Glucose Challenge Test Results Research Articles

Comparison the Carpenter and Coustan thresholds with the new thresholds obtained from Thai pregnant women for the diagnosis of gestational diabetes

Aims To determine the threshold of plasma glucose levels calculated from the mean + 2SDs for diagnosing gestational diabetes mellitus (GDM) in Thai women. Methods Thai pregnant women without pre-existing diabetes were invited into the study. A 100-g oral glucose tolerance test (OGTT) was performed in all participants during their second or third trimesters, regardless of the results of 50-g glucose challenge test. Results Seven hundred and ninety seven women with singleton pregnancy participated in the study. The distribution of 1-, 2-, and 3-h plasma glucose levels of the 100-g OGTT was Gaussian. The rounded cut-off point values calculated from the mean + 2SDs were 90, 195, 170, and 155 mg/dl, respectively for fasting, 1-, 2-, and 3-h plasma glucose. With the Carpenter and Coustan thresholds, 52 women (6.5%, 95%CI 4.9–8.5%) were diagnosed as GDM. Of these, when tested with the new thresholds, 30 had normal glucose tolerance and 22 were diagnosed as GDM. Conclusion By using mean + 2SDs of plasma glucose levels of the 100-g OGTT as the threshold for diagnosing GDM, the thresholds at 1, 2, and 3 h obtained from Thai women were 15 mg/dl higher than those of the Carpenter and Coustan thresholds.

Maternal mid-pregnancy serum triglyceride levels and neonatal birth weight

Although disturbances in maternal glucose metabolism and resultant fetal hyperinsulinemia are known to significantly impact fetal overgrowth, it has been suggested that other fuels such as lipids and amino acids may be the determinants of fetal growth in nondiabetics. Maternal serum lipid levels increase in mid to late pregnancy; and in women with gestational diabetes, elevated triglycerides were significantly associated with birth weight corrected for gestational age. Although the role of maternal hyperlipidemia in fetal growth is not known, maternal fasting serum triglyceride levels at 24 to 32 weeks of Pregnancy were shown to be significantly and positively associated with neonatal weight at term,independent of maternal prepregnancy obesity, weight gain during pregnancy, or mid-pregnancy plasma glucose levels (either fasting or postprandial) in Japanese and white women. The aim of the present study was to determine the relationship between maternal mid-pregnancy serum lipid levels and neonatal birth weight in our region. Fasting levels of serum triglycerides and total cholesterol were evaluated in 108 consenting consecutive women who attended for prenatal care with a singleton pregnancy between 24 to 34 weeks and who had abnormal results on the glucose challenge test (plasma glucoseN140 mg/dL) and normal results from the oral 100 g 3-hour glucose tolerance test. Women with antiphospholipid antibody syndrome, hypertension, or thyroid disorder were excluded. The relationship between mid-pregnancy triglyceride and total cholesterol values and neonatal birth weight was determined according to fasting glucose, body mass index (BMI, calculated as weight in kilograms divided by height in meters squared) and pregnancy weight gain—with 95 mg/dL, 25, and 10 kg as the cut-off values, respectively. The relative risk of having heavier babiesweighing 3.5 kg or greater was 2 (95% CI, 0.9–4.2) for women with hypertriglyceridemia and 2.6 (95% CI, 0.78–8.4) when controlled for fasting glucose, BMI, and pregnancy weight gain. When studied together, the combination of hypertriglyceridemia, fasting hyperglycemia, and higher BMI was a significant predictor of heavier neonates. It is important to note that the higher relative risk for heavier babies in women with hypertriglyceridemia persisted even when the variables such as greater BMI, greater pregnancy weight gain, and hyperglycemia were accounted for. With a combination of greater BMI and fasting hyperglycemia, women with hypertriglyceridemia had a much higher relative risk for heavier babies (RR 9.7; 95% CI, 1.7–62.6).

830: Adverse neonatal outcomes correlate with extremely elevated oral glucose challenge test results (OGCT > 200 mg/dl) despite adequate glycemic control

830: Adverse neonatal outcomes correlate with extremely elevated oral glucose challenge test results (OGCT > 200 mg/dl) despite adequate glycemic control

Circulating Pro- and Anti-inflammatory Cytokines in Polish Women with Gestational Diabetes

In this study we measured serum concentrations of proinflammatory interleukin-6, interleukin-8, and interleukin-18 as well as anti-inflammatory interleukin-10 in 30 pregnant women with normal glucose tolerance, in 32 women with abnormal results of a 50-g glucose challenge test, and in 57 patients with gestational diabetes mellitus. Patients with gestational diabetes had significantly higher IL-6 (median 1.0 [0.7-1.5] vs. 0.7 [0.4-0.8] pg/ml, p=0.001), IL-8 (2.1 [1.1-4.2] pg/ml vs. 0.7 [0.4-0.9] pg/ml, p<0.0001), and IL-18 (249.3 [188.5-318.7] pg/ml vs. 186.7 [139.9-243.9] pg/ml, p=0.005) as well as lower IL-10 levels than healthy pregnant women (0.6 [0.5-1.5] pg/ml vs. 2.9 [1.8-3.2] pg/ml, p<0.0001). After adjusting for glucose, insulin, and BMI values, the differences in IL-8 and IL-18 became insignificant, whereas the differences in IL-6 and IL-10 levels remained highly significant (p<0.0001). The subjects with abnormal glucose challenge test results had higher IL-6 levels (0.9 [0.7-1.3] pg/ml, p=0.005) and similar levels of other cytokines as compared with the women with normal glucose tolerance. Our results suggest an impaired balance between circulating pro- and anti-inflammatory cytokines in patients with gestational diabetes; however, a significant contribution of maternal obesity to the increased levels of IL-8 and IL-18 should be underlined.

Glucose Challenge Test Does not Predict Gestational Diabetes Mellitus

It is widely acknowledged that identification and treatment of gestational diabetes mellitus (GDM) results in better maternal and neonatal outcomes. However, the utility of the glucose challenge test (GCT) remains controversial regarding the diagnostic approach and decision making. We performed a retrospective analysis on the database of our Laboratory Information System to retrieve results of GCT and oral glucose tolerance test (OGTT), which were performed on consecutive female outpatients referred by the gynecologists over the last 3 years. Cumulative results for GCT and OGTT were retrieved for 724 female outpatients and screening test was abnormal in 114 of them. This group was classified in terms of normal glucose tolerance (NGT), one abnormal value for the 100-g-3h OGTT (OAV) and GDM. GDM was diagnosed only in 34 subjects (4.7%). No statistically significant differences were observed in the basal plasma glucose and 1-h GCT values among groups. Multivariable logistic regression analysis demonstrated that age, OGTT values >or=180 mg/dL at 1 hour and OGTT values >or=155 mg/dL at 2 hours, but not GCT values, were independent predictors for GDM (p=0.048, p=0.012 and p<0.001, respectively). Results of our retrospective analysis on an unselected population are consistent with the hypothesis that GCT is not predictive of GDM and its diagnostic significance remains questionable.

The impact of maternal age, body mass index and maternal weight gain on the glucose challenge test in pregnancy

Objective. The aim of this study was to determine whether maternal age, prepregnancy and mid-trimester body mass index (BMI), or excessive mid-pregnancy weight gain predict abnormal glucose challenge test (GCT) results.Methods. A retrospective chart review of 75 consecutive singleton pregnancies was performed. Patients were screened at 24–28 weeks of gestation with a 50-g oral GCT. Prepregnancy BMI and pregnancy weight gain up to the time of GCT testing, as well as other demographic data, were recorded. Statistical analysis included regression analysis and Student's t-test, receiver–operator characteristic curve and multivariate logistic regression.Results. Maternal age and prepregnancy and mid-trimester BMI were significantly higher in women with an abnormal GCT (p < 0.05). A direct correlation was found between these parameters and GCT results (R2 = 0.08, R2 = 0.102 and R2 = 0.116, respectively; p < 0.05). Mid-trimester maternal BMI of ≥30 kg/m2 and maternal age ≥32 years are the optimal predictors of abnormal GCT results.Conclusions. Mid-trimester maternal BMI of ≥30 kg/m2 and maternal age ≥32 years are useful predictors of abnormal GCT results. We suggest that these factors should also be considered when selective screening for gestational diabetes mellitus is practiced.

Glucose challenge test: Screening threshold for gestational diabetes mellitus and associated outcomes

Objective. To examine whether women with an 1-hour 50-g glucose challenge test (GCT) for gestational diabetes mellitus (GDM) between 120 and 140 mg/dL and ≥140 mg/dL are at risk of perinatal complications.Study design. A retrospective cohort study of women with singleton pregnancies screened for GDM between 1988 and 2001 with a 1-hour 50-g GCT. Values of GCT were stratified into four subgroups: <120, 120–129, 130–139, and ≥140 mg/dL. Perinatal outcomes were compared using the Chi-square test and multivariable logistic regression analysis.Results. There were 13 901 women meeting the study criteria. Compared to women with a GCT of <120 mg/dL, women with a GCT of 130–139 mg/dL and ≥140 mg/dL were more likely to have preeclampsia and operative vaginal or cesarean deliveries. Neonates born to women with a GCT of 130–139 mg/dL also had higher odds of having a 5-minute Apgar score <7 (odds ratio (OR) = 1.51, 95% confidence interval (CI) 1.01–2.29), shoulder dystocia (OR = 2.02, 95% CI 1.16–2.55), birth trauma (OR = 1.47, 95% CI 1.06–2.02), and composite morbidity (OR = 1.25, 95% CI 1.03–1.51). Women with a GCT of ≥140 mg/dL had higher odds of macrosomia (OR = 1.32, 95% CI 1.13–1.54) and shoulder dystocia (OR = 1.68, 95% CI 1.11–2.55).Conclusion. Women with GCT results of 130–139 mg/dL appear to be at increased risk for perinatal morbidity. Thus, utilizing a diagnostic test in women with a GCT above 130 mg/dL should be considered.

Value of fructosamine measurement in pregnant women with abnormal glucose tolerance

The concentration of serum fructosamine is correlated with plasma glucose level. The aim of this study was to determine whether the level of serum fructosamine can be diagnostic for abnormal glucose tolerance in pregnant women. Serum samples were collected from 161 pregnant women between November 2004 and April 2005. The women were divided into three groups according to the gestational age (16 - 20 weeks group, 56 patients; 28 - 34 weeks group, 72; and 37 - 41 weeks group, 33). Each group was subdivided into normal and abnormal glucose tolerance subgroups. The levels of serum fructosamine were measured. Differences among the groups were assessed by ANOVA and Student-Newman-Keuls test. Correlations between the level of fructosamine and other variables including the results of glucose challenge test (GCT), oral glucose tolerance test (OGTT), and glycosylated hemoglobin (HbA1c) test, and infant's birth weight were analyzed by Pearson correlation. The level of serum fructosamine decreased with gestational age [(223.25 +/- 48.90) micromol/L, (98.44 +/- 29.57) micromol/L, and (53.99 +/- 29.94) micromol/L, respectively. P < 0.05]. It was higher in women with abnormal glucose tolerance than that in women with normal glucose tolerance, however, the difference reached statistical significance only in the 28 - 34 weeks group (P < 0.05). In this group, the level of serum fructosamine correlated positively with the GCT result (r = 0.28, P < 0.05). No correlation was found between fructosamine level and OGTT result, HbA1c level, or neonatal weight. Fructosamine can be used to monitor the glucose level of pregnant women with abnormal glucose tolerance, and to identify the patients at high risk of abnormal glucose tolerance, but can not be used to predict gestational diabetes mellitus (GDM) in early stage of pregnancy.

Reference Intervals for Hemoglobin A1c in Pregnant Women: Data from an Italian Multicenter Study

The reference intervals for hemoglobin A1c (Hb A1c) in pregnant women without diabetes are not well defined, and few examples of reference intervals established by networks of different laboratories are available. Five Italian Diabetic Care Units were involved in the study. Data were collected from 445 pregnant women without diabetes, selected on the basis of glucose challenge test results, and from 384 nonpregnant control women. The Hb A1c measurements were performed with HPLC systems aligned to the Diabetes Control and Complications Trial. Plasma glucose measurements were also performed locally. Both Hb A1c and glucose measurements were harmonized by running appropriate external quality assessment schemes. The reference intervals were calculated in terms of nonparametric 2.5th to 97.5th percentiles with 0.90 confidence intervals. The Hb A1c measurements were reproducible (CV = 2.0%) and accurate [mean (SE) difference from the target values, -0.10 (0.06)%]. Glucose measurements were also reproducible (mean CV = 3.2%) and accurate [difference from the target values, -0.01 (0.04) mmol/L]. To calculate common reference intervals, we merged the data collected in the different centers. The Hb A1c reference intervals were 4.0%-5.5% for pregnant nondiabetic women and 4.8%-6.2% for nonpregnant controls. Healthy pregnant women have lower Hb A1c concentrations than nonpregnant women. The reference intervals for Hb A1c in pregnant women should therefore be lower than those currently in use.

Characteristics of patients with abnormal glucose challenge test and normal oral glucose tolerance test results: Comparison with normal and gestational diabetic patients

The purpose of this study was to evaluate the characteristics and outcomes of patients who had abnormal glucose challenge test results and subsequent normal oral glucose tolerance test results and to assess whether such patients are at a greater risk than normal pregnant patients for adverse perinatal outcome. In this retrospective cohort study that was conducted between June and December 2003, 101 pregnant women (group A) had an abnormal glucose challenge test result and a normal oral glucose tolerance test result. Data were also collected on 2 control groups: 100 pregnant women with normal glucose challenge test results (group B) and all 76 pregnant women who were diagnosed with gestational diabetes mellitus during this period of time (group C). Patients with multiple pregnancies, chronic hypertension, pregestational diabetes mellitus, or any other maternal or fetal problems that were diagnosed before 24 weeks (when the glucose challenge test was performed) were excluded from the study groups. The following data were collected and analyzed: maternal age, maternal weight and height, parity and gravidity, diabetes mellitus in first-degree relatives, medical and obstetric history, ethnicity, complications during the third trimester of pregnancy, birth weight, gestational age at delivery, mode of delivery, Apgar scores, cord blood gas results, maternal complications of labor and during the postpartum period, and infant admission to the neonatal intensive care unit. For comparison between groups, we used the Student t test, 1-way analysis of variance, the chi-square test, and stepwise logistic regression. Patients in groups A and C were significantly older compared with group B (29.2 +/- 5.6 years and 30.4 +/- 5.5 years, respectively, vs 24.8 +/- 5.5 years; P < .01), had a lesser rate of primiparity (48% and 31%, respectively, vs 24%; P < .05), had greater body mass index (30.8 +/- 5 kg/m2 and 31.3 +/- 6 kg/m2, respectively, vs 29.2 +/- 4.4 kg/m2; P < .01), had a greater rate of previous gestational diabetes mellitus (6% and 20%, respectively, vs 0%; P < .05), and had a greater rate of first-degree family members with diabetes mellitus (21% and 21%, respectively, vs 3%; P < .01). None of the outcome parameters was statistically significant when group A was compared with group B. Patients with an abnormal glucose challenge test result and a subsequent normal oral glucose tolerance test result have different maternal characteristics and backgrounds compared with patients in whom both test results are normal, yet both groups have normal outcomes. We should continue to consider patients who have an abnormal glucose challenge test result and subsequent normal oral glucose tolerance test result as low-risk; however, these findings may represent an indication of an increased likelihood for the development of overt diabetes mellitus later in life.

Impaired Glucose Tolerance of Pregnancy Is a Heterogeneous Metabolic Disorder as Defined by the Glycemic Response to the Oral Glucose Tolerance Test

OBJECTIVE—Gestational diabetes mellitus (GDM), defined by two abnormal glucose values on a 3-h oral glucose tolerance test (OGTT), is associated with insulin resistance and a low serum concentration of adiponectin. The metabolic implications of impaired glucose tolerance (IGT) of pregnancy (i.e., a single abnormal value on an OGTT), however, are not well established. We sought to evaluate the metabolic phenotype of pregnant women with IGT in relation to the timing of their isolated hyperglycemia. RESEARCH DESIGN AND METHODS—A cross-sectional study was performed in pregnant women undergoing a 3-h, 100-g OGTT. The OGTT stratified participants into four groups: 1) GDM (n = 48), 2) 1-h IGT (single elevated value at 1 h) (n = 15), 3) 2-h/3-h IGT (single elevated value at either 2 or 3 h) (n = 23), and 4) normal glucose tolerance (NGT) (n = 93). Insulin sensitivity was measured by the validated insulin sensitivity index (ISOGTT) of Matsuda and DeFronzo. RESULTS—Measures of severity of glycemia (fasting glucose, area under the glucose curve from the OGTT, and glucose challenge test result) were highest in the GDM group, followed by the 1-h IGT, 2-h/3-h IGT, and NGT groups, respectively (each trend P &amp;lt; 0.0001). Consistent with this finding, ISOGTT was highest in the NGT group (5.1), followed by the 2-h/3-h IGT (4.6), 1-h IGT (3.8), and GDM (3.2) groups (trend P &amp;lt; 0.0001). Furthermore, on multiple linear regression analysis of ISOGTT, both GDM and 1-h IGT were independently associated with reduced insulin sensitivity (whereas 2-h/3-h IGT was not). Mean adjusted adiponectin was highest in the NGT group (15.7 μg/ml), followed by the 2-h/3-h IGT (15.6 μg/ml), 1-h IGT (13.7 μg/ml), and GDM (12.0 μg/ml) groups (trend P = 0.0024). CONCLUSIONS—The metabolic implications of IGT in pregnancy vary in relation to the timing of the abnormal glucose value from the diagnostic OGTT. The metabolic phenotype associated with 1-h IGT resembles that of GDM, whereas the phenotype associated with 2-h/3-h IGT exhibits similarity to that of NGT.

Impaired Glucose Tolerance of Pregnancy Is a Heterogeneous Metabolic Disorder as Defined by the Glycemic Response to the Oral Glucose Tolerance Test

Gestational diabetes mellitus (GDM), defined by two abnormal glucose values on a 3-h oral glucose tolerance test (OGTT), is associated with insulin resistance and a low serum concentration of adiponectin. The metabolic implications of impaired glucose tolerance (IGT) of pregnancy (i.e., a single abnormal value on an OGTT), however, are not well established. We sought to evaluate the metabolic phenotype of pregnant women with IGT in relation to the timing of their isolated hyperglycemia. A cross-sectional study was performed in pregnant women undergoing a 3-h, 100-g OGTT. The OGTT stratified participants into four groups: 1) GDM (n = 48), 2) 1-h IGT (single elevated value at 1 h) (n = 15), 3) 2-h/3-h IGT (single elevated value at either 2 or 3 h) (n = 23), and 4) normal glucose tolerance (NGT) (n = 93). Insulin sensitivity was measured by the validated insulin sensitivity index (IS(OGTT)) of Matsuda and DeFronzo. Measures of severity of glycemia (fasting glucose, area under the glucose curve from the OGTT, and glucose challenge test result) were highest in the GDM group, followed by the 1-h IGT, 2-h/3-h IGT, and NGT groups, respectively (each trend P < 0.0001). Consistent with this finding, IS(OGTT) was highest in the NGT group (5.1), followed by the 2-h/3-h IGT (4.6), 1-h IGT (3.8), and GDM (3.2) groups (trend P < 0.0001). Furthermore, on multiple linear regression analysis of IS(OGTT), both GDM and 1-h IGT were independently associated with reduced insulin sensitivity (whereas 2-h/3-h IGT was not). Mean adjusted adiponectin was highest in the NGT group (15.7 microg/ml), followed by the 2-h/3-h IGT (15.6 microg/ml), 1-h IGT (13.7 microg/ml), and GDM (12.0 microg/ml) groups (trend P = 0.0024). The metabolic implications of IGT in pregnancy vary in relation to the timing of the abnormal glucose value from the diagnostic OGTT. The metabolic phenotype associated with 1-h IGT resembles that of GDM, whereas the phenotype associated with 2-h/3-h IGT exhibits similarity to that of NGT.

The association between glucose challenge test, obesity and pregnancy outcome in 6390 non-diabetic women

Objective: To evaluate the association between obesity, glucose challenge test (GCT) and pregnancy outcome.Methods: A prospective cohort study of 6854 consecutive gravid patients screened for gestational diabetes (GDM) using 50-gram GCT, at 24–28 weeks' gestation was performed. A screening value ⩾ 130 mg/dl was followed by 100 gr oral GTT. Patients who were diagnosed with GDM were excluded. For purpose of analysis patients were categorized by prepregnancy BMI and by different GCT thresholds. Maternal outcome was defined by rate of preeclampsia, gestational age at delivery, cesarean section (CS) rate and the need for labor induction. Neonatal outcome was defined by fetal size (macrosomia/LGA), arterial cord pH, respiratory complications and neonatal intensive care unit (NICU) admission.Results: Overall, a positive GCT result (GCT ⩾ 130 mg/dl) was identified in 2541/6854 (37%) women. GDM was further diagnosed in 464/6854 (6.8%) of subjects. In both groups of screening results ( > 130 mg/dl and < 130 mg/dl), the obese women were significantly older, gained more weight during pregnancy and had a lower rate of nulliparity in comparison to the non obese women. The obese women had higher rates of macrosomia, LGA and induction of labor. No difference was found in mean birth weight, the total rate of cesarean section, preterm delivery, 5 minute Apgar score ⩽ 7, mean arterial cord pH, NICU admission and a need for respiratory support in comparison to non obese women in both groups of screening results. A gradual increase in the rate of macrosomia, LGA and cesarean section was identified in both obese and non-obese women in relation to increasing GCT severity categories.Conclusion: Fetal size and cesarean section rate are associated with the degree of carbohydrate intolerance (screening results). Furthermore, obesity remains the main contributor impacting fetal size.

One Hour versus Two Hours Postprandial Glucose Measurement in Gestational Diabetes: A Prospective Study

To compare the rate of adverse perinatal outcomes among women with gestational diabetes mellitus (GDM), monitored by 1 versus 2 hour-postprandial glucose (PPG) measurements. A total of 112 women diagnosed with GDM, by the criteria of Carpenter-Coustan, were included in the study population. Women were recruited from two different treatment settings, but were managed by the same team of health-care professionals using a standardized protocol. Allocation to treatment group was based on treatment setting. Glucose levels were measured fasting, and either 1 hour (1-hour monitoring group-target values <140 mg/dl) or 2 hours (2-hour monitoring group-target values <120 mg/dl) postprandially. Demographic data and perinatal outcomes were collected from their medical records. In all, 66 women were assigned to 1-hour monitoring group (1 h-PPG) and 46 women to 2-hour monitoring group (2 h-PPG). There were no differences in parity, family history of diabetes, rate of GDM in previous pregnancies, weight gain, pregestational BMI and 50-g-glucose challenge test (GCT) and 100-g oral glucose challenge test (OGTT) results. As expected, there was a significant difference in mean blood glucose levels between the two groups (108.1+/-19.2 and 94.9+/-21.2 mg/dl, 1- and 2 hours, respectively, p<0.0001); however, HbA1C levels were similar in the two groups. Perinatal outcomes were defined as gestational week at delivery; fetal weight (3325+/-471 vs 3309+/-608 g, respectively) and percentile (47.2+/-27 vs 49.6+/-30, respectively), and were similar for both groups. Insulin therapy was initiated more frequently in 2-hour monitoring group (28 and 40% of women in groups 1 and 2, respectively; p<0.05). Rates of macrosomia (7.5 versus 10.6%), large for gestational age (7.4 versus 15.2%), and delivery by cesarean section (24 versus 30%) were increased in group 2 (2 h-PPG) but these differences did not reach statistical significance. These data suggest that diet control in women with GDM managed by 1-hour PPG measurements is associated with a decreased rate of insulin therapy. However, neonatal and obstetrical outcomes are not determined by the timing of their glucose determinations.

Glucose screening in Mexican-American women.

We sought to describe the predictive value for gestational diabetes mellitus (GDM) using different glucose challenge test thresholds in Mexican-American women. A prospective population-based study of 6,857 gravid women, who were tested with a 50-g glucose challenge test at 24-28 weeks of gestation, was performed. A screening value of 130 mg/dL or greater was followed by a 3-hour, 100-g oral glucose tolerance test. Gestational diabetes mellitus was diagnosed by 2 or more abnormal values using the Carpenter and Coustan criteria. For purpose of analysis, GDM diagnosis was categorized with glucose challenge test values in 10-mg/dL increments. A comparison between Carpenter-Coustan and the National Diabetic Data Group criteria for GDM diagnosis was performed for each glucose challenge test threshold category. Sensitivity and specificity for GDM diagnosis were further calculated for different glucose challenge test thresholds (130, 135, and 140 mg/dL). Overall, GDM was diagnosed in 469 of 6,857 (6.8%) women, and one abnormal oral glucose tolerance test value was tested in 351 of 6,857 women (5.1%). Normal glucose challenge test results (threshold less than 130 mg/dL) were obtained in 4,316 of 6,857 women. An elevated glucose challenge test value increases the risk of GDM, but even in high glucose challenge test thresholds (more than 180 mg/dL), the predictive value for GDM was only 50%. The sensitivity and specificity for GDM diagnosis using 3 different glucose challenge test thresholds were as follows: threshold 130 mg/dL or more: 97% and 63%; threshold 135 mg/dL or more: 91% and 73%; and threshold 140 mg/dL or more: 85% and 78%, respectively. Data suggests that an elevated glucose challenge test level cannot be used as a single diagnostic tool for GDM even in high test thresholds. A threshold of 130 mg/dL may be recommended as a screening threshold for GDM in Mexican-American women. II-3

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.

Clinical predictors for a high risk for the development of diabetes mellitus in the early puerperium in women with recent gestational diabetes mellitus

Objective: The purpose of this study was to identify which maternal, antepartum, or neonatal clinical parameters were predictive for a high risk of diabetes mellitus in the puerperium in women with recent gestational diabetes mellitus and to calculate the associated diabetes mellitus rates and odds ratios. Study design: One thousand six hundred thirty-six women underwent an oral glucose tolerance test within 1 to 4 months of delivery. Demographic, historic, and antenatal glycemic parameters and neonatal outcome parameters were tested by univariate and multivariate logistic regression for risk of postpartum diabetes mellitus. Continuous variables were divided into quartiles that compared the upper to lower quartile adjusted odds ratio and prevalence of diabetes mellitus. Results: Postpartum diabetes mellitus was diagnosed in 230 women (14.1%) according to the American Diabetes Association criteria (1997). No maternal demographic or neonatal parameters were significantly associated with diabetes mellitus. The final model of independent predictors in decreasing significance included the highest fasting plasma glucose level during pregnancy, any fasting plasma glucose level of ≥105 mg/dL (class A2), the area under the curve of pregnancy oral glucose tolerance test, gestational age at diagnosis, previous gestational diabetes mellitus history, and 50-g glucose challenge test results. The fasting plasma glucose level was the best discriminator, with a 21-fold (95% CI, 4.6-96.3) increased odds ratio comparing the 4th quartile (fasting plasma glucose level, >121 mg/dL; diabetes mellitus rate, 36.7%) to 1st quartile (fasting plasma glucose level, <95 mg/dL; diabetes mellitus rate, 0.5%). The presence of previous gestational diabetes mellitus or current class A2 gestational diabetes mellitus approximately doubled the odds ratio for diabetes mellitus. The odds ratio increased 3- to 4-fold when the area under the curve was ≥33.36 min · g/dL (4th quartile) or the glucose challenge test was ≥155 mg/dL (2nd–4th quartiles) and decreased >50% if gestational diabetes mellitus was diagnosed at >27 weeks (3rd-4th quartile). Conclusion: During pregnancy, the highest fasting glucose level, followed by the severity of glucose intolerance, and earlier gestational diabetes mellitus diagnosis were the best predictors for postpartum diabetes mellitus. Diabetic education should begin during pregnancy, especially for women who are identified to be at a high risk when they are highly motivated and under medical care. (Am J Obstet Gynecol 2002;186:751-6.)

Screening for gestational diabetes mellitus in northeastern Turkey (Trabzon City).

The purposes of this study were to determine the prevalence of gestational diabetes mellitus (GDM) in Trabzon city of Turkey and to identify appropriate risk factors for gestational diabetes in pregnant mothers. Eight hundred and seven adult pregnant women were screened for GDM with a 1-hour, 50 g oral glucose challenge test (GCT). Three-hour, 100 g oral glucose tolerance tests (GTTs) were performed on screen-positive women. Of the 807 pregnancies screened, 59 (7.3%) had an initial oral GCT result of > or = 140 mg/dl. Diagnostic testing with the oral GTT was performed on the 59 screen-positive gravid women. Of those tested, 10 were diagnosed with GDM on the basis of greater > or = 2 criteria over 3 hours, for a prevalence of 1.23%. Significant associations were found between age, body mass index (BMI) and GDM positivity (p < 0.01 and p < 0.05; respectively). The prevalence of GDM was associated with diastolic blood pressure (DBP) and weeks' gestation (p < 0.05). There was no significant association between increased BMI, systolic blood pressure, number of pregnancies and GDM positivity. In addition, the birth weights of the babies born to mothers with GDM were significantly higher than those of the non-diabetic healthy mothers' babies (p < 0.001). The prevalence of GDM in a Turkish population was low. The prevalence of GDM showed an increase with the ages of pregnant women, gestational age and DBP. This study demonstrates that the universal screening for GDM is not mandatory in our pregnant population. The cost of universal screening may be prohibitive in our population. Large prospective studies are needed to better analyze outcome data and efficacy of screening in adult pregnancies.

Serum chromium does not predict glucose tolerance in late pregnancy

Chromium is an essential element in human nutrition. Serum concentrations of chromium are not well characterized during pregnancy or in gestational diabetes mellitus. The objective of this study was to determine whether low plasma chromium concentrations (< or =3 nmol/L) are associated with altered glucose, insulin, or lipid concentrations during pregnancy. The study was conducted prospectively and took place at the medical obstetric clinic of a tertiary referral hospital. Seventy-nine women with abnormal results of a 50-g glucose challenge test in the third trimester of pregnancy were studied. All women had a formal 75-g oral-glucose-tolerance test, and fasting insulin, lipid, and chromium concentrations were determined. Chromium was measured by graphite furnace atomic absorption spectrometry. The median chromium concentration was 2 nmol/L (95% CI: 0, 12). There were no significant differences in age, plasma glucose, insulin, lipids, calculated insulin resistance, or calculated ss cell function between women with normal and those with abnormal (< or =3 nmol/L) chromium concentrations. Plasma chromium during pregnancy does not correlate with glucose intolerance, insulin resistance, or serum lipids. Plasma chromium concentrations may not accurately reflect tissue stores of chromium. Several trials showed a beneficial effect of chromium supplementation on glucose tolerance, insulin, and lipids. A method for assessing body chromium stores is required to allow further study.

Adverse effects of screening for gestational diabetes: a prospective cohort study in Toronto, Canada.

To investigate the adverse effects associated with a false positive 50 g glucose challenge test for gestational diabetes mellitus (GDM). Consecutive women attending a prenatal registration clinic at a large community hospital in suburban Toronto, Canada. Prospective cohort study of women between 12 and 24 weeks' gestation with no previous history of diabetes mellitus or GDM. Main outcome measures included anxiety (Spielberger's State-Trait Anxiety Inventory), depression (Centers for Epidemiologic Studies Depression Scale), perceived maternal health, and concern about health of the newborn. Among 2564 eligible subjects, there were 897 subjects with complete data at enrollment and at 32 weeks' gestation, including 88 who had false positive glucose challenge test results. At 32 weeks, only 20% (95% confidence limits 11%, 28%) of women with false positive glucose challenge test results rated their health as excellent, compared with 38% (35%, 42%) of those having negative results and those not tested (P = 0.001). These results were sustained at 36 weeks. There was no association between glucose challenge test result and the change in anxiety (P = 0.57), depression (P = 0.09) or concern about health of the newborn (P = 0.91) between baseline and 32 weeks' gestation, nor were these associations found at 36 weeks. False positive glucose challenge test results are about six times more likely than true positive results in the general population. Pregnant women with false positive GDM screening results experience a significant decline in their perception of their own health. These adverse effects should be taken into account when deciding about a policy of screening all pregnant women for gestational diabetes.