancy are related to maternal and fetal hyperglycemia, enhanced oxidative stress, epigenetic changes, and other, less defined, pathogenic mechanisms.

Association of maternal pre-pregnancy low or increased body mass index with adverse pregnancy outcomes

This study investigated the association between pre-pregnancy body mass index (BMI) and adverse pregnancy outcomes among women participated in the National Free Preconception Health Examination Project in Guangdong Province, China, and explored these associations according to maternal age. Pre-pregnancy BMI was classified into underweight (BMI < 18.5 kg/m²), healthy weight (18.5–23.9 kg/m²), overweight (24.0–27.9 kg/m²), and obesity (≥ 28.0 kg/m²) according to Chinese criteria. Outcomes were preterm birth (PTB, delivery before 37 weeks of gestation), large for gestational age (LGA, birthweight above the 90th percentile for gestational age by infants’ sex), small for gestational age (SGA, birthweight below the 10th percentile for gestational age by infants’ sex), primary caesarean delivery, shoulder dystocia or birth injury, and stillbirth. Adjusted incidence risk ratios (aIRR) were calculated for underweight, overweight and obesity, respectively. Compared with healthy weight, underweight was associated with increased risk of PTB (aIRR 1.06, 95%CI 1.04–1.09) and SGA (1.23, 1.22–1.26) but inversely associated with LGA (0.83, 0.82–0.85), primary caesarean delivery (0.88, 0.87–0.90) and stillbirth (0.73, 0.53–0.99). Overweight was associated with increased risk of LGA (1.17, 1.14–1.19), primary caesarean delivery (1.18, 1.16–1.20) and stillbirth (1.44, 1.03–2.06), but inversely associated with SGA (0.92, 0.90–0.95) and shoulder dystocia or birth injury (0.86, 0.79–0.93). Obesity was associated with increased risk of PTB (1.12, 1.05–1.20), LGA (1.32, 1.27–1.37), primary caesarean delivery (1.45, 1.40–1.50), but inversely associated with SGA (0.92, 0.87–0.97). The aIRRs for underweight, overweight and obesity in relation to these adverse pregnancy outcomes ranged from 0.65 to 1.52 according to maternal age. In Chinese population, maternal pre-pregnancy BMI was significantly associated with the risk of adverse pregnancy outcomes and the risk differs according to maternal age. Further investigation is warranted to determine whether and how counselling and interventions for women with low or increased BMI before pregnancy can reduce the risk of adverse pregnancy outcomes.

Trends in National Canadian Guideline Recommendations for the Screening and Diagnosis of Gestational Diabetes Mellitus over the Years: A Scoping Review

Canada's largest national obstetric and diabetology organizations have recommended various algorithms for the screening of gestational diabetes mellitus (GDM) over the years. Though uniformity across recommendations from clinical practice guidelines (CPGs) is desirable, historically, national guidelines from Diabetes Canada (DC) and the Society of Obstetricians and Gynaecologists of Canada (SOGC) have differed. Lack of consensus has led to variation in screening approaches, rendering precise ascertainment of GDM prevalence challenging. To highlight the reason and level of disparity in Canada, we conducted a scoping review of CPGs released by DC and the SOGC over the last thirty years and distributed a survey on screening practices among Canadian physicians. Earlier CPGs were based on expert opinion, leading to different recommendations from these organizations. However, as a result of the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study, disparities between DC and the SOGC no longer exist and many Canadian physicians have adopted their recent recommendations. Given that Canadian guidelines now recommend two different screening programs (one step vs. two step), lack of consensus on a single diagnostic threshold continues to exist, resulting in differing estimates of GDM prevalence. Our scoping review highlights these disparities and provides a step forward towards reaching a consensus on one unified threshold.

Incidence of large for gestational age and predictive values of third-trimester ultrasound among pregnant women with false-positive glucose challenge test

This cohort study aimed to determine the association between false-positive 50-g GCT and incidence of LGA and to evaluate predictive roles of third-trimester ultrasonographic examination. A total of 200 women with false-positive 50-g GCT and 188 women without GDM risks were enrolled. Third-trimester ultrasonographic examinations were offered. Rate of LGA during third trimester and at birth were compared between groups. Factors associated with LGA and diagnostic properties of third-trimester ultrasonography were evaluated. Incidence of LGA by third-trimester ultrasound and at birth were significantly higher in women with false-positive GCT (19.0% vs. 10.6%, p = .03 and 22% vs. 13.8%; p = .04). Factors associated with LGA included multiparity (adjusted OR 2.32, p = .01), excessive weight gain (adjusted OR 2.57, p = .01) and LGA by ultrasound (adjusted OR 9.79, p < .001). Third-trimester ultrasonography had 47.1% sensitivity, 92.1% specificity and LR + and LR- of 5.96 and 0.57 in identifying LGA infants.Impact statementWhat is already known on this subject? Women with abnormal GCT but normal OGTT (false positive GCT) might have some degree of glucose intolerance so that GDM-related outcomes could develop, including LGA, macrosomia, shoulder dystocia, and caesarean delivery. Roles of ultrasonography in the prediction of LGA and macrosomia has been reported with mixed results.What do the results of this study add? The results showed that the incidence of LGA, by third-trimester ultrasound and at birth, were significantly increased in women with false-positive GCT. Multiparity, excessive weight gain and LGA by third-trimester ultrasound significantly increased the risk of LGA. Third-trimester ultrasonography had 47.1% sensitivity, 92.1% specificity and LR + and LR- of 5.96 and 0.57 in identifying LGA infants.What are the implications of these findings for clinical practice and/or further research? More intensive behavioural and dietary interventions, together with weight gain control and monitoring, may be needed in women with false-positive GCT to minimise the risk of LGA. Third trimester ultrasonographic examination might be helpful to detect and predict LGA at birth and should be included into routine clinical practice. Further studies that are more widely generalisable are needed to elucidate the relationship between false-positive GCT and adverse pregnancy outcomes and to investigate the benefits of ultrasonographic examination in the prediction of LGA and macrosomia.

COVID-19 pandemic gestational diabetes screening guidelines: A retrospective study in Australian women

BACKGROUND AND AIMS

Gestational diabetes (GDM) is one of the most common medical complications of pregnancy and associated with significant perinatal and long-term morbidity. Temporary changes to the diagnostic testing for GDM have been recommended for the COVID-19 pandemic. This study aims to identify what proportion of women with GDM would be missed by the COVID-19 GDM screening criteria. Secondly an analysis of the relationship between HbA1c, fasting blood glucose (FBG) and pregnancy outcomes will be completed.

METHODS

This was a retrospective analysis of all GDM patients at an Australian secondary hospital between January 2019 and February 2020. The proportion of women with GDM who would have been missed using the COVID-19 guidelines was assessed. Patients were divided into groups according to how their GDM was managed during the pregnancy: Diet, Metformin (MF), Insulin and MF + Insulin groups. Differences between the groups were compared using one-way ANOVA and post-hoc analysis was completed using the Bonferroni test. Logistic regression was employed to further compare the differences between the groups.

RESULTS

The study group comprised 237 patients. Sixty patients (25.3%) would not have had GDM detected in their pregnancy using the COVID-19 guidelines. FBG was the most significant predictor for intervention with medication for GDM (p = 0.001).

CONCLUSION

HbA1c and FBG are poor screening tests for GDM. During the COVID-19 pandemic, the OGTT should be given clinical priority in high risk patients. Elevated FBG is a significant predictor for needing medical management and could be used in the future to better enable individualised treatment.

An update on the use of inositols in preventing gestational diabetes mellitus (GDM) and neural tube defects (NTDs)

INTRODUCTION

Obstetric history and maternal body composition and lifestyle may be associated with serious complications both for the mother, such as gestational diabetes mellitus (GDM), and for the fetus, including congenital malformations such as neural tube defects (NTDs).

AREAS COVERED

In view of the recent knowledge, changes in nutritional and physical activity habits ameliorate glycemic control during pregnancy and in turn improve maternal and neonatal health outcomes. Recently, a series of small clinical and experimental studies indicated that supplemenation with inositols, a family of insulin sensitizers, was associated with beneficial impact for both GDM and NTDs.

EXPERT OPINION

Herein, we discuss the most significant scientific evidence supporting myo-inositol administration as a prophylaxis for the above-mentioned conditions.

Exposure to elevated per- and polyfluoroalkyl substances in early pregnancy is related to increased risk of gestational diabetes mellitus: A nested case-control study in Shanghai, China

BACKGROUND

Long-chain per- and polyfluoroalkyl substances (PFASs) and their short-chain alternatives have been produced and used extensively in China. However, it is unclear whether these compounds contribute to the risk of gestational diabetes mellitus (GDM) in women residing in contaminated areas.

OBJECTIVE

The study was performed to explore the association between PFASs varying in chain length and the risk of developing GDM.

METHOD

A nested case-control study was conducted in a prospective cohort of 2,460 pregnant women between July 1, 2017, and January 31, 2019 in Shanghai, China. Twelve PFASs of interest were measured using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF MS) in the sera of pregnant women at 16-20 weeks. GDM was diagnosed by an oral glucose tolerance test administered over 24-28 gestational weeks. The cases and controls were matched by maternal age. The relationship between maternal serum PFAS level and GDM risk was determined by conditional logistic and linear regression analyses.

RESULTS

A total of 165 GDM cases and 330 controls were enrolled in the study cohort. The frequencies of detection of PFHpA, PFDS, and PFOSA were all ≤80%. Hence, they were excluded from any further risk analysis. Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) were detected at relatively high serum levels (medians 6.57 ng/mL and 8.07 ng/mL, respectively). The serum levels of perfluorobutanesulfonic acid (PFBS) and perfluorododecanoic acid (PFDoA) were significantly higher in the GDM group than they were in the control group (P = 0.02 and P < 0.01, respectively) according to a nonparametric Wilcoxon rank sum test. A quartile analysis showed that the odds ratio of GDM would significantly increase at the highest PFBS and PFDoA levels. In the core model, the adjusted ORs were 2.02 (95% CI = 1.04-3.79) and 13.00 (95% CI = 4.74-24.59), respectively, after adjusting for maternal age, sampling time, parity and body mass index [BMI]).

CONCLUSION

Elevated maternal serum PFBS and PFDoA levels in early pregnancy may be associated with a substantially higher GDM risk.

Gestational diabetes mellitus diagnosed at 24 to 28 weeks of gestation in older and obese Women: Is it too late?

Aim/Background

The prevalence of elderly pregnancy and maternal obesity is increasing worldwide. In old and obese women, metabolic derangement affecting fetal growth might be present earlier than the diagnosis of gestational diabetes mellitus (GDM) or even before pregnancy. We thus investigated whether GDM diagnosed at 24–28 weeks of gestation had already affected fetal abdominal growth and, if so, whether elderly pregnancy and/or maternal obesity aggravate fetal abdominal obesity.

Methods

We retrospectively reviewed the medical records of 7820 singleton pregnant women who had been universally screened using a 50-g glucose challenge test (GCT) at 24–28 weeks of gestation, and underwent a 3-h 100-g oral glucose tolerance test (OGTT) if GCT were ≥140mg/dl. GDM and normal glucose tolerance (NGT) were diagnosed using the Carpenter-Coustan criteria. Fetal abdominal obesity was investigated by assessing the fetal abdominal overgrowth ratios (FAORs) of the ultrasonographically estimated gestational age (GA) of abdominal circumference per actual GA by the last menstruation period, biparietal diameter or femur length, respectively. Fetal abdominal overgrowth was defined as FAOR ≥ 90^th percentile. The subjects were divided into four study groups: group 1 (age < 35 years and pre-pregnancy body mass index [BMI] < 25 kg/m²), group 2 (age < 35 years and ≥ 25), group 3 (age ≥ 35 years and BMI < 25), and group 4 (age ≥ 35 years and ≥ 25).

Results

The overall prevalence of GDM was 5.1%, with old and obese group 4 exhibiting the highest prevalence (22.4%). FAORs were significantly higher in the fetus of those with GDM than in the NGT subjects. But, in the subgroup analysis, only old and nonobese group 3 and old and obese group 4 with GDM exhibited significantly higher FAORs than the NGT subjects. Also, risk of fetal abdominal overgrowth was increased in group 3 and 4 subjects with GDM but not in young and nonobese group 1 GDM. The risk of fetal abdominal overgrowth significantly increased with maternal age >35 years, pre-pregnancy BMI >20kg/m², and HbA1c >37.7 mmol/mol (5.6%). In multivariate analyses, maternal age and HbA1c were significantly associated with FAORs.

Conclusion

GDM diagnosed at 24–28 weeks of gestation already affected fetal abdominal obesity in older and/or obese women, but not in younger and nonobese women. Our data suggest that selective screening and appropriate intervention of GDM earlier than 24–28 weeks of gestation might be necessary for high-risk old and/or obese women.

Perinatal Outcomes in Mexican Women with Untreated Mild Gestational Diabetes Mellitus Diagnosed by the International Association of Diabetes and Pregnancy Study Groups Criteria

PURPOSE

To compare the risk of adverse perinatal outcomes (APO) between pregnant women with mild gestational diabetes mellitus (GDM) diagnosed by the International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria, on no specific treatment, versus pregnant women without GDM.

PATIENTS AND METHODS

A retrospective cohort study of pregnant women referred to the Instituto Nacional de Perinatología, in Mexico City, for prenatal care and delivery. Eligibility criteria were singleton pregnancy, age >18 years, gestational age 20-28 weeks, and no history of pre-gestational diabetes. The study population was divided into two groups: Group 1, comprising women with mild GDM defined by one abnormal glucose value at the oral glucose tolerance test (OGTT) according to IADPSG criteria [fasting: 5.1-5.2 mmol/L (92-94 mg/dL) or 2h 8.5-8.56 mmol/L (153-154 mg/dL)], who did not receive specific treatment for GDM, and Group 2, comprising women without GDM, matched for maternal age and pre-gestational body mass index (BMI). Women with two or more abnormal OGTT values, pre-gestational diabetes, any chronic disease, or multiple pregnancies were excluded.

RESULTS

As many as 282 women were included in each group. There were no significant differences in basal characteristics between groups. APO analysis showed that newborn weight was significantly higher in Group 1 (3042.4±499g) vs Group 2 (2910±565g) p=0.003; conversely, the incidence of large for gestational age (LGA) and macrosomic neonates was similar in both groups (6 vs 5.7% and 2.1 vs 2.2%, respectively). There were no differences in rates of preeclampsia and gestational hypertension, cesarean and preterm delivery, or premature rupture of membranes. A sub-analysis by maternal pre-gestational BMI showed that LGA incidence was significantly higher among babies born to women with pre-gestational BMI ≥30 kg/m² in both groups.

CONCLUSION

The risk of APO was similar among Mexican women with mild untreated GDM diagnosed by IADPSG criteria, compared to pregnant women without GDM. Pre-gestational BMI was an independent risk factor for LGA.