Cutoff value of 1 h, 50 g glucose challenge test for screening of gestational diabetes mellitus in a Japanese population

A total of 2651 consecutive native Japanese women who underwent a glucose challenge test (GCT) were retrospectively investigated. GCT was performed between 24 and 27 weeks of gestation; each subject received a 50 g oral glucose load without regard to the fasting or fed state, followed by a determination of 1 h venous plasma glucose level. Women demonstrating GCT exceeding 130 mg/dl received a 75 g, 2 h oral glucose tolerance test to determine whether or not they had gestational diabetes mellitus (GDM). All women with GDM were treated with a strict diabetic protocol including insulin therapy. Forty-nine (1.8%) women were diagnosed to have GDM. The receiver-operator characteristic curve identified a GCT finding above 140 mg/dl as the cutoff value for detecting GDM, which showed a sensitivity and specificity of 96 and 76%, respectively. Our results suggest that the cutoff value of a 50 g GCT is 140 mg/dl to identify pregnancies with GDM in a Japanese population.     

Gestational diabetes mellitus manifests in all trimesters of pregnancy

Screening for GDM is usually performed around 24-28 weeks of gestational age. We undertook a study to estimate the prevalence of glucose intolerance during different trimesters, as data in this aspect is sparse. A total of 4151 consecutive pregnant women irrespective of gestational weeks attending antenatal health posts across Chennai city underwent a 75 g OGTT recommended by WHO and diagnosed GDM if 2 hr PG value > or =140 mg/dl. Women who had normal OGTT at the first visit were screened with a repeat OGTT at the subsequent visits. Among the screened, 741 women (17.9%) had 2 hr PG> or =140 mg/dl and were identified to have gestational diabetes. Analysis based on gestational weeks revealed that out of the 741 GDM women, 121 (16.3%) were within 16 weeks, 166 (22.4%) were between 17 and 23 weeks and 454 (61.3%) were more than 24 weeks of gestation. Observation in this study was that 38.7% developed gestational diabetes even prior to 24th week of gestation. Out of the total 741 GDM women, 214 (28.9%) were diagnosed on repeat testing at subsequent visits. Glucose intolerance occurs in the early weeks of gestation. Women who had normal glucose tolerance in the first visit require repeat OGTT in the subsequent visits.     

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.     

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.     

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.     

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 in Iran: incidence, risk factors and pregnancy outcomes

The objective of this study was to determine the incidence of gestational diabetes mellitus (GDM) and compare fetal, maternal and neonatal complications amongst women with GDM and pregnant women with normal glucose tolerance in an urban Iranian population. In a prospective cohort study, universal screening for gestational diabetes mellitus was performed for 1310 pregnant women who were referred from private clinics and community health care centers to Fatemiyeh Hospital in Shahrood City. Screening was performed with a 50 g oral Glucose Challenge Test (GCT) with 130 mg/dl cut-off point, then a diagnostic 100 g Oral Glucose Tolerance Test (OGTT) was done according to Carpenter and Coustan criteria. The incidence of GDM was 4.8%. There were differences in risk factors: age >30 years, family history of diabetes, obesity, previous macrosomia, glycosuria between the two groups (P<0.001). Women with GDM had a higher rate of stillbirth (P<0.001; odds ratio 17.1, 95% CI=4.5-65.5), hydramnios (P<0.001; odds ratio 15.5, 95% CI=4.8-50.5), gestational hypertension (P<0.001; odds ratio 6, 95% CI=2.3-15.3), macrosomia (P<0.05; odds ratio 3.2, 95% CI=1.2-8.6) and caesarean section (P<0.001). We have found that the incidence of GDM in an urban Iranian population is similar to developed countries. Complications were more common in the GDM group than in the normal group and outcomes for women with persistent diabetes post-partum were particularly poor. We recommend screening for GDM in Iran, but further evaluation of selective screening and cost effectiveness will need to be performed. Measures to improve the outcome of GDM pregnancy will also need to be addressed in the future.     

Gestational diabetes mellitus in Korea: prevalence and prediction of glucose intolerance at early postpartum

To determine the prevalence of glucose intolerance in Korean women with gestational diabetes mellitus (GDM) between 6 and 8 weeks postpartum and identify which antepartum variables were predictive of postpartum diabetes and impaired glucose tolerance (IGT), we prospectively performed 75 g oral glucose tolerance test (OGTT) between 6 and 8 weeks postpartum in women with GDM. WHO criteria were used for classification of glucose tolerance postpartum. Of 392 women with GDM were detected during the study period, 311 women participated in this study. Of the 311 participants, 119 (38.3%) women were found to have persistent glucose intolerance; 47 (15.1%) had diabetes and 72 (23.2%) had IGT. The prevalence of postpartum IGT and diabetes increased in parallel with the metabolic severity during pregnancy. Multiple logistic regression analysis revealed that pre-pregnancy weight, gestational age at diagnosis of GDM, 2-h glucose and 3-h insulin concentrations of diagnostic OGTT were independently associated with postpartum diabetes. Pre-pregnancy weight, 2-h glucose and 1-h insulin concentrations were independently associated with postpartum IGT. Our results support the importance of postpartum testing in Korean women with GDM, and demonstrated that impaired beta-cell function and pre-pregnancy obesity were associated with glucose intolerance at early postpartum.     

妊娠期糖代谢异常对妊娠的不良影响

目的了解妊娠期糖代谢异常对孕妇和围生儿的影响。方法对10809名孕妇在孕24～28周做50g葡萄糖负荷试验，阳性者再做75gOGTT，据血糖结果分为糖代谢正常（GNGT）组、妊娠糖尿病（GDM）组和妊娠期糖耐量减低（GIGT）组，比较三组妊娠的结局。结果GDM和GIGT组的患病率分别为0．61％和2．50％。GDM组孕妇产后即时出血、剖宫产、妊娠高血压综合征、羊水过多、巨大儿、早产儿和新生儿低血糖的发生率均显著高于GNGT组；GIGT组剖宫产、羊水过多、巨大儿的发生率显著高于GNGT组，低体重儿发生率低于GNGT组。结论妊娠期糖代谢异常对孕产妇和围生儿有不良影响，因此应重视孕期糖代谢异常的筛查、诊断和治疗。     

Lack of predictive power of plasma lipids or lipoproteins for gestational diabetes mellitus in Japanese women

Aims/Introduction

To determine the diagnostic potential of plasma lipids and apolipoproteins in gestational diabetes mellitus (GDM), we carried out a retrospective cohort study of 1,161 Japanese women at 20–28 weeks of gestation who underwent a glucose challenge test (GCT).

Materials and Methods

A total of 1,161 Japanese women at 20–28 weeks of gestation underwent a GCT. Participants with a positive test (GCT[+]) underwent a subsequent oral glucose tolerance test. Clinical and biochemical parameters were determined and quantification of apolipoproteins (Apo), including ApoB, ApoB48, ApoA-I and ApoC-III, was carried out.

Results

The prevalence of GCT(+; with a 130 mg/dL glucose cut-off) and GDM was 20% and 4%, respectively. There was a trend for increased triglycerides and ApoC-III in GDM(+) participants. However, the difference in plasma triglycerides, ApoC-III or ApoB48 did not reach statistical significance between GDM(+) and GDM(−) women. Values of 1-h glucose (P < 0.001) and fasting glucose (P = 0.002) were significant risk factors for GDM.

Conclusions

Prediction of GDM using only the ApoC-III value is not easy, although triglycerides and ApoC-III were higher in the GDM(+) group. The present findings show no significant difference in plasma lipid levels between women diagnosed with GDM and those with normal glucose tolerance.     

Pre-gravid physical activity and reduced risk of glucose intolerance in pregnancy: the role of insulin sensitivity

Objective Pre‐gravid physical activity has been associated with a reduced risk of gestational diabetes mellitus (GDM), although neither the types of exercise nor the physiologic mechanisms underlying this protective effect have been well‐studied. Thus, we sought to study the relationships between types of pre‐gravid physical activity and metabolic parameters in pregnancy, including glucose tolerance, insulin sensitivity and β‐cell function. Design/patients/measurements A total of 851 women underwent a glucose challenge test (GCT) and a 3‐h oral glucose tolerance test (OGTT) in late pregnancy, yielding four glucose tolerance groups: (i) GDM; (ii) gestational impaired glucose tolerance (GIGT); (iii) abnormal GCT with normal glucose tolerance on OGTT (abnormal GCT NGT); and (iv) normal GCT with NGT on OGTT (normal GCT NGT). Pre‐gravid physical activity was assessed using the Baecke questionnaire, which measures (i) total physical activity and (ii) its three component domains: work, nonsport leisure‐time, and vigorous/sports activity. Results Glucose tolerance status improved across increasing quartiles of pre‐gravid total physical activity (P = 0·0244). Whereas neither work nor nonsport leisure‐time activity differed between glucose tolerance groups, pre‐gravid vigorous/sports activity was significantly higher in women with normal GCT NGT compared to women with (i) abnormal GCT NGT (P = 0·0018) (ii) GIGT (P = 0·0025), and (iii) GDM (P = 0·0044). In particular, vigorous/sports activity correlated with insulin sensitivity (measured by IS_OGTT) (r = 0·21, P < 0·0001). Furthermore, on multiple linear regression analysis, pre‐gravid vigorous/sports activity emerged as a significant independent predictor of IS_OGTT in pregnancy (t = 4·97, P < 0·0001). Conclusions Pre‐gravid vigorous/sports activity is associated with a reduced risk of glucose intolerance in pregnancy, an effect likely mediated by enhanced insulin sensitivity.     

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.     

Maternal ante-natal parameters as predictors of persistent postnatal glucose intolerance: a comparative study between Afro-Caribbeans, Asians and Caucasians.

AIMS: To measure the prevalence of persistent glucose intolerance at 6-12 weeks postpartum in various ethnic groups to assess the value of targeted postpartum screening. METHODS: A retrospective study was performed using computerized databases from two large maternity units within one UK region. Both units used the same screening strategy for gestational diabetes mellitus (GDM) and the same postpartum follow-up at 6-12 weeks using a 75-g oral glucose tolerance test (OGTT). A total of 221 women with a diagnosis of GDM/impaired glucose tolerance (IGT) in the index pregnancy in addition to a completed postpartum 75-g OGTT were studied. Of these, 91 were Caucasian, 89 were of Indo-Asian (Asian) origin and 41 were of Afro-Caribbean origin. RESULTS: The study showed that 35% Indo-Asians had persistent postpartum glucose intolerance compared with 7% Caucasians and 5% Afro-Caribbeans (P < 0.003). Insulin requirement during pregnancy and a diagnosis of gestational diabetes prior to 20 weeks of pregnancy were predictive for persistent postpartum glucose intolerance amongst Indo-Asians. CONCLUSIONS: The frequency of postpartum glucose intolerance among Indo-Asian women is significantly greater than among age-matched Caucasian and Afro-Caribbean women. We suggest that all Indo-Asian women with gestational diabetes should undergo postpartum screening for persistent glucose intolerance. However, in non-Asian women selective screening may be more cost effective.     

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).     

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.     

A single test procedure to diagnose gestational diabetes mellitus

Universal screening for gestational diabetes mellitus (GDM), detects more cases and improves maternal and offspring prognosis. Of all the screening tests, World Health Organization (WHO) procedure is simple and cost effective; the only disadvantage is that the pregnant woman has to come in the fasting state to undergo oral glucose tolerance test (OGTT). Hence, we undertook a study to elucidate a test that is casual and reliable to diagnose GDM. A total of 800 pregnant women underwent 75-g glucose challenge test (GCT) irrespective of the time of the last meal and their 2-h plasma glucose (PG) was estimated. They also underwent a 2-h 75-g OGTT recommended by WHO after 72 h. There was no statistically significant difference in the glycemic profile between GCT and WHO OGTT in the diagnosis of GDM. In conclusion, GCT performed irrespective of the last meal timing is a patient-friendly approach and causes least disturbance in the pregnant woman's routine activities.     

口服葡萄糖耐量试验不同取血次数对妊娠糖尿病诊断的影响

目的分析OGTT不同取血次数对妊娠糖尿病（GDM）诊断的影响。方法对1506例50g葡萄糖负荷试验（GCT）阳性的孕妇进行3hOGTT,观察各时间点组合的10种诊断方法的灵敏度、漏诊率、总符合率、阴性预测值等指标,并与标准诊断方法相比进行一致性检验。结果1-2-3h法诊断GDM的Kappa值为0．936（P〈0．01）。结论对50gGCT阳性的孕妇行OGTT时,FPG对GDM的诊断影响最小,如需减少取血次数,可考虑取消之。     

Risk factors associated with persistence of glucose intolerance one year after gestational diabetes

One hundred and fourteen women, 89 with previous gestational diabetes and 25 who showed a normal glucose tolerance during pregnancy were retested by OGTT one year postpartum. Gestational diabetics were divided into two groups according to the severity of glucose intolerance. 97.6% of mild gestational diabetics and 79.2% of severe cases returned to normality postpartum. A different behaviour of these groups was shown by comparing OGTT areas before and after delivery. Body Mass Index and the degree of severity of glucose intolerance were shown to be predictive for the persistence of the abnormality postpartum. Follow-up for three to four years was continued in 8 cases of previous severe gestational diabetes. In seven of them a glucose intolerance appeared again during the follow-up after the temporary improvement one year after delivery.     

Association between different levels of dysglycemia and metabolic syndrome in pregnancy

Background

In this study, we sought to evaluate the prevalence of metabolic syndrome (MS) in a cohort of pregnant women with a wide range of glucose tolerance, prepregnancy risk factors for MS during pregnancy, and the effects of MS in the outcomes in the mother and in the newborn.

Methods

One hundred and thirty six women with positive screening for gestational diabetes mellitus (GDM) were classified by two diagnostic methods: glycemic profile and 100 g OGTT as normoglycemic, mild gestational hyperglycemic, GDM, and overt GDM. Markers of MS were measured between 2428^th during the screening.

Results

The prevalence of MS was: 0%; 20.0%; 23.5% and 36.4% in normoglycemic, mild hyperglycemic, GDM, and overt GDM groups, respectively. Previous history of GDM with or without insulin use, BMI ≥ 25, hypertension, family history of diabetes in first degree relatives, non-Caucasian ethnicity, history of prematurity and polihydramnios were statistically significant prepregnancy predictors for MS in the index pregnancy, that by its turn increased the adverse outcomes in the mother and in the newborn.

Conclusion

The prevalence of MS increases with the worsening of glucose tolerance; impaired glycemic profile identifies pregnancies with important metabolic abnormalities even in the presence of a normal OGTT, in patients that are not classified as having GDM.     

A postnatal fasting plasma glucose is useful in determining which women with gestational diabetes should undergo a postnatal oral glucose tolerance test.

AIMS: It is recommended that women with gestational diabetes (GDM) should have a 6-week postnatal oral glucose tolerance test (OGTT). As this test may be unpleasant, time-consuming and has resource implications, we evaluated whether the 6-week postnatal fasting glucose could be used to determine which women should undergo an OGTT. METHODS: All women with GDM, diagnosed according to the World Health Organization criteria, who were delivered at the Princess Anne Hospital, Southampton between May 2000 and May 2002, were recommended to have an OGTT. The results of the fasting plasma glucose concentration were assessed in relation to the 2-h glucose value. RESULTS: One-hundred and fifty-two women with GDM were delivered. Thirty (19.7%) women refused an OGTT or failed to attend. In the 122 OGTTs, three (2.4%; 95% confidence interval 0.8, 7) women had diabetes, three had impaired glucose tolerance and four had impaired fasting glycaemia. No woman with a normal test had fasting glucose of > or =6.0 mmol/l. Fasting glucose was correlated with the 2-h glucose (r=0.62, P<0.0001). Only 10 (8.1%) of the OGTTs would have been performed if only women with fasting glucose of > or =6.0 mmol/l underwent the test. The sensitivity and specificity of this approach for the diagnosis of postnatal diabetes is 100% and 94%, respectively. Linear regression methods indicate that it would miss fewer than three in 10 000 cases. CONCLUSIONS: In our population, a 6-week postnatal fasting plasma glucose is useful in determining which women with gestational diabetes should undergo an OGTT. Consequently we now perform OGTT only in women whose postnatal fasting plasma glucose is > or =6.0 mmol/l.