Italian risk factor-based screening for gestational diabetes

Prevalence of gestational diabetes and recourse to postpartum oral glucose tolerance test in the Autonomous Province of Trento (Italy)

OBJECTIVE

The occurrence of gestational diabetes (GDM) is increasing worldwide, and such a diagnosis is important for women's health beyond pregnancy. Therefore, many guidelines suggest the re-evaluation of glucose tolerance with a postpartum oral glucose tolerance test (OGTT) in women with GDM. This study reports the prevalence of GDM and the use of a postpartum OGTT in women assisted at maternity units in the Autonomous Province of Trento in the years 2017-2018, investigating the socio-demographic and health-care variables that can facilitate access to the test.

STUDY DESIGN

For the diagnosis of GDM, the International Association of Diabetes and Pregnancy Study Group criteria were used. The Birth Assistance Certificate and the Hospital Information System were used to retrieve clinical and socio-demographic data. Univariate and multivariate analyses were performed to evaluate the stratification of the use of a postpartum OGTT.

RESULTS

In total, 8,308 pregnant women were assisted at the maternity units in Trento. There were 532 recorded cases of GDM (266 cases per year) and the overall average prevalence was 6.4 % (95 % CI, 5.90-6.90), 4.9 % of whom were Italian (95 % CI, 4.38-5.42) and 10.4 %, foreigners (95 % CI, 9.13-11.67). 135 women diagnosed with GDM and residing in Trento out of 513 were evaluated using a postpartum OGTT (26.3%, CI 95% 22.50-30.10), with pathological results in 61 cases (45.2%). In the multivariate analyses, insulin therapy during pregnancy, delivery at a third-level birth point, and a discharge letter informing of the presence of GDM and of the need for a postpartum OGTT were independent factors associated with the probability of carrying out a postpartum OGTT.

CONCLUSIONS

The prevalence of GDM in our study is lower than in previous Italian studies; however, it is consistent with European data. The proportion of women who were assessed using the postpartum OGTT is lower than that reported by previous studies. The health-care factors seem predominant among the socio-demographic characteristics of the cases in influencing access to the test. The awareness of women, the sharing of guidelines among the different sectors of the health system, and an optimal management of the discharge from the birth point are critical in ensuring an optimal follow-up in women with GDM.

The Analytical Reliability of the Oral Glucose Tolerance Test for the Diagnosis of Gestational Diabetes: An Observational, Retrospective Study in a Caucasian Population

The Oral Glucose Tolerance Test (OGTT) is currently the gold standard reference test for the diagnosis of gestational diabetes mellitus (GDM). Several critical issues related to analytical variables have challenged its reproducibility and accuracy. This study aimed to assess the analytical reliability of the OGTT for the diagnosis of GDM. A total of 1015 pregnant women underwent a 2 h 75 g OGTT between 24 and 28 weeks of gestation. As recommended by National Academy of Clinical Biochemistry, we considered the total maximum allowable error for glucose plasma measurement as <6.9%. Assuming the possibility of analytical errors within this range for each OGTT glucose plasma value, different scenarios of GDM occurrence were estimated. GDM prevalence with standard criteria was 12.2%, and no hypothetical scenarios have shown a comparable GDM prevalence. Considering all the three OGTT values estimated at the lowest or the highest allowed value according to total maximum allowable error, GDM prevalence significantly varied (4.5% and 25.3%, respectively). Our results indicate that the OGTT is not completely accurate for GDM diagnosis.

Abnormal umbilical cord insertions in singleton deliveries: placental histology and neonatal outcomes

AIMS

This study aimed to identify any microscopic features associated with abnormal (membranous/velamentous or marginal) placental cord insertions and to analyse their adverse neonatal outcomes.

METHODS

We retrospectively analysed the records-including pathological findings, clinical information and pregnancy outcomes-for 1060 singleton pregnancies, involving newborn delivered after 24 weeks of gestation.

RESULTS

Marginal cord insertions were identified in 26.60% of cases and membranous cord insertions in 2.64%. Subchorionic vessel thrombus was more prevalent in marginal or membranous insertions (0.97%) than in normal cord insertions (0.27%) (p=0.129). Intervillous thrombi (13.73% vs 8.41%, p<0.05) and chorioamnionitis (8.53% vs 5.48%, p=0.089) were more prevalent in normal cord insertions. Premature rupture of membranes was significantly more commonly associated with abnormal (marginal 15.25% and membranous 17.86%) than with normal (9.87%) insertions (p<0.05). Pre-eclampsia was more common in the group with membranous cord insertions (7.14%) than in the other groups (marginal 0.35%; normal 0.80%) (p<0.05). Marginal and membranous placental cord insertions were associated with earlier gestational age at delivery and smaller fetuses than in the group with normal insertions. Intrauterine fetal demise, cardiac malformations and pregestational diabetes were also more common among cases of abnormal cord insertions.

CONCLUSIONS

Subchorionic vessel thrombus and adverse pregnancy-related outcomes were more prevalent in cases of marginal/membranous cord insertion than for normal insertions.

Limiting the Use of Oral Glucose Tolerance Tests to Screen for Hyperglycemia in Pregnancy during Pandemics

We aimed to evaluate each proposal of Australian–New Zealand Societies to limit the number of oral glucose tolerance tests (OGTTs) to diagnose hyperglycemia in pregnancy (HIP) during the coronavirus disease 2019 (COVID-19) pandemic. At our university hospital (2012–2016), we retrospectively applied in 4245 women who had OGTT between 22 and 30 weeks of gestation (reference standard: WHO criteria) the proposals in which OGTT is performed only in high-risk women; in all (Option 1) or high-risk (Option 1-Sel) women with fasting plasma glucose (FPG) 4.7–5.0 mmol/L; in all (Option 2) or high-risk (Option 2-Sel) women without history of HIP and with FPG 4.7–5.0 mmol/L. We also tested FPG measurement alone in all high-risk women. Measuring FPG alone had a sensitivity of 49% (95% confidence interval 45–54) applying universal screening. Option 2 appeared to have the best balance considering the needed OGTT (17.3%), sensitivity (72% (67–76)) and rates of a composite outcome (true negative cases: 10.6%, false positive cases: 24.4%; true positive cases: 19.5%; false negative cases: 10.2%). Consideration of a history of HIP and measuring first FPG can avoid more than 80% of OGTTs and identify women with the highest risk of adverse HIP-related events.

Myo-inositol supplementation to prevent gestational diabetes in overweight non-obese women: bioelectrical impedance analysis, metabolic aspects, obstetric and neonatal outcomes - a randomized and open-label, placebo-controlled clinical trial

This study aims to evaluate the effects of myo-inositol supplementation on gestational diabetes mellitus (GDM) rates and body water distribution in overweight non-obese women. 223 overweight non-obese women pregnant were randomly assigned to the treatment group (2 g of myo-inositol plus 200 µg of folic acid) or to the placebo one (200 µg of folic acid). The treatment lasted until three weeks after delivery. A tetrapolar impedance analyser was used to study body composition. The incidence of GDM was significantly reduced in the myo-inositol group compared with the placebo group. There was a significant increase in TBW, ECW and ICW values in the placebo group compared to the myo-inositol group. We have recorded a significant reduction in the overall incidence of pregnancy-induced hypertension in the myo-inositol group compared with the placebo group. Our results demonstrate the effectiveness of myo-inositol supplementation in preventing GDM in overweight non-obese pregnant women.

Appropriate Timing of Gestational Diabetes Mellitus Diagnosis in Medium- and Low-Risk Women: Effectiveness of the Italian NHS Recommendations in Preventing Fetal Macrosomia

BACKGROUND

Screening strategies for gestational diabetes mellitus (GDM) earlier than 24-28 weeks of gestation should be considered to prevent adverse pregnancy outcomes. Nonetheless, there is uncertainty about which women would benefit most from early screening and which screening strategies should be offered to women with GDM. The Italian National Healthcare Service (NHS) recommendations on selective screening for GDM at 16-18 weeks of gestation are effective in preventing fetal macrosomia in high-risk (HR) women, but the appropriateness of timing and effectiveness of these recommendations in medium- (MR) and low-risk (LR) women are still controversial. Patients and Methods. We retrospectively enrolled 769 consecutive singleton pregnant women who underwent both anomaly scan at 19-21 weeks of gestation and screening for GDM at 16-18 and/or 24-28 weeks of gestation, in agreement with the NHS recommendations and risk stratification criteria. Comparison of maternal characteristics, fetal biometric parameters at anomaly scan (head circumference (HC), biparietal diameter (BPD), abdominal circumference (AC), femur length (FL), estimated fetal weight (EFW)), and neonatal birth weight (BW) percentile among risk groups was examined.

RESULTS

219 (28.5%) women were diagnosed with GDM, while 550 (71.5%) were normal glucose-tolerant women. Out of 164 HR women, only 62 (37.8%) underwent the recommended early screening for GDM at 16-18 weeks of gestation. AC and EFW percentiles, as well as neonates' BW percentiles, were significantly higher in HR women diagnosed with GDM at 24-28 weeks of gestation with respect to normal glucose-tolerant women, as well as MR and LR women who tested positive for GDM. Comparative analysis between MR and LR women with GDM and women with normal glucose tolerance revealed significant differences in both AC and EFW percentiles (P < 0.05), while there was no significant difference in neonatal BW percentiles.

CONCLUSION

In MR and LR women with GDM, a mild acceleration of fetal growth can be detected at the time of anomaly scan. However, in these at-risk categories, the NHS recommendations for screening and treatment of GDM at 24-28 weeks of gestation are still effective in normalizing BW and preventing fetal macrosomia, thus supporting a risk factor-based selective screening program for GDM.

Guidelines for the screening and diagnosis of gestational diabetes in Italy from 2010 to 2019: critical issues and the potential for improvement

AIMS

In 2010, Italian health professionals rapidly implemented the one-step screening for gestational diabetes mellitus (GDM) based on a 75 g OGTT, to comply with the diagnostic criteria proposed by the International Association of Diabetes and Pregnancy Study Groups (IADPSG). The change was promoted by the two main Italian scientific societies of diabetology, Associazione Medici Diabetologi (AMD) and Società Italiana di Diabetologia (SID), and it took just a few months for the Istituto Superiore di Sanità, together with several scientific societies, to revise the criteria and include them in the National Guidelines System. Over the last 9 years, the implementation of these guidelines has shown some benefits and some drawbacks.

METHODS

In order to evaluate the critical issues arisen from the implementation of the current Italian guidelines for the diagnosis of GDM, the studies published on this topic have been reviewed. The search was performed using the following keywords: "gestational diabetes" AND "diagnostic criteria" OR screening AND Ital*. The study is an expert opinion paper, based on the relevant scientific literature published between 2010 and 2019. The databases screened for the literature review included PubMed, MEDLINE, and Scopus.

RESULTS

The implementation of the Guidelines for Screening and Diagnosis of GDM in Italy present some strengths and some weaknesses. One of the positive aspects is that high-risk women are required to perform an OGTT early in pregnancy. By contrast, there are several aspects in need of improvement: (1) In spite of the current indications, only a minority of high-risk women perform OGTT early in pregnancy; (2) several low-risk women are screened for GDM; (3) in some low-risk women affected by GDM, the diagnosis might be missed with the application of the current guidelines; (4) there is a lack of homogeneity in the risk assessment data from different regions.

CONCLUSIONS

In order to improve the current Italian GDM guidelines, some practical solutions have been suggested.

Maternal age and the risk of adverse pregnancy outcomes: a retrospective cohort study

Background

The increased potential for negative pregnancy outcomes in both extremes of reproductive age is a well-debated argument. The aim of this study was to analyze the prevalence and the outcome of pregnancies conceived at extreme maternal ages.

Methods

This retrospective study considered all single consecutive pregnancies delivered in a tertiary referral center between 2001 and 2014. Patients were categorized into 4 groups according to maternal age at delivery (< 17 years; 18–28 years; 29–39 years; > 40 years). The following outcomes were considered (amongst others): pregnancy-related hypertensive disorders (PRHDs), neonatal resuscitation (NR), neonatal intensive care unit (NICU) admission, periventricular leucomalacia (PVL), and grade 3 and 4 intraventicular hemorrhage (IVH).

Results

During the considered period 22,933 single pregnancies gave birth in our unit. We observed 71 women aged < 17 years, and 1552 aged > 40 years. In each year throughout the study period, there was a significant increment in maternal age of 0.041 years (95% CI 0.024–0.058) every new year. Multivariate analysis concluded out that maternal age over 40 years was an independent risk factor for preterm delivery (OR 1.36 95% CI 1.16–1.61, p < 0.05, PRHDs (OR 2.36 95% CI 1.86–3.00, p < 0.05), GDM (OR 1.71 95% CI 1.37–2.12, p < 0.05) cesarean section (OR 1.99 95% CI 1.78–2.23, p < 0.05), abnormal fetal presentation (OR 1.29 95% CI 1.03–1.61, p < 0.05), and fetal PVL (OR 3.32 95% CI 1.17–9.44, p < 0.05). We also observed that maternal age under 17 years or over 40 years was an independent risk factor for grade 3 or 4 neonatal IVH (OR 2.97 95% CI 1.24–7.14, p < 0.05).

Conclusions

These findings confirm a negative impact of extreme maternal ages on pregnancy. These results should be carefully taken into account by maternal care providers in order to inform women adequately, supporting them in understanding potential risks associated with their procreation choices, and to improve clinical surveillance.

Electronic supplementary material

The online version of this article (10.1186/s12884-019-2400-x) contains supplementary material, which is available to authorized users.

The risk stratification of adverse neonatal outcomes in women with gestational diabetes (STRONG) study

AIMS

To assess the risk of adverse neonatal outcomes in women with gestational diabetes (GDM) by identifying subgroups of women at higher risk to recognize the characteristics most associated with an excess of risk.

METHODS

Observational, retrospective, multicenter study involving consecutive women with GDM. To identify distinct and homogeneous subgroups of women at a higher risk, the RECursive Partitioning and AMalgamation (RECPAM) method was used. Overall, 2736 pregnancies complicated by GDM were analyzed. The main outcome measure was the occurrence of adverse neonatal outcomes in pregnancies complicated by GDM.

RESULTS

Among study participants (median age 36.8 years, pre-gestational BMI 24.8 kg/m²), six miscarriages, one neonatal death, but no maternal death was recorded. The occurrence of the cumulative adverse outcome (OR 2.48, 95% CI 1.59-3.87), large for gestational age (OR 3.99, 95% CI 2.40-6.63), fetal malformation (OR 2.66, 95% CI 1.00-7.18), and respiratory distress (OR 4.33, 95% CI 1.33-14.12) was associated with previous macrosomia. Large for gestational age was also associated with obesity (OR 1.46, 95% CI 1.00-2.15). Small for gestational age was associated with first trimester glucose levels (OR 1.96, 95% CI 1.04-3.69). Neonatal hypoglycemia was associated with overweight (OR 1.52, 95% CI 1.02-2.27) and obesity (OR 1.62, 95% CI 1.04-2.51). The RECPAM analysis identified high-risk subgroups mainly characterized by high pre-pregnancy BMI (OR 1.68, 95% CI 1.21-2.33 for obese; OR 1.38 95% CI 1.03-1.87 for overweight).

CONCLUSIONS

A deep investigation on the factors associated with adverse neonatal outcomes requires a risk stratification. In particular, great attention must be paid to the prevention and treatment of obesity.

Screening for gestational diabetes in Tuscany, Italy. A population study

AIMS

According to current Italian guidelines, only women at higher risk of gestational diabetes (GDM) are eligible for receiving a glucose tolerance test (OGTT) during pregnancy. This study evaluates the compliance to national guidelines, additionally proposing an algorithm able to identify women with GDM.

METHODS

The study included 23,270 pregnant women aged >15yr, resident in Tuscany, a region in central Italy, delivering in year 2015, identified by certificates of care at delivery. Eligibility to screening was evaluated by fulfillment to regional guidelines recommending a 2-h-75g-OGTT only in presence of risk factors. Additionally, a validated algorithm is proposed to diagnose GDM from regional administrative databases.

RESULTS

Glucose tolerance was tested in 79.2% of women. Eligibility criteria were fulfilled in 55.6% of OGTT performers and in 40.2% of those who didn't perform any OGTT. Performers' rate increased with age, body weight, higher education degree and in those followed by a well defined clinical setting. Housewives and students had a lower chance of receiving an OGTT. Algorithm identified GDM in 11% of women, ranging from 14% among eligible and 7% among non-eligible ones.

CONCLUSION

Selective screening for GDM is not being currently applied in Tuscany. Despite the percentage of eligible women by national guidelines was 55%, the rate of those who performed the screening was about 80%, with a 40% of low risk women continuing to be screened. Moreover, GDM rate, calculated by algorithm, was relatively large (7%) among non-eligible women, suggesting the need of universal glucose screening to adequately capture all GDM cases.

Italian national guidelines for the screening of gestational diabetes: Time for a critical appraisal?

BACKGROUND AND AIM

In 2011, the Italian National Health System guidelines introduced a selective screening for gestational diabetes (GDM) based on risk factors, recommending early evaluation in high risk women. The present study examined to which extent guidelines are applied, and analyzed the effectiveness of GDM diagnosis according to risk profile.

METHODS AND RESULTS

We analyzed 1338 pregnant women, consecutively screened for GDM with a 75 g OGTT between January 2013 and December 2015, according to national guidelines. Diagnosis of GDM was based on IADPSG/WHO 2013 criteria. As many as 14.4% of screened women was at high risk, 64% at medium, 21.6% did not have any risk factor. Only 50% of high-risk women were appropriately screened at 16th-18th gestational weeks; 28% of them repeated the OGTT due to NGT. The overall prevalence of GDM was 39.9%, higher in high risk women (67% vs. 40% medium risk vs. 22% low risk; p < 0.0001). An early GDM diagnosis was performed in 40.7% of high-risk women. In low risk women, gestational weight gain at the screening time was independently associated with GDM.

CONCLUSIONS

The recommendations for the screening of GDM are still insufficiently implemented, especially for early evaluation in high risk women. Considering the high proportion of early GDM diagnosis, the poor adherence to screening recommendation may result in late diagnosis of GDM. Finally, our finding of a 22% prevalence of GDM among low risk women suggests the need to consider additional risk factors, such as excessive weight gain during pregnancy.

Transitional hemodynamics in infants of diabetic mothers by targeted neonatal echocardiography, electrocardiography and peripheral flow study

OBJECTIVE

Metabolic alterations of intrauterine environment in diabetes mellitus (DM) lead to fetal cardiac dysfunctions that can persist after birth. The aim of the study was to assess the cardiovascular adaptation in infants born to diabetic mothers (IDM) with different degrees of glycometabolic control, in relation to revised guidelines for diagnosis of DM and quality improvements in neonatal care.

MATERIALS AND METHODS

An observational case-control study was conducted on IDM with gestational, type 1 and type 2 DM. Relevant maternal and neonatal anamnestic, clinical and laboratory data were analyzed. Electrocardiographic and echocardiographic analyses, including structural and systo-diastolic evaluation, were performed.

RESULTS

In 68 IDM enrolled, we observed a lower incidence of negative perinatal outcome than expected. Comparing to non-IDM, they presented larger fetal shunts, higher pulmonary pressures, early and atrial wave velocities. At 72 hours, kinesis and heart rate variability remained low. Cerebral blood flow velocities were higher. The most serious impairment of transition was in pregestational IDM.

CONCLUSION

Maternal DM impaired neonatal transitional hemodynamics also in asymptomatic IDM with good glycometabolic control. These results confirm the need for an early cardiologic and cerebrovascular evaluation, to identify IDM with delayed maturation at risk of worse long-term metabolic, cardiovascular, and neurodevelopmental outcome.

A critical appraisal and potentially new conceptual approach to screening and diagnosis of gestational diabetes

The aim of this article was a critical appraisal of current GDM screening and diagnosis status as well as a presentation of a potentially new approach to this perinatologic and public health problem of increasing clinical significance. Medline, EMBASE and Cochrane databases were searched. Most professional organisations recommend universal screening at 24-28 weeks of gestation, while some of them state that selective screening could also be recommended. Expert opinions regarding GDM diagnosis significantly differ throughout the world. Authors call for an open and broad professional and scientific discussion and suggest a combination of screening and diagnosis procedures in a form of one-step 1-h screening method, creation of regional GDM diagnostic criteria and standardisation of outcome-based randomised control trials. They also advise introduction of a conceptually new approach, where the risk of hyperglycaemia rather than insisting on GDM diagnosis itself should be detected.

Level of implementation of guidelines on screening and diagnosis of gestational diabetes: A national survey

AIMS

To describe the degree of diffusion and acceptance of national guideline on screening and diagnosis of gestational diabetes (GDM) among Italian diabetes centers and to detect possible areas for benchmarking.

METHODS

In 2013 the Italian Diabetes in Pregnancy Study Group structured a national survey, focused on GDM screening and diagnostic procedures, that was administered to diabetologists.

RESULTS

Overall, 122 diabetologists of 122 different diabetes centers (21.7% territorial, 78.3% hospital/University) completed the questionnaire. All respondents declared to execute a 75 g-oral glucose tolerance test (OGTT) as diagnostic test. Almost one in five centers preferred a universal screening procedure, the others executing a selective risk factors-based screening. In patients at high risk for GDM the OGTT was performed at 16-18 weeks' gestation in 84.0% of the cases; only 6.5% of respondents preferred to execute it as soon as possible; and 9.5% used to wait until 24-28 weeks' gestation. In the case of fasting plasma glucose (FPG) ≥ 5.1 mmol/l (92 mg/dl), two third of respondents used to proceed with the execution of the complete diagnostic OGTT, the others considering sufficient the FPG value for the diagnosis.

CONCLUSIONS

Good level of reception of national recommendations was documented. The diagnostic procedure was generally accepted and applied. Some criticisms were specifically linked to the choice of universal or risk factor-based screening procedure, and to the right time for executing the OGTT in women at high risk.

Myo-Inositol Supplementation to Prevent Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is a common complication characterized by increased insulin resistance, and by increased risk for adverse pregnancy outcomes affecting both the mother and the fetus. International guidelines describe optimal ways to recognize it, and the recommended treatment of patients affected to reduce adverse outcomes. Improving insulin resistance could reduce incidence of GDM and its complications. Recently, a few trials have been published on the possible prevention of GDM. Inositol has been proposed as a food supplement that might reduce gestational diabetes incidence in high-risk pregnant women.

Myo-inositol may prevent gestational diabetes onset in overweight women: a randomized, controlled trial

OBJECTIVE

To evaluate whether myo-inositol supplementation may reduce gestational diabetes mellitus (GDM) rate in overweight women.

METHODS

In an open-label, randomized trial, myo-inositol (2 g plus 200 μg folic acid twice a day) or placebo (200 μg folic acid twice a day) was administered from the first trimester to delivery in pregnant overweight non-obese women (pre-pregnancy body mass index ≥ 25 and < 30 kg/m(2)). The primary outcome was the incidence of GDM.

RESULTS

From January 2012 to December 2014, 220 pregnant women were randomized at two Italian University hospitals, 110 to myo-inositol and 110 to placebo. The incidence of GDM was significantly lower in the myo-inositol group compared to the placebo group (11.6% versus 27.4%, respectively, p = 0.004). Myo-inositol treatment was associated with a 67% risk reduction of developing GDM (OR 0.33; 95% CI 0.15-0.70).

CONCLUSIONS

Myo-inositol supplementation, administered since early pregnancy, reduces GDM incidence in overweight non-obese women.

Gestational diabetes mellitus: An update on the current international diagnostic criteria

The approach to screening and diagnosis of gestational diabetes mellitus (GDM) around the world is disorderly. The protocols for diagnosis vary not only in-between countries, but also within countries. Furthermore, in any country, this disparity occurs in-between its hospitals and often exists within a single hospital. There are many reasons for these differences. There is the lack of an international consensus among preeminent health organizations (e.g., American College of Gynecologists and World Health Organization). Often there is a disagreement between the country's national diabetes organization, its local health society and its regional obstetric organization with each one recommending a different option for approaching GDM. Sometimes the causes for following an alternate approach are very obvious, e.g., a resource strapped hospital is unable to follow the ivory-tower demanding recommendation of its obstetric organization. But more often than not, the rationale for following or not following a guideline, or following different guideline within the same geographic area is without any perceivable explanation. This review is an attempt to understand the problems afflicting the screening and diagnosis of GDM globally. It traces the major temporal changes in the diagnostic criteria of (1) some respected health organizations; and (2) a few selected countries. With an understanding of the reasons for this disparity, a way forward can be found to reach the ultimate goal: a single global guideline for GDM followed worldwide.