Diagnostic criteria for gestational diabetes in relation to pregnancy outcome

OBJECTIVES: To determine which of the American Diabetes Association (ADA) or World Health Organization (WHO) plasma glucose criteria for gestational diabetes mellitus (GDM) best predicts poor fetal outcome. To determine whether an alternative cut-off point would result in increased predictive value and greater diagnostic effectiveness in pregnancies at high risk for GDM. RESEARCH DESIGN AND METHODS: A sample of 473 successive apparently normal pregnant women attending the Obstetric Department were screened for GDM using both the ADA and the WHO criteria. Between 26 and 30 weeks of gestation, they underwent, on subsequent days, a screening test with a 50-g oral glucose load and two oral glucose tolerance tests (OGTTs) with 75 and 100 g of glucose according to the WHO and the ADA recommendations, respectively. From this group, we identified 99 women at high risk for GDM, who did not attend their pregnancy follow-up and whose delivery records were recovered at our hospital or in neighbouring hospitals. This unusual situation enabled us to study the natural history and outcome of their pregnancy in spite of not receiving special management usually provided to such women. As macrosomia was expected to be the most frequent undesirable foetal outcome, sensitivity and specificity calculations have been based on this outcome. RESULTS: The study population (n=99) had a median parity of two and 14% had abnormal results in the 2-h, 75-g load test (WHO) vs. 6% in the 100-g test (ADA). Optimal cut-off points for each test were lower than those recommended for diagnosis by the ADA and the WHO. The optimal sensitivity for the 1-h, 50-g test was 66.7% (cut-off 137 mg/dl), and for the 2-h, 75-g test (cut-off 119 mg/dl). The best specificity and positive predictive value was for this last test with a cut-off point of 140 mg/dl in the second hour. CONCLUSIONS: The standard 2-h cut-off value of 140 mg/dl for the 75-g test, as now recommended by WHO, was optimal for predicting macrosomia. Based on the sensitivity and specificity for macrosomia, the 1-h, 50-g screening test had an optimal cut-off point of 137 mg/dl (vs. 140 mg/dl recommended by ADA). The 2-h, 75-g OGTT value using a cut-off point of 119 mg/dl had equivalent sensitivity, specificity, and positive predictive value. In contrast, the 100-g OGTT had much lower levels of sensitivity, but higher specificity and higher positive predictive value.     

Comparison of National Diabetes Data Group and World Health Organization criteria for detecting gestational diabetes mellitus

Summary We compared the criteria for diagnosis of gestational diabetes mellitus (GDM) of the National Diabetes Data Group (NDDG) and the World Health Organization (WHO) and studied the outcomes of pregnancy. A 50-g glucose screening test and 75-g oral glucose tolerance test (OGTT) were scheduled for 709 pregnant women in the same week between the 24th and 28th week of pregnancy. Blood glucose was measured 1 h after the 50-g glucose screening test and if found to be 7.8 mmol/l or more, a 100-g OGTT was scheduled within 7 days after a 75-g OGTT. The prevalence of GDM was found to be 1.4% (10/709) and 15.7% (111/709) by NDDG and WHO criteria (2 h 7.8 mmol/l), respectively. Using NDDG criteria, all the GDM patients had abnormal 75-g OGTT by WHO criteria. NDDG and WHO criteria were significantly different when compared with normal OGTT by each criteria for age, BMI, pregnancy-induced hypertension, Caesarian delivery, macrosomia and neonatal hypoglycaemia. Of 14 women with macrosomic infants 6 had an abnormal WHO test while only 3 of 14 had an abnormal NDDG test. These findings suggest that WHO criteria GDM patients had significantly worse outcomes of pregnancy and fewer perinatal complications were missed than with the more cumbersome NDDG criteria, and no case of GDM as diagnosed by NDDG criteria was missed.Abbreviations GDM Gestational diabetes mellitus - NDDG National Diabetes Data Group - WHO World Health Organization - OGTT oral glucose tolerance test - BMI body mass index     

Comparison of screening for gestational diabetes mellitus by oral glucose tolerance tests done in the non-fasting (random) and fasting states

Aim

The Diabetes in Pregnancy Study Group of India (DIPSI) guidelines recommend the non-fasting 75-g oral glucose tolerance test (OGTT) as a single-step screening and diagnostic test for gestational diabetes mellitus (GDM). The aim of this study was to compare the DIPSI criteria with the World Health Organization (WHO) 1999 and the International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria for GDM.

Methods

A total of 1,031 pregnant women attending antenatal clinics in urban and rural Tamil Nadu, India, underwent a 75-g OGTT in both non-fasting and fasting states, 2–3 days apart. Venous plasma glucose was measured using an autoanalyser, and GDM was diagnosed by DIPSI, WHO 1999 and IADPSG criteria.

Results

Of the 83 women identified to have GDM by WHO 1999 criteria, only 23 were diagnosed by DIPSI criteria. Of the 106 women diagnosed to have GDM by the IADPSG criteria, only 24 were diagnosed by DIPSI. The DIPSI non-fasting OGTT 2-h VPG cut point of 140 mg/dl (7.8 mmol/l) had a very low sensitivity when compared to the WHO 1999 criteria (sensitivity 27.7 %, specificity 97.7 %) and IADPSG criteria (sensitivity 22.6 %, specificity 97.8 %).

Conclusions

The DIPSI non-fasting OGTT criteria cannot be recommended for diagnosis of GDM due to its low sensitivity. Thus, as a single-step diagnostic test for GDM, the fasting OGTT needs to be done. When this is not possible, the well-established two-step procedure using the 50-g glucose challenge test as an initial screening test, followed by the diagnostic fasting OGTT, can be continued.     

Can either oral glucose challenge test or oral glucose tolerance test parameters predict gestational diabetes mellitus?

This study aims to evaluate the relationship between the glucose challenge test (GCT) levels and any of the oral glucose tolerance test (OGTT) parameters (fasting plasma glucose (FPG), 1-, 2-, or 3-h plasma glucose levels) and their effect on predicting gestational diabetes mellitus (GDM). This analysis was carried out as a retrospective study at Obstetrics and Gynecology Clinic of Turgut Özal University Hospital. Oral GCT were conducted on patients who are at 24–29 weeks’ gestation. The study participants with positive GCT results underwent a 3-h, 100-g OGTT, and the resulting values were evaluated using Carpenter and Coustan diagnostic criteria to determine the gestational glucose tolerance status of patients. The data obtained from both tests (GCT, FPG, 1-, 2-, 3-h OGTT values) were analyzed to observe the effect of each group on predicting GDM. Although all of the GCT and OGTT values were found to be statistically significant (p?<?0.001) in determining GDM, the 2-h values of OGTT detected almost all GDM cases with a very high sensitivity level (94.5 %). The 1-h values on the other hand identified 87.6 % of GDM (p?<?0.001). The GCT value with the highest sensitivity and specificity for predicting GDM was calculated as 154.50 mg/dl (sensitivity and specificity rates were 79.2 and 72.8 %, respectively). A 2-h OGTT glucose level can detect GDM with 94.5 % sensitivity. This result can guide clinicians to evaluate the patients with GDM.     

Fasting plasma glucose as a screening test for gestational diabetes in a multi-ethnic, high-risk population.

AIMS: Screening every pregnant woman for gestational diabetes mellitus (GDM), as widely recommended for high-incidence populations, strains the healthcare system excessively. This study investigated the value of fasting plasma glucose (FPG) as an alternative to the more cumbersome oral glucose tolerance test (OGTT). METHODS: One thousand six hundred and forty-four pregnant women in a multi-ethnic, high-risk population were evaluated by the FPG as a screening test among two principal subgroups, i.e. women (n = 1276) at risk for GDM on clinical grounds and those women (n = 368) with a positive post 50-g, 1-h plasma glucose challenge test (GCT). Two threshold values for FPG 'ruled in or ruled out' a GDM diagnosis, which was confirmed by the 3-h, 100-g OGTT, using Carpenter's modified criteria as the 'gold standard'. RESULTS: In the women with a positive clinical history, at an optimal cut-off value of FPG < 4.4 mmol/l to rule out GDM; a sensitivity of 94.7% was achieved, 21 (1.6%) women being false negatives. Using a FPG > or = 5.3 mmol/l to rule in GDM; the specificity was 94.0% with 53 (4.2%) women being classified as false positives. FPG would have eliminated need for the OGTT in 50.9% pregnant women (misclassification rate 5.8%). In the positive GCT group, using similar cut-offs for FPG, a sensitivity of 96.6% and specificity of 90.8% was achieved with a potential to avoid 51.6% OGTTs (misclassification rate 7.3%). The positive predictive value of the GCT was 31.8% compared to 80.2% for FPG at 5.3 mmol/l. CONCLUSIONS: While previously neglected as a screening test for GDM, in selected high-risk populations the FPG offers a potentially simple, practical algorithm to screen for GDM by being cost-effective and patient friendly. A wider application should be explored.     

Placental weight and placental weight-to-birth weight ratio are increased in diet- and exercise-treated gestational diabetes mellitus subjects but not in subjects with one abnormal value on 100-g oral glucose tolerance test

The aim of the present study was to determine whether the placental weight and placental weight-to-birth weight ratio (PW/BW) increased in pregnant women with one abnormal value (OAV) on 100-g oral glucose tolerance test (OGTT) and diet- and exercise-treated, non-insulin-requiring gestational diabetes mellitus (GDM) subjects. The 50-g glucose challenge test (GCT) was administered to 324 pregnant women. Women with abnormal 50-g test received a 100-g, 3-h OGTT using National Diabetes Data Group criteria. Women with GDM and OAV were treated with diet and exercise. Twenty subjects who required insulin or met exclusion criteria were excluded from the study. After the exclusion of 20 subjects, the GDM group consisted of 30 (9.7%) pregnant women and the OAV group consisted of 32 (9.9%) pregnant women. The control group consisted of 242 pregnant women. Birth weight (GDM: 3288.3+/-364.2 g; OAV: 3278.1+/-409.9 g; control group: 3270.6+/-346.5 g) did not differ significantly between groups (P>.05). Significantly higher placental weights (GDM: 694.8+/-152.1 g; OAV: 622.2+/-105.3 g; control group: 610.2+/-116.6 g; P<.01) and PW/BW (GDM: 0.21+/-0.03; OAV: 0.193+/-0.04; control group: 0.188+/-0.04; P<.01) were observed in GDM group compared to OAV and control group. No significant difference was found for OAV group in terms of placental weight and PW/BW compared to the control group. Our data indicated that women with OAV delivered infants and placenta of similar weight to those of normal pregnancies.     

Prevalence and risk factors for gestational diabetes assessed by universal screening

In order to evaluate the prevalence of gestational diabetes mellitus (GDM) and the presence of risk factors for GDM, we conducted a retrospective study of a cohort of Italian women. In addition, we compared universal versus selective screening to validate the ADA's recommendations in our population. From June 1st, 1995 to December 31st, 2001, universal screening for GDM was performed in 3950 women. The glucose challenge test (GCT) was positive (GCT+) in 1389 cases (35.2%). The 1-h glucose level after GCT enabled us to diagnose GDM directly in 24 pregnant women. Oral glucose tolerance test (OGTT) was performed in 1221 GCT+ women (144 cases with GCT+ dropped out) and GDM was diagnosed in 284 (23.2%) of them. OGTT was also performed in 391 randomly chosen, women from the GCT negative (GCT-) group. In this last group 25 (6.3%) women had GDM. Thus, the total number of subjects with GDM was 333 out of 3806 with a prevalence of 8.74% in the entire cohort. Assuming that the rate of GDM observed in the random sample of GCT- women is applicable to the whole group of 2561 GCT- women, then 161 GCT- patients could also have GDM. This will further increase the estimated prevalence for the whole cohort up to 12.3% (i.e. 469 out of 3806 pregnant women). There were 236 (5.6%) women with a low risk for GDM (normal weight, age less than 25 years and without a family history of diabetes). In this group we found 34 cases and five cases with positive screening test and GDM, respectively. Thus, if we excluded low risk women from the screening test, as suggested by ADA recommendations, only five women with GDM would have been missed. However, about 95% of our population were at medium or high risk for GDM and, therefore, would have been screened. The rate of GDM was significantly higher in women with a positive history of diabetes, increasing age, previous pregnancies, pre-pregnancy overweight and short stature. After logistic regression analysis, GDM diagnosis was significantly correlated with age (P<0.0001), pre-pregnancy BMI (P<0.0001), weight gain (P<0.0001) and family history of diabetes (P<0.01).     

The effect of glucose levels on fetal birth weight: a study of Chinese gravidas in Tianjin, China

The relationship between maternal glucose intolerance and fetal birth weight remains, to a large extent, unknown in Chinese gravidas. From December 1998 to December 1999, 9471[corrected] women in six urban districts of Tianjin, China, underwent an initial screening using a 50-g, 1-h glucose load at 26-30 gestational weeks. Women with a serum glucose reading >or=7.8 mmol/l, were followed up for a 75-g, 2-h glucose tolerance test, which was interpreted using the 1998 World Health Organization's (WHO) criteria for diabetes. A total of 174 women had gestational diabetes mellitus. Complete data was collected in 170 women. Among them, 56 accepted diabetes management including self-home glucose monitoring, diet, and physical activity advice, and others received no treatment. The comparison group was 302 women with normal glucose tolerance (NGT). Glucose levels at the initial screening (partial R(2)=.0343, P<.0001), maternal weight gain during pregnancy (partial R(2)=.0915, P<.0001), and gestational week at delivery (partial R(2)=.0432, P<.0001) were determinants of fetal birth weight, controlling for maternal age, pregravid BMI, maternal stature, and other confounders. Both gestational diabetes mellitus (GDM) status and a positive screening but normal oral glucose tolerance test (OGTT) result were predictors of macrosomia (birth weight >or=4000 g). It concludes that maternal glucose levels correlate with fetal birth weight and a glucose level of 7.8 mmol/l or more at the initial screening is predictive of macrosomia in Chinese gravidas regardless of GDM status.     

Universal vs. risk factor-based screening for gestational diabetes mellitus: detection rates, gestation at diagnosis and outcome.

AIMS: Gestational diabetes mellitus (GDM) is associated with adverse maternal and fetal outcome. Screening for GDM is therefore recommended but the best screening method remains controversial. This prospective, randomized study compared a risk factor-based screening programme with a universally based one. METHODS: Subjects were randomized at booking to one of two groups: the risk factor group had a 3-h 100-g oral glucose tolerance test (OGTT) at 32 weeks if any risk factor for GDM was present; the universal group had a 50-g glucose challenge test performed and if their plasma glucose at 1 h was > or = 7.8 mmol/l, a formal 3-h 100-g OGTT was then performed. RESULTS: Universal screening detected a prevalence of GDM of 2.7%, significantly more than the 1.45% detected in the risk factor screened group (P<0.03). Universal screening facilitated earlier diagnosis than risk factor screening - mean gestation 30 +/- 2.6 weeks vs. 33 +/- 3.7 weeks (P<0.05). A higher rate of spontaneous vaginal delivery at term, and lower rates of macrosomia, Caesarean section, prematurity, pre-eclampsia and admission to neonatal intensive care unit were observed in the universally screened, early diagnosis group. CONCLUSIONS: Universal screening for GDM is superior to risk factor based screening-detecting more cases, facilitating early diagnosis and is associated with improved pregnancy outcome.     

Asymmetric dimethylarginine level in hyperglycemic gestation

We aimed to evaluate plasma asymmetric dimethylarginine (ADMA) concentrations and its relation with insulin sensitivity/resistance indices in pregnant women with different degrees of carbohydrate intolerance. This study included a two step approach; 50 g glucose challenge test (GCT) followed by 100 g oral glucose tolerance test (OGTT) was used for diagnosis of carbohydrate intolerance within 24-28th weeks of gestation. Pregnant women with positive GCT but negative OGTT (AGCT group, n=30) and gestational diabetics (GDM group, n=58) were compared to healthy pregnant controls (n=50). Plasma ADMA concentration and its relationship with glucose and insulin levels and insulin sensitivity/resistance indices (HOMA-IR, QUICKI, ISIOGTT) were evaluated. Both AGCT and GDM groups were found to have similarly higher plasma ADMA levels than control subjects (3.60±1.21; 4.00±1.70; 2.65±0.82 μmol/l, respectively, P=0.001). ADMA was significantly but slightly correlated with insulin sensitivity/resistance indices and moderately correlated with 2-h insulin level. The 2-h insulin value of the OGTT was the independent influencing constant for ADMA (R=0.57, P=0.0001). In conclusion, plasma asymmetric dimethylarginine level was higher in cases with abnormal glucose challenge test but normal OGTT as well as in gestational diabetics, compared to pregnant women with normal glucose tolerance. The elevated ADMA level in pregnant women with carbohydrate intolerance may possibly be due to elevated insulin level.     

Abnormal screening glucose challenge test in pregnancy and future risk of diabetes in young women

Aims Pregnant women commonly undergo screening for gestational diabetes mellitus (GDM) using a 50‐g glucose challenge test (GCT), followed by a diagnostic oral glucose tolerance test (OGTT) in those women in whom the GCT is abnormal. Although it has long been recognized that GDM is associated with subsequent Type 2 diabetes, it has recently emerged that any degree of abnormal antepartum glucose homeostasis predicts an increased risk of postpartum glucose intolerance. Thus, in this context, we sought to determine whether women who have a pregnancy complicated by an abnormal GCT, but who do not have GDM, are at increased risk of subsequent diabetes, compared with their peers with an abnormal GCT. Methods A population‐based, retrospective cohort study was conducted. Women referred for an antepartum OGTT indicative of an abnormal GCT (n = 15 381), but without GDM, were matched (for age, region, socioeconomic status, and year of delivery) with up to four other women without such referral (n = 61 237). The two cohorts were followed over a median 6.4 years for the development of diabetes. Results The rate of incident diabetes was 5.04 cases per 1000 person‐years in the cohort of women who underwent an antepartum OGTT, compared with 1.74 cases per 1000 person‐years in women without an OGTT. The hazard ratio for subsequent diabetes in women with an antepartum OGTT was 2.56 (95% confidence interval 2.28, 2.87) (P < 0.0001). Conclusions Even in the absence of GDM, abnormal screening GCT in pregnancy is associated with an increased future risk of diabetes in young women.     

Gestational diabetes: fasting capillary glucose as a screening test in a multi‐ethnic,high‐risk population

Aims In populations at high risk of gestational diabetes mellitus (GDM), screening every pregnant woman by an oral glucose tolerance test (OGTT) is very demanding. The aim of this study was to determine the value of the fasting capillary glucose (FCG) as a screening test for GDM. Methods FCG was measured by a plasma‐correlated glucometer in 1465 pregnant women who underwent a one‐step diagnostic 75‐g OGTT for universal screening of GDM. Results One hundred and ninety‐six (13.4%) women had GDM as defined by the criteria of the American Diabetes Association. The area under the receiver operating characteristic curve (AUC) of the FCG was 0.83 (95% confidence interval 0.80–0.86). A FCG threshold of 4.7 mmol/l (at an acceptable sensitivity of 86.0%) independently could rule‐out GDM in 731 (49.9%) women, while the FCG could rule‐in GDM (100% specificity) in 16 (1.1%) additional women; therefore, approximately half of the women would not need to continue with the cumbersome OGTT. Conclusions Screening using a FCG significantly reduces the number of OGTTs needed for the diagnosis of GDM. Wider assessment, particularly in low‐risk populations, would confirm the potential value of the FCG as a screening test for GDM.     

Maternal triglyceride levels and newborn weight in pregnant women with normal glucose tolerance.

OBJECTIVE: To determine the predictive value of serum triglyceride levels (TG) for neonatal weight in pregnant women with positive diabetic screening but normal glucose tolerance. RESEARCH DESIGN AND METHODS: We enrolled 180 pregnant Caucasian women with positive diabetic screening. All women underwent a 3-h 100-g oral glucose tolerance test (OGTT) at 27th +/- 4 week of gestation. At the time of OGTT, we measured: fasting plasma glucose, fasting lipids profile and determined ApoE polymorphisms to evaluate the effects on lipid levels. In 83 women with normal glucose tolerance and at term delivery we evaluated the association between maternal serum TG, specific maternal parameters known to affect fetal growth and newborn weight. RESULTS: Based on OGTT, gestational diabetes mellitus (GDM) was diagnosed in 36 women (20%), impaired glucose tolerance (IGT) in 23 (13%), and normal glucose tolerance (NGT) in 121 (67%). Serum TG concentration was significantly higher in women with GDM (2.47 +/- 0.77 mmol/l) as compared with NGT (1.99 +/- 0.64 mmol/l) or IGT (1.98 +/- 0.81 mmol/l) (P < 0.01). ApoE3 allelic frequency was 86%, ApoE2 and ApoE4 were 5 and 9%, respectively. We found no clear-cut association between apoE genotype and serum TG concentration. Macrosomia and LGA newborns were more frequent in IGT than in GDM or NGT (P < 0.01). In the 83 women with positive diabetic screening but normal glucose tolerance who delivered at term, the incidence of LGA infants was significantly higher in those with TG levels higher than the 75th percentile (> 2.30 mmol/l) (21%) than in mothers who had normal TG levels (4.5%) (P < 0.05). Pre-pregnancy BMI (r(2) = 0.067), weight gain during pregnancy (r(2) = 0.062), fasting serum TG (r(2) = 0.09), and 2-h post-OGTT glucose levels (r(2) = 0.044) were all associated with neonatal body weight (all P < 0.05 or less). However, on a multiple regression analysis, only pre-pregnancy BMI (F-test = 7.26, P < 0.01), and fasting serum TG (F-test = 4.07, P < 0.01) were independently associated with birth weight. CONCLUSIONS: Pre-pregnancy BMI and fasting maternal serum TG determined in the last trimester of gestation were independently associated with neonatal birth weight in women with normal glucose tolerance, but positive screening test. TG levels measured in the third trimester of pregnancy are independent of the genetic polymorphism of ApoE.     

Heterogeneity of pregnancy outcomes and risk of LGA neonates in Caucasian females according to IADPSG criteria for gestational diabetes mellitus

ObjectiveThe International Association of Diabetes and Pregnancy Study Group (IADPSG) guidelines for gestational diabetes mellitus (GDM) diagnosis determines that fasting, 1-h and 2-h glucose values may contribute independently to adverse outcomes. However, given the different physiological bases of impaired fasting glucose (IFG) and impaired glucose tolerance (IGT), differences in pregnancy outcomes are to be expected. This study aimed to determine whether classification of GDM women according to glucose homoeostasis results in heterogeneity in maternal and/or fetal outcomes.Material and methodsOf the 75 pregnant women included after a 75-g 2-h OGTT performed between weeks 24–32 of gestation as per WHO criteria, 55 were classified as GDM (16 with IFG and 39 with IGT) according to IADSPG criteria. Their anthropometric and metabolic characteristics were compared with those of non-GDM women with IFG or IGT. Maternal and neonatal outcomes were prospectively recorded for each group.ResultsGDM women with IFG, including isolated IFG and combined IFG + IGT, were significantly heavier, had higher leptin values and were more frequently multiparous than GDM women with isolated IGT. HOMA-IR was significantly higher when fasting glucose was impaired. There were no significant differences in maternal outcomes according to metabolic status. In addition, large for gestational age (LGA) neonates were significantly seen more often in the IFG group. Fasting glucose was significantly associated with LGA independently of BMI and 2-h OGTT glucose. The > 5.1 mmol/L cut-off value for fasting glucose was highly predictive of delivery of LGA infants.ConclusionIFG in GDM women was associated with increases in BMI, fat mass and hepatic insulin resistance. Delivery of LGA neonates was more frequent when fasting glycaemia was increased during the third trimester of pregnancy, and was independent of BMI and 2-h OGTT glucose values.     

Does parity increase insulin resistance during pregnancy?

AIMS: To study the effect of parity on impairment of insulin sensitivity during pregnancy and on the risk of gestational diabetes (GDM). METHODS: We studied the relationship between parity and peripheral insulin sensitivity index (ISI(OGTT)) or GDM in 1880 caucasian women, who underwent a 100-g, 3-h oral glucose tolerance test (OGTT) between the 24th and 28th gestational week and in 75 women who underwent an OGTT in two consecutive pregnancies. A proxy for beta-cell function (basal plasma C peptide/fasting plasma glucose; CP/FPG) was also measured. RESULTS: By univariate analysis parity was related to decreased ISI(OGTT) and to increased CP/FPG in those with parity > 3 and likewise GDM, diagnosed in 124 women (6.58%), was linearly related to parity (P = 0.0034) and strongly age dependent. The relationships between parity and ISI(OGTT), CP/FPG and GDM were no longer significant after adjustment for age, pregestational body mass index (BMI), and weight gain. GDM was significantly related to age and pregestational weight, while ISI(OGTT) and CP/FPG were inversely related to prepregnancy BMI or weight gain. In comparison with the index pregnancy, the subsequent pregnancy was characterized by an increase in actual and prepregnancy BMI, in 2 h area under curve (AUC) glucose and by a decrease in ISI(OGTT) (P = 0.0001). The longer the time interval between pregnancies and the higher the increment in pregestational BMI or in weight gain during the pregnancy, the greater were the ISI(OGTT) decrease and 2-h AUC glucose increase. CONCLUSIONS: Parity is not directly linked to insulin sensitivity deterioration, to CP/FPG increase during pregnancy, or to GDM appearance, although it is linked through the mediation of progressive ageing and weight gain either before or during pregnancy, when there is a sufficiently long time interval between pregnancies.     

Can plasma glucose and HbA1c predict fetal growth in mothers with different glucose tolerance levels?

To assess whether HbA1c and plasma glucose predicts abnormal fetal growth, 758 pregnant women attending 5 Diabetic Centers were screened for gestational diabetes mellitus (GDM). On glucose challenge (GCT) at 24-27 weeks of gestation (g.w.), negative cases formed the normal control group (N1). Positive cases took an oral glucose tolerance test (OGTT): those found negative were classed as false positives screening test (N2); if they had an OGTT result at least as high as their normal glucose levels, they were classed as having one abnormal glucose value (OAV) at OGTT; two values as GDM. HbA1c was assayed on the day of GCT. We considered fetal macrosomia, large for gestational age (LGA), ponderal index and mean growth percentile. Mean age, pre-pregnancy BMI, fasting plasma glucose (FPG) and HbA1c were progressively higher from N1 to GDM patients. The newborn of N2 mothers were heavier than those with N1 or GDM. The mean growth percentile was significantly higher in N2 than in N1. More LGA babies were born to OAV than to N1 or N2 women. Macrosomia and ponderal index did not differ significantly in the four groups. At logistic regression only plasma glucose at GCT could predict LGA babies and a ponderal index above 2.85. At risk analysis, GDM and OAV significantly predicted LGA babies, and GDM a ponderal index >2.85. In conclusion, FPG at GCT could predict fetal overgrowth and plasma glucose >85mg/dl doubles the risk of LGA infants. HbA1c at 24-27g.w. does not predict fetal overgrowth. Mild alterations in glucose tolerance correlate with fetal overgrowth and needs monitoring and treatment.     

Gestational diabetes: utility of fasting plasma glucose as a screening test depends on the diagnostic criteria.

AIMS: To demonstrate the effect of diagnostic criteria, as defined by four international expert panels, on the usefulness of fasting plasma glucose (FPG) as a screening test for gestational diabetes mellitus (GDM). METHODS: We tested 4602 pregnant women using a 75-g oral glucose tolerance test (OGTT) for universal GDM screening. The area under the receiver operating characteristic curve (AUC) was used to determine the FPG performance to detect GDM by the criteria of the American Diabetes Association (ADA), the Australasian Diabetes in Pregnancy Society, the European Association for the Study of Diabetes, and the World Health Organization (WHO). RESULTS: By applying ADA, Australasian, European and WHO criteria, respectively, the FPG: (i) AUC (95% CI) was 0.882 (0.866-0.897), 0.830 (0.809-0.852), 0.808 (0.791-0.825) and 0.690 (0.670-0.710); (ii) independently could 'rule-in' GDM (with 100% specificity) in 74 (10.9%), 620 (53.5%), 252 (45.3%) and 74 (7.6%) women; (iii) independently could 'rule-out' GDM in an additional 2864 (62.2%), 928 (20.2%), 1510 (32.8%) and 1171 (25.4%) women, at FPG thresholds (with 85% sensitivity); (iv) false-positive rate (FPR) was 29.4, 75.5, 63.8 and 71.2%, at these thresholds. CONCLUSIONS: The value of the FPG as a screening test for GDM is highly dependent on the diagnostic criteria. The performance is excellent with the ADA criteria. With the other criteria, the high FPR (poor specificity) would limit its utility as a screening test. Regardless of the criteria used, initial testing by FPG can significantly decrease the number of cumbersome OGTTs needed for the diagnosis of GDM.     

Screening tests for gestational diabetes in Japan in the 1st and 2nd trimester of pregnancy

The objective of this study was to investigate the utility and characteristics of various screening procedures for gestational diabetes mellitus (GDM) in Japan during the first trimester and between 24 and 28 weeks of pregnancy. The subjects were 749 pregnant women who came to our hospitals. A 50-g oral glucose challenge test (GCT), casual plasma glucose measurements, fasting blood glucose measurements, and glycosylated hemoglobin measurements were performed in the first trimester. Subjects with no abnormalities were tested again at 24-28 weeks of gestation. Of the 749 subjects, 22 (2.9%) tested positive for GDM. Of those 22 patients, 14 were diagnosed with GDM in the first trimester (63.6%) and eight in the second trimester (36.4%). This finding suggests the importance of screening for glucose intolerance in the first trimester. Furthermore, it appears that the GCT has the most utility for GDM screening; the other screening methods tested were not as useful because of their low sensitivity, particularly in the second trimester.     

Prevalence of gestational diabetes mellitus in Kashmiri women from the Indian subcontinent

This prospective study was carried out to determine the prevalence of gestational diabetes mellitus (GDM) in Kashmiri women and to assess the effect of various demographic factors. Two thousand pregnant women (divided into groups A and B, being the first and last 1000 consecutive women) attending various antenatal clinics in six districts of Kashmir valley were screened for GDM by 1 h 50 g oral glucose challenge test. Four hundred and fourteen (20.8%) women (216 from group A and 198 from group B) had an abnormal screening test and proceeded to oral glucose tolerance testing. Women from group A had a 3 h 100 gram oral glucose tolerance test (OGTT) and GDM was as classified by Carpenter and Coustan. A 2 h 75 g OGTT was performed on group B subjects and WHO criteria applied for diagnosis of GDM. The overall prevalence of GDM was 3.8% (3.1% in group A versus 4.4% in group B-P-value 0.071). GDM prevalence steadily increased with age (from 1.7% in women below 25 years to 18% in women 35 years or older). GDM occurred more frequently in women who were residing in urban areas, had borne three or more children, had history of abortion(s) or GDM during previous pregnancies, had given birth to a macrosomic baby, or had a family history of diabetes mellitus. Women with obesity, hypertension, osmotic symptoms, proteinuria or hydramnios had a higher prevalence of GDM.     

Hypertensive disorders in Japanese women with gestational glucose intolerance

We investigated the relationship between gestational glucose intolerance and the development of pregnancy-induced hypertension including gestational hypertension (GH) and preeclampsia. Consecutive Japanese women with singleton pregnancies underwent a standard 1h, 50g oral glucose challenge test (GCT) at 24-27 weeks of gestation, followed by a 75g, 2h oral glucose tolerance test (OGTT) if the GCT result exceeded 130mg/dl. Using criteria of the Japan Society of Obstetrics and Gynecology, gestational diabetes mellitus (GDM) was defined by two or more abnormal OGTT values and mild glucose intolerance by one abnormal value. The normal glucose tolerance group included women with GCT results below 130mg/dl or normal OGTT values. GH was defined as blood pressure of at least 140/90mmHg occurring for the first time after mid-pregnancy, without proteinuria. Preeclampsia was determined as GH with proteinuria. Of 2651 consecutive patients, 49 women were found to have GDM, and 139 showed mild glucose intolerance. Sixty patients showed GH, and 58 developed preeclampsia. The frequency of GH in mild glucose intolerance or GDM was 5.8% or 8.2%, respectively, significantly greater than in normal glucose tolerance (P<0.01). Incidence of preeclampsia was not significantly increased in women with mild glucose intolerance or GDM (2.2% or 4.1%, respectively, compared to those with normal glucose tolerance). Japanese women with gestational glucose intolerance therefore have an increased risk of developing GH.