Gestational diabetes mellitus

Diagnostic controversy: gestational diabetes and the meaning of risk for pima Indian women

Gestational diabetes is the one form of this well known, chronic disease of development that disappears. After the birth of the child, the mother's glucose levels typically return to normal. As a harbinger of things to come, gestational diabetes conveys greater risk for later type 2 (previously "non-insulin dependent") diabetes in both the mother and child. Thus, pregnant women have become a central target for prevention of this disease in the entire Pima population. Based on ethnographic interviews conducted between 1999 and 2000, I discuss the negotiated meanings of risk, "borderline" diabetes, and women's personal knowledge and experiences of diabetes, particularly during the highly surveilled period of pregnancy. I also highlight the heterogeneity of professional discourse pertaining to gestational diabetes, most notably the debate surrounding its diagnosis. Significantly, women's narratives reveal the same set of questions as is raised in the professional debate. Implications for diabetes prevention and for balancing the increased surveillance of pregnant women with clinical strategies that privilege their experience and perspectives are also discussed.

Impaired maternal glucose homeostasis during pregnancy is associated with low status of long-chain polyunsaturated fatty acids (LCP) and essential fatty acids (EFA) in the fetus

Low status of long-chain polyunsaturated fatty acids (LCP) and essential fatty acids (EFA) in the fetus is associated with less favorable neonatal neurological condition. A 'relative', rather than 'absolute' EFA deficiency might explain this finding. A relative EFA deficiency may derive from impaired maternal glucose homeostasis. We measured fatty acids in umbilical vessels of infants born to 7 mothers with (gestational) diabetes mellitus and of 258 infants born to healthy mothers. Umbilical veins of infants of diabetic mothers had higher omega7 and omega9 fatty acids and DHA deficiency index and lower 20:4omega6 and EFA index. Their umbilical arteries had higher omega7 and omega9 fatty acids, and lower 20:4omega6, LCP and EFA index. We conclude that children born to mothers with poor glucose homeostasis have lower EFA and LCP status, which is consistent with a 'relative deficiency' deriving from augmented de novo fatty acid synthesis from the abundant glucose.

Does maternal hypoglycemia during screening glucose assessment identify a pregnancy at-risk for adverse perinatal outcome?

OBJECTIVE

To determine the perinatal outcome in pregnancies with maternal hypoglycemia following a second trimester oral glucose challenge test (GCT).

STUDY DESIGN

Retrospective case-control study of pregnancies undergoing a second trimester 1-hour oral glucose challenge test (GCT). Hypoglycemic pregnancies (<88 mg/dl) were matched with pregnancies with 1-hour glucoses of >88 mg/dl. Antepartum, intrapartum, and neonatal outcomes were assessed.

RESULTS

Over 29 months, 334 hypoglycemic singleton pregnancies were matched with 334 controls. A greater number of special/neonatal intensive care unit (SCN/NICU) admissions occurred in the hypoglycemic group (48/334 (14.4%) vs 29/334 (8.7%) in the control group) (p=0.02). The SCN/NICU admission rate remained after controlling for maternal hypertension, smoking, and preterm birth (p=0.037). The development of pregnancy-induced hypertension in women with hypoglycemia 24/334 (7.2%) compared with euglycemic women 13/334 (3.9%, p<0.06) was not significant.

CONCLUSION

Admission to SCN/NICU is increased in pregnant women with hypoglycemia following a GCT.

Alternative site self blood glucose testing is preferred by women with gestational diabetes

BACKGROUND

Women with gestational diabetes (GDM) need to assimilate information and management skills rapidly for their diabetes to prevent adverse pregnancy outcomes. Strict glycaemic control is necessary and is improved by regular self-monitoring of blood glucose. The Softsense meter (MediSense Products, Witney, UK) is used on less sensitive body sites and combines lancing with testing. The study aim was to compare alternative site testing with traditional blood glucose monitoring in pregnancy.

SUBJECTS AND METHODS

An open-label randomised crossover study using Softsense and Optium (MediSense Products) meters was performed in 33 women with GDM and 19 women with pre-existing diabetes. Each meter was used for 2 weeks. Ease of use and learning, pain, convenience, and effect on daily activities were assessed by a visual analogue questionnaire.

RESULTS

Women with GDM found the Softsense less painful (P = 0.0001) and easier to use (P = 0.03). At the end of the study, 25 chose the Softsense meter in preference to the Optium meter for further testing (P = 0.0001). In contrast, women with pre-existing diabetes found the Optium significantly less messy, less disruptive, and easier to use outside the home.

CONCLUSIONS

Women with GDM preferred the Softsense meter because of its ease of use and painlessness. Women with pre-existing diabetes found this meter less convenient, primarily because of its bulkiness.

Optimal timing for postprandial glucose measurement in pregnant women with diabetes and a non-diabetic pregnant population evaluated by the Continuous Glucose Monitoring System (CGMS)

OBJECTIVE

Using the Continuous Glucose Monitoring System (CGMS; Medtronic Minimed) for a group of pregnant women with and without glucose intolerance, we attempted to answer the following questions: (1) when does the physiological peak of postprandial glucose occur?; (2) do non-diabetic pregnant women and pregnant women with diabetes have different postprandial glucose profiles?; and (3) what is the optimal time for postprandial glucose measurement rated according to clinical outcome?

METHODS

We included 53 pregnant women in our study. Based on the criteria of the German Diabetes Association (fasting, 5.0 mmol/L; 1-h, 10.0 mmol/L; 2-h, 8.6 mmol/L) we included 13 women with gestational diabetes, four with type 1 diabetes and 36 non-diabetic pregnant (NDP) women. Gestational and type 1 diabetics were classed as one group: pregnancy complicated by diabetes (PCD). Patients with carbohydrate intolerance underwent dietary counseling in accordance with the recommendations of the American Diabetes Association. Patients received a CGMS for use over 72 h. This was calibrated seven times a day with an Accu-Check. The pre- and postprandial glucose levels were documented at 15-min intervals for 3 h from the beginning of each meal. The postprandial data from the three meals were added. The group was divided according to three clinical outcome parameters: mode of delivery, birth weight percentile, and diabetes-associated complications.

RESULTS

Statistically significant differences between groups were found for body mass index, fetal birth weight and oral glucose tolerance test. No significant differences were found for age, parity and gestational age, mode of delivery, and diabetes-associated complications. The sensor provided similar numbers of measurements in both groups (278+/-43 vs. 298+/-73, P = 0.507). The postprandial glucose peak was reached after 82+/-18 min in the non-diabetics vs. 74+/-23 min in the PCD group (not significant). Postprandial glucose values were normally slightly higher in PCD (not significant). We added the postprandial glucose values at each time interval for the three meals for each day. For the sum, there was a significant difference between the measurements at 120 min and at 135 min postprandial (P < 0.05). Dividing the group by clinical outcome showed a significant difference between the postprandial time intervals of 75 min and 105 min (P < 0.05). In addition, the time interval was different from 60 min to 135 min for the mode of delivery and birth weight percentile (P < 0.05).

CONCLUSION

The 120-min interval is too long and has a lower correlation to clinical outcome parameters than earlier measurements. Our findings show that the optimal time for testing is between 45 and 120 min postprandial. Based on our practical experience and dietary recommendations, we would prefer a 60-min interval, because patients can calculate this more easily and can have more freedom to eat the recommended number of snacks.

Potential impact of American Diabetes Association (2000) criteria for diagnosis of gestational diabetes mellitus in Spain

AIMS/HYPOTHESIS

This study was carried out to determine the impact of American Diabetes Association (ADA) 2000 criteria for the diagnosis of gestational diabetes mellitus (GDM) in the Spanish population.

METHODS

Pregnant women were assigned to one of four categories: negative screenees, false-positive screenees, ADA-only-GDM (untreated) and GDM according to National Diabetes Data Group (NDDG) criteria (treated). Fetal macrosomia and Caesarean section were defined as primary outcomes, with seven additional secondary outcomes.

RESULTS

Of 9,270 pregnant women screened for GDM, 819 (8.8%) met NDDG criteria. If the threshold for defining GDM had been lowered to ADA criteria, an additional 2.8% of women would have been defined as having the condition (relative increase of 31.8%). Maternal characteristics of women with ADA-only-GDM were between those of false-positive screenees and women with NDDG-GDM. The risk of diabetes-associated complications was slightly elevated in the individuals who would have been classified as abnormal only after the adoption of ADA criteria. In addition, the ADA-only-GDM contribution to morbidity was lower than that of other variables, especially BMI.

CONCLUSIONS/INTERPRETATION

Use of the ADA criteria to identify GDM would result in a 31.8% increase in prevalence compared with NDDG criteria. However, as the contribution of these additionally diagnosed cases to adverse GDM outcomes is not substantial, a change in diagnostic criteria is not warranted in our setting.

Gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is defined as glucose intolerance of various degrees that is first detected during pregnancy. GDM is detected through the screening of pregnant women for clinical risk factors and, among at-risk women, testing for abnormal glucose tolerance that is usually, but not invariably, mild and asymptomatic. GDM appears to result from the same broad spectrum of physiological and genetic abnormalities that characterize diabetes outside of pregnancy. Indeed, women with GDM are at high risk for having or developing diabetes when they are not pregnant. Thus, GDM provides a unique opportunity to study the early pathogenesis of diabetes and to develop interventions to prevent the disease.

Features and outcome of pregnancies complicated by impaired glucose tolerance and gestational diabetes diagnosed using different criteria in a Spanish population

The main objective of this study was to determine the prevalence and risk of complications of a population of Spanish pregnant women with GDM diagnosed following the O'Sullivan-Mahan "standard" criteria, compared with pregnant women with GDM diagnosed using the "new" Carpenter-Coustan criteria. In Spain, limited data are published concerning as the prevalence of GDM and its morbidity. In this sense, the "new" criteria for GDM diagnosis has not been adopted in Spain due to the absence of adequate studies. We retrospectively reviewed all pregnancies handled at our center from 1999 to 2001 (n=6248). Using the standard and the new criteria, the prevalence of GDM was 6.46 and 6.75%, respectively. GDM patients diagnosed using the new criteria showed the same pregnancy evolution that patients diagnosed with the classic criteria. Those patients complicated only with impaired glucose intolerance (IGT) (0.94%) showed a worst outcome. Based on the pregnancy evolution observed, it is not recommended that the new GDM diagnostic criteria be adopted in Spain. More accurate follow-up of patients with IGT is needed.

Adiponectin and beta cell dysfunction in gestational diabetes: pathophysiological implications

AIMS/HYPOTHESIS

Gestational diabetes mellitus (GDM) identifies a population of young women at high risk of developing type 2 diabetes and thus provides an excellent model for studying early events in the natural history of this disease. Adiponectin, a novel adipocyte-derived protein with insulin-sensitising properties, has been proposed as a factor linking insulin resistance and beta cell dysfunction in the pathogenesis of type 2 diabetes. We conducted the current investigation to determine whether adiponectin is associated with beta cell dysfunction in GDM.

METHODS

We studied 180 women undergoing OGTT in late pregnancy. Based on the OGTT results, participants were stratified into three groups: (1) NGT (n=93); (2) IGT (n=39); and (3) GDM (n=48). First-phase insulin secretion was determined using a validated index previously proposed by Stumvoll. Insulin sensitivity was assessed using the validated OGTT insulin sensitivity index of Matsuda and DeFronzo (IS(OGTT)).

RESULTS

To evaluate beta cell function in relation to ambient insulin sensitivity, an insulin secretion-sensitivity index (ISSI) was derived from the product of the Stumvoll index and the IS(OGTT), based on the existence of the predicted hyperbolic relationship between these two measures. Mean ISSI was highest in the NGT group (6,731), followed by that in the IGT group (4,976) and then that in the GDM group (3,300) (overall p<0.0001), compatible with the notion of declining beta cell function across these glucose tolerance groups. Importantly, adiponectin was significantly correlated with ISSI (r=0.34, p<0.0001), with a stepwise increase in mean ISSI observed per tertile of adiponectin concentration (trend p<0.0001). In multivariate linear regression analysis, ISSI was positively correlated with adiponectin and negatively correlated with GDM, IGT and C-reactive protein (r(2)=0.54).

CONCLUSIONS/INTERPRETATION

Adiponectin concentration is an independent correlate of beta cell function in late pregnancy. As such, adiponectin may play a key role in mediating insulin resistance and beta cell dysfunction in the pathogenesis of diabetes.

Report from the CDC. The National Public Health Initiative on Diabetes and Women's Health: leading the way for women with and at risk for diabetes

Diabetes is a serious public health problem in the United States. The burden of the disease has had a significant impact on individuals, communities, and society at large, and the number of people with diabetes is expected to double by the year 2025. In response to the growing burden of the disease and the profound health consequences for women and their offspring, the National Public Health Initiative on Diabetes and Women's Health convened a call-to-action conference to form a collective effort to address diabetes and women's health issues. This paper documents the process of developing a call-to-action conference and identifying potential stakeholders and presents results from the conference and the accomplishments of the National Public Health Initiative on Diabetes and Women's Health.

Increasing prevalence of gestational diabetes mellitus (GDM) over time and by birth cohort: Kaiser Permanente of Colorado GDM Screening Program

OBJECTIVE

The prevalence of gestational diabetes mellitus (GDM) varies in direct proportion with the prevalence of type 2 diabetes in a given population or ethnic group. Given that the number of people with diabetes worldwide is expected to increase at record levels through 2030, we examined temporal trends in GDM among diverse ethnic groups.

RESEARCH DESIGN AND METHODS

Kaiser Permanente of Colorado (KPCO) has used a standard protocol to universally screen for GDM since 1994. This report is based on 36,403 KPCO singleton pregnancies occurring between 1994 and 2002 and examines trends in GDM prevalence among women with diverse ethnic backgrounds.

RESULTS

The prevalence of GDM among KPCO members doubled from 1994 to 2002 (2.1-4.1%, P < 0.001), with significant increases in all racial/ethnic groups. In logistic regression, year of diagnosis (odds ratio [OR] and 95% CI per 1 year = 1.12 [1.09-1.14]), mother's age (OR per 5 years = 1.7 [1.6-1.8]) and ethnicity other than non-Hispanic white (OR = 2.1 [1.9-2.4]) were all significantly associated with GDM. Birth year remained significant (OR = 1.06, P = 0.006), even after adjusting for prior GDM history.

CONCLUSIONS

This study shows that the prevalence of GDM is increasing in a universally screened multiethnic population. The increasing GDM prevalence suggests that the vicious cycle of diabetes in pregnancy initially described among Pima Indians may also be occurring among other U.S. ethnic groups.

Gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is defined as glucose intolerance of various degrees that is first detected during pregnancy. GDM is detected through the screening of pregnant women for clinical risk factors and, among at-risk women, testing for abnormal glucose tolerance that is usually, but not invariably, mild and asymptomatic. GDM appears to result from the same broad spectrum of physiological and genetic abnormalities that characterize diabetes outside of pregnancy. Indeed, women with GDM are at high risk for having or developing diabetes when they are not pregnant. Thus, GDM provides a unique opportunity to study the early pathogenesis of diabetes and to develop interventions to prevent the disease.

A population-based screening for gestational diabetes mellitus in non-diabetic women in Bahrain

BACKGROUND

Maternal hyperglycemia is considered a risk factor for fetal morbidity. Since there is a high prevalence of diabetes mellitus among the population of Bahrain, we conducted a prospective population-based study of gestational diabetes mellitus (GDM) in non-diabetic pregnant women.

SUBJECTS AND METHODS

All non-diabetic pregnant women attending antenatal clinics during January 2001 to December 2002 (n=10,495) were screened for GDM during the 24th to 28th weeks of gestation. All positive subjects based on a 50-g glucose challenge test (GCT) were further evaluated by a diagnostic 75-g oral glucose tolerance test (OGTT). The birth weight of the child and post-delivery insulin resistance were monitored. The homeostasis model of insulin resistance (HOMA-IR) was used to assess insulin resistance.

RESULTS

Of 10,495 non-diabetic pregnant women screened, 32.8% (n=3443) had plasma glucose > or = 7.8 mmol/L (140 mg/dL) in the GCT. The 75-g OGTT found a prevalence of GDM of 13.5%. There were twice as many Bahrainis as expatriates. Of children born to women with GDM, 6.5% had a birth weight > 4000 g. Post-delivery evaluation of insulin resistance indicated that 33% of women with GDM had a HOMA-IR value > 2.

CONCLUSION

The population of Bahrain is a high-risk ethnic group for GDM. The association of insulin resistance in the post-gravid state with GDM among 33% of the study population suggests that insulin resistance, the possible cause of the pathophysiological mechanism underlying the development of gestational diabetes, continues in the post gravid state.

Recent advances in the treatment of gestational diabetes

Despite four decades of research there is a lack of international consensus on the screening, diagnosis, treatment and follow up of gestational diabetes mellitus (GDM). Currently, GDM is managed by diet modification, exercise and exogenous human insulin. During the last decade, several insulin analogues and oral antihyperglycaemic drugs have revolutionised the management of diabetes mellitus in non-pregnant women. Most of these recent drugs still remain investigational in GDM due to concerns about their safety in pregnancy. This review will focus primarily on the pharmacological treatment of GDM. It will objectively assess the value of these exciting new drugs in pregnancy as they could potentially benefit every woman with GDM.

Incidence, natural history, and risk factors for biliary sludge and stones during pregnancy

Gallstones are strongly associated with higher parity in women. This study prospectively assessed the incidence, natural history, and risk factors for biliary sludge and stones during pregnancy and the postpartum in 3,254 women at an army medical center. Women with a prior cholecystectomy or with stones at their first study ultrasound were excluded. Gallbladder ultrasound and subject questionnaires were obtained in each trimester and at 4 to 6 weeks postpartum. Serum glucose, lipids, insulin, leptin, estradiol, and progesterone were measured at 26 to 28 weeks' gestation. A nested case-control study was done to examine the effects of serum leptin and insulin on incident gallbladder disease. At least two study ultrasounds were available for 3,254 women. Sludge or stones had been found on at least one study ultrasound in 5.1% by the second trimester, 7.9% by the third trimester, and 10.2% by 4 to 6 weeks postpartum. Regression of sludge and stones was common, such that overall 4.2% had new sludge or stones on the postpartum ultrasound. Twenty-eight women (0.8%) underwent cholecystectomy within the first year postpartum. Prepregnancy body mass index was a strong predictor of incident gallbladder disease (P < .001). Serum leptin was independently associated with gallbladder disease (odds ratio per 1 ng/dL increase, 1.05; 95% CI, 1.01, 1.11), even after adjusting for body mass index. In conclusion, incident gallbladder sludge and stones are common in pregnancy and the postpartum, and cholecystectomy is frequently done within the first year postpartum. Prepregnancy obesity and serum leptin are strong risk factors for pregnancy-associated gallbladder disease.

Maternal plasma ascorbic Acid (vitamin C) and risk of gestational diabetes mellitus

BACKGROUND

Antioxidants, particularly vitamin C (ascorbic acid), have the capacity to influence glucose tolerance. Modification of diet could reduce the likelihood of developing gestational diabetes mellitus.

METHODS

In a prospective cohort study of pregnant women, we studied the association of maternal plasma ascorbic acid concentrations, measured at an average of 13 weeks' gestation, with subsequent risk of gestational diabetes. Maternal plasma ascorbic acid concentrations were determined using automated enzymatic procedures. Dietary vitamin C intake during the periconceptional period and early pregnancy was ascertained using a semiquantitative food frequency questionnaire. We fitted generalized linear models to derive estimates of relative risks and 95% confidence intervals (CIs).

RESULTS

Approximately 4% (n = 33) of 755 women who completed pregnancy developed gestational diabetes mellitus. Plasma ascorbic acid concentrations were inversely associated with the risk of gestational diabetes (P for trend = 0.023). After adjusting for maternal age, race, prepregnancy adiposity, parity, family history of type 2 diabetes, and household income, women with plasma ascorbic acid <55.9 micromol/L (lowest quartile) experienced a 3.1-fold increased risk of gestational diabetes (95% CI = 1.0 - 9.7) compared with women whose concentrations were > or = 74.6 micromol/L (upper quartile). Women who consumed <70 mg vitamin C daily experienced a 1.8-fold increased risk of gestational diabetes compared with women who consumed higher amounts (95% CI = 0.8 - 4.4).

CONCLUSIONS

If confirmed, our results raise the possibility that current efforts to encourage populations to consume diets rich in antioxidants, including vitamin C, could reduce the occurrence of gestational diabetes mellitus.

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.

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.

A 2 hour versus the 3 hour 100 g glucose tolerance test for diagnosing gestational diabetes mellitus

AIM

To determine how the omission of the third hour glucose measurement of the 100 g oral glucose tolerance test (GTT) affects the diagnosis of gestational diabetes mellitus (GDM).

METHODS

Retrospective chart review of 876 women delivered in a tertiary care hospital in Israel during a three-year period, who underwent a 100 g 3 hour oral GTT following an abnormal 50 g glucose screen. GDM was diagnosed according to the "criterion standard" accepted in the Fourth International Workshop Conference on GDM. The results of the 100 g 3 hour oral GTT were then retrospectively re-evaluated by omission of the third hour plasma glucose measurement from the "criterion standard".

RESULTS

GDM was diagnosed in 28.4% of the study. patients, while the omission of the third hour glucose measurement resulted in a 26.4% diagnosis of GDM. The perinatal data of the 18-omitted cases suggests that their exclusion from the GDM group would not have altered substantially the perinatal outcome of the study cohort.

CONCLUSIONS

A 100 g 2 hour oral GTT is a simple and economic alternative to the 100 g 3 hour oral GTT.

Targeting insulin resistance and beta-cell dysfunction: the role of thiazolidinediones

Insulin resistance and beta-cell dysfunction are fundamental defects that contribute to the development of type 2 diabetes, and as such are targets for primary prevention of disease progression. The two parameters are linked by several factors, including glucotoxicity and lipotoxicity, and recent research has enlightened understanding of the molecular mechanisms underlying the development and progression of the disease. Historically, type 2 diabetes has been managed by controlling hyperglycemia, using agents that increase insulin levels or reduce hepatic glucose production, as exemplified by the United Kingdom Prospective Diabetes Study. The thiazolidinediones control hyperglycemia by targeting the fundamental defects of the disease, and have shown well-documented improvements in insulin sensitivity and beta-cell function, both in monotherapy and in combination with other oral antidiabetic agents. TRoglitazone In the Prevention Of Diabetes (TRIPOD) has demonstrated the potential for thiazolidinediones to delay progression to type 2 diabetes. Prospective studies such as Diabetes REduction Approaches with ramipril and rosiglitazone Medications (DREAM) are currently evaluating the long-term effects of thiazolidinediones on metabolic status and disease progression.

Spectrum of hypertensive emergencies in pregnancy

Hypertension in pregnancy represents a spectrum of clinical entities, including pregnancy-induced hypertension (PIH), preeclampsia, eclampsia, and hemolysis, elevated liver enzyme levels, low platelet count syndrome. Although hypertension is a common denominator in this group of disorders, the pathogenesis, clinical features, and clinical course of these disorders is variable and somewhat distinct. Therapy must be tailored to the clinical entity and the patient. The incidence and prevalence of preeclampsia and eclampsia is decreasing worldwide. This decrease partly may be caused by the improved treatment of PIH and improved obstetrical services.

To die or not to die: the function of the transcription factor NF-kappaB in embryos exposed to stress

BACKGROUND

Cytokines operating in the embryo and embryonic microenvironment determine, to a significant extent, whether pregnancy is completed successfully or results in embryonic loss or maldevelopment. They act as activators of specific transcription factors, which control cell responses such as cell proliferation differentiation and apoptosis. One such transcription factor is the nuclear factor-kappaB (NF-kappaB), which is presently seen as a key molecule controlling the apoptosis process. In the light of evidence that a majority of embryopathic stresses, regardless of their nature, first disturb the apoptotic process, it is conceivable, that NF-kappaB may play an important role in regulating the resistance of embryos to embryopathic stresses. In this brief review, we discuss such a possibility based on data characterizing expression and function of NF-kappaB in the embryo and extraembryonic tissues during normal embryogenesis as well as after exposure to various embryopathic stresses.

METHODS

Critical review of existing data.

RESULTS

Data summarized in this review suggest that (a) practically all NF-kappaB/Rel family members are expressed in embryonic, trophoblast and uterine cells in a developmental stage- and cell type-specific manner; (b) NF-kappaB-mediated anti-apoptotic signaling in embryonic cells seems to be indispensable for proper development during the organogenesis stage, (c) NF-kappaB activity in stress-targeted embryonic and extraembryonic structures directly correlates with their ability to resist stress-induced process of embryo loss and maldevelopment.

CONCLUSION

Data presented in this review suggest that NF-kappaB may act as a protector of embryos exposed to embryopathic stresses, possibly, because of the ability of NF-kappaB to prevent the induction of programmed cell death as well as to activate cell proliferation.

Should we continue or stop insulin sensitizing drugs during pregnancy?

PURPOSE OF REVIEW

The use of insulin sensitizing drugs such as metformin in polycystic ovary syndrome has been increasingly popular and validated by systematic reviews. There has also been an interest in the use of metformin for gestational diabetes. However, administration of metformin to prevent miscarriage is controversial and widespread use of this drug in early pregnancy requires investigation.

RECENT FINDINGS

There are claims that miscarriage and gestational diabetes are more common in polycystic ovary syndrome and that use of insulin sensitizers improves outcomes dramatically. This review suggests there is no evidence for increased risk of miscarriage solely due to polycystic ovary syndrome and that there are insufficient data for promoting therapy with metformin. There is some reason for use of metformin in mid-pregnancy for gestational diabetes but better evidence from randomized controlled trials is urgently needed.

SUMMARY

The use of metformin in early pregnancy for reducing the risk of miscarriage should be avoided outside of the context of properly designed prospective randomized trials. Safety in early pregnancy appears to be reassuring but not completely proven. The use of metformin in mid-pregnancy for gestational diabetes appears more logical but also needs adequate trials before general use is advocated.

A prospective study of maternal serum C-reactive protein (CRP) concentrations and risk of gestational diabetes mellitus

Low-grade systemic inflammation is associated with an increased risk of type 2 diabetes mellitus. Limited available data suggest inflammatory factors are predictive of gestational diabetes (GDM), a condition that is biochemically similar to type 2 diabetes. We examined the association between C-reactive protein (CRP) and GDM risk. Women were recruited before 16 weeks gestation and were followed until delivery. Maternal serum CRP (collected at 13 weeks' gestation, on average) was measured by a competitive immunoassay. We used generalised linear models to derive estimates of relative risks and 95% confidence intervals [CI]. Approximately 4.5% of the cohort (38 of 851) developed GDM. Elevated CRP was positively associated with GDM risk (P for trend = 0.007). After adjusting for maternal prepregnancy body mass index (BMI), family history of type 2 diabetes and nulliparity, women with CRP in the highest tertile experienced a 3.5-fold increased risk of GDM [95% CI 1.2, 9.8] as compared with those in the lowest tertile. The association between CRP and GDM was evident when analyses were restricted to lean women (BMI < 25 kg/m(2)). Lean women with CRP > or = 5.3 mg/L experienced a 3.7-fold increased risk of GDM [95% CI 1.6, 8.7] as compared with women with CRP < 5.3 mg/L. Systemic inflammation is associated with an increased risk of GDM, and the association is independent of maternal prepregnancy adiposity.

Haptoglobin phenotype and gestational diabetes

OBJECTIVE

Haptoglobin (Hp), an Hb-binding plasma protein, exists in two major allelic variants. Hp1 has higher Hb binding and antioxidant capacity compared with Hp2. Individuals with Hp1 exhibit a lower incidence of angiopathies. Gestational diabetes mellitus (GDM) is an early manifestation of type 2 diabetes in pregnant women. It is usually confined to the time of gestation, but carries an increased risk to develop type 2 diabetes later in life.

RESEARCH DESIGN AND METHODS

From consecutive Caucasian pregnant women (n = 250) referred for oral glucose tolerance testing, the Hp phenotype was determined. Significance of distribution and odds ratios (ORs) associated with Hp phenotype were calculated for women with GDM (n = 110) and women with normal glucose tolerance (n = 140).

RESULTS

-Frequency of GDM in Hp phenotype classes increased with the number of Hp2 alleles (P < 0.001). ORs for GDM in women heterozygous and homozygous for Hp2 were 2.7 (95% CI 1.06-6.84) and 4.2 (1.67-10.55), respectively.

CONCLUSIONS

Hp phenotype is an apparent risk factor for the development of GDM in our study population. This might be due to the low antioxidative potential of Hp2 compared with Hp1.

Pregnancy: a stress test for life

PURPOSE OF REVIEW

This review describes how the physiological demands of pregnancy act as a maternal stress test that can predict a woman's health in later life. Pregnancy transiently catapults a woman into a metabolic syndrome that predisposes to vascular endothelial dysfunction. Women who are already predisposed to this phenotype develop gestational hypertension or diabetes mellitus, which re-emerge in later life as the metabolic syndrome returns. Pregnancy can also temporarily unmask sub-clinical disease, which may return in later life when the effects of ageing diminish the limited reserves of a vulnerable organ.

RECENT FINDINGS

Recent studies have attempted to assess how gestational syndromes affect the risk for a woman of developing a diverse range of diseases in later life. As well as cardiovascular disease and diabetes mellitus, pregnancy can reveal a vulnerability to thyroid and pituitary disorders, liver and renal disease, depression, thrombosis and even cancer.

SUMMARY

Although our knowledge of this phenomenon is incomplete, women who have had gestational syndromes, in particular pregnancy-induced hypertension/preeclampsia or gestational diabetes, should make lifestyle changes that will reduce their risk of cardiovascular disease in later life.

Plasma adiponectin, insulin sensitivity, and subclinical inflammation in women with prior gestational diabetes mellitus

OBJECTIVE

Women with prior gestational diabetes mellitus (pGDM) are at increased risk of developing type 2 diabetes and associated vasculopathy. Because increased fat mass and inflammatory processes are angiopathic risk factors, the relationship between insulin sensitivity, parameters of subclinical inflammation, and plasma concentrations of adipocytokines was investigated in pGDM both at 3 months and 12 months after delivery.

RESEARCH DESIGN AND METHODS

Insulin sensitivity (through a frequently sampled intravenous glucose tolerance test) and plasma concentrations of ultrasensitive C-reactive protein (CRP), adiponectin, plasminogen activator inhibitor (PAI)-1, tumor necrosis factor-alpha, leptin, and interleukin-6 were measured in 89 pGDM (BMI 26.9 +/- 0.5 kg/m(2), age 32 +/- 0.5 years) and in 19 women with normal glucose tolerance during pregnancy (NGT) (23.7 +/- 0.9 kg/m(2), 31 +/- 1.3 years).

RESULTS

pGDM showed lower (P < 0.0001) plasma adiponectin (6.7 +/- 0.2 microg/ml) than NGT (9.8 +/- 0.6 microg/ml) and a decreased (P < 0.003) insulin sensitivity index (S(i)) and disposition index (P < 0.03), but increased plasma leptin (P < 0.003), PAI-1 (P < 0.002), and CRP (P < 0.03). After adjustment for body fat mass, plasma adiponectin remained lower in pGDM (P < 0.004) and correlated positively with S(i) (P < 0.003) and HDL cholesterol (P < 0.0001) but negatively with plasma glucose (2-h oral glucose tolerance test [OGTT]) (P < 0.0001), leptin (P < 0.01), CRP (P < 0.007), and PAI-1 (P < 0.0001). On regression analysis, only HDL cholesterol, postload (2-h OGTT) plasma glucose, and S(i) remained significant predictors of plasma adiponectin, explaining 42% of its variability. Of note, adiponectin further decreased (P < 0.05) only in insulin-resistant pGDM despite unchanged body fat content and distribution after a 1-year follow-up.

CONCLUSIONS

Lower plasma adiponectin concentrations characterize women with previous GDM independently of the prevailing insulin sensitivity or the degree of obesity and are associated with subclinical inflammation and atherogenic parameters.

Oral Hypoglycemic Agents in Pregnancy

Pregnancies in diabetic women are associated with increased risk of spontaneous abortion, congenital malformations, preeclampsia, preterm labor, macrosomia, shoulder dystocia, and cesarean section. Advances in antepartum cares and strict adherence to dietary and insulin regimens have been shown to significantly reduce the rate of maternal morbidity as well as perinatal morbidity and mortality. Historically, reports of potential fetal teratogenicity and hypoglycemic effects on the fetus contraindicated the use of oral hypoglycemic agents in pregnancies complicated with either type II diabetes mellitus (DM) or gestational diabetes mellitus (GDM). Recently, physicians increasingly prescribe newer generations of oral hypoglycemic agents to treat GDM and type II DM to pregnant patients. This review addresses the safety, current recommendations, and controversies surrounding use of the available oral hypoglycemic agents during pregnancy.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians

LEARNING OBJECTIVES

After completion of this article, the reader should be able to describe the mechanisms of actions of the various oral hypoglycemic agents, to list the known side effects of these agents, and to summarize the data on the use of these agents during pregnancy.

Detection of subsequent episodes of gestational diabetes mellitus: a need for specific guidelines

Guidelines for detection of individuals with gestational diabetes mellitus (GDM) indicate that glucose testing for women with a history of GDM should occur as soon as feasible with retesting of an initially negative screen to occur between the 24th and 28th week of gestation. The aim of this study was to evaluate medical records for individuals enrolled in a GDM management program that presented with two subsequent pregnancies with GDM and to determine if more specific guidelines for detection are needed. Records (n=60) from both pregnancies were reviewed for gestational age at enrollment, delivery, and when insulin was started, infant birth weights and complications (e.g., hypoglycemia), and maternal complications (e.g., emergency cesarean section). Over half [33/60 (55%)] of the women required insulin during both pregnancies, while 16.7% (10/60) required insulin during the second enrollment for GDM but not the first. For those requiring insulin during both pregnancies, 88% (29/33) required it earlier during the subsequent pregnancy (31.5+/-2.7 vs. 21.6+/-8.4 weeks of gestation, P<.001). During the subsequent pregnancy, approximately 1/2 of the women requiring insulin needed it before the 24th week of gestation while 1/3 required it by the 15th week. Also during the subsequent pregnancy, neonate birth weights declined (3494+/-521 vs. 3356+/-515 g, P<.05) and there were fewer complications. Given that approximately 70% of the women required insulin therapy during a subsequent GDM pregnancy and that this therapy was on average necessary by the 22nd week of gestation, we recommend that specific guidelines be established with a definitive time frame determined for the detection of repeat episodes of GDM.

Epidemiology of gestational diabetes mellitus and its association with Type 2 diabetes

Gestational diabetes (GDM) is defined as carbohydrate intolerance that begins or is first recognized during pregnancy. Although it is a well-known cause of pregnancy complications, its epidemiology has not been studied systematically. Our aim was to review the recent data on the epidemiology of GDM, and to describe the close relationship of GDM to prediabetic states, in addition to the risk of future deterioration in insulin resistance and development of overt Type 2 diabetes. We found that differences in screening programmes and diagnostic criteria make it difficult to compare frequencies of GDM among various populations. Nevertheless, ethnicity has been proven to be an independent risk factor for GDM, which varies in prevalence in direct proportion to the prevalence of Type 2 diabetes in a given population or ethnic group. There are several identifiable predisposing factors for GDM, and in the absence of risk factors, the incidence of GDM is low. Therefore, some authors suggest that selective screening may be cost-effective. Importantly, women with an early diagnosis of GDM, in the first half of pregnancy, represent a high-risk subgroup, with an increased incidence of obstetric complications, recurrent GDM in subsequent pregnancies, and future development of Type 2 diabetes. Other factors that place women with GDM at increased risk of Type 2 diabetes are obesity and need for insulin for glycaemic control. Furthermore, hypertensive disorders in pregnancy and afterwards may be more prevalent in women with GDM. We conclude that the epidemiological data suggest an association between several high-risk prediabetic states, GDM, and Type 2 diabetes. Insulin resistance is suggested as a pathogenic linkage. It is possible that improving insulin sensitivity with diet, exercise and drugs such as metformin may reduce the risk of diabetes in individuals at high risk, such as women with polycystic ovary syndrome, impaired glucose tolerance, and a history of GDM. Large controlled studies are needed to clarify this issue and to develop appropriate diabetic prevention strategies that address the potentially modifiable risk factors.

Inflammation and glucose intolerance: a prospective study of gestational diabetes mellitus

OBJECTIVE

Increased leukocyte count is a marker of inflammation that has been associated with the development of type 2 diabetes in prospective studies. Although gestational diabetes mellitus (GDM) and type 2 diabetes share certain pathophysiological mechanisms, few studies have examined inflammation and risk of GDM.

RESEARCH DESIGN AND METHODS

We prospectively examined routine leukocyte counts collected at the first prenatal visit in a cohort of 2,753 nulliparous euglycemic women, 98 (3.6%) of whom were later diagnosed with GDM. Subjects were divided into quartiles of leukocyte count, and the results of third-trimester glucose screening tests and the incidence of GDM among these quartiles were compared. Logistic regression was used to calculate univariate and multivariable-adjusted relative risks (RRs) of GDM according to leukocyte quartiles.

RESULTS

Leukocyte counts were increased among women who subsequently developed GDM compared with those who remained free of GDM (10.5 +/- 2.2 vs. 9.2 +/- 2.2 x 10(3) cells/ml; P < 0.01). There was a linear increase in postloading mean glucose levels (P for trend <0.01), the area under the glucose tolerance test curves (P for trend <0.01), and the incidence of GDM (quartile 1, 1.1; quartile 2, 2.5; quartile 3, 4.2; and quartile 4, 6.4%; P for trend <0.01) with increasing leukocyte quartiles. In the multivariable-adjusted analysis, the linear trend in the RR of GDM with increasing leukocyte quartiles remained statistically significant (quartile 1, reference; quartile 2, RR 2.3 [95% CI 0.9-5.7]; quartile 3, 3.3 [1.4-7.8]; quartile 4, 4.9 [2.1-11.2]; P for trend <0.01).

CONCLUSIONS

Increased leukocyte count early in pregnancy is independently and linearly associated with the results of GDM screening tests and the risk of GDM. Although overlap in the leukocyte count distributions precludes it from being a clinically useful biomarker, these data suggest that inflammation is associated with the development of GDM and may be another pathophysiological link between GDM and future type 2 diabetes.

Admissions to neonatal intensive care unit following pregnancies complicated by gestational or type 2 diabetes

BACKGROUND

When gestational diabetes mellitus (GDM) is diagnosed in a population with a high prevalence of unrecognised type 2 diabetes mellitus (type 2 DM), the rate of neonatal morbidity is not clear. There is also a paucity of data reporting neonatal outcome in women with recognised type 2 DM.

AIM

To describe, in a population with a high background prevalence of type 2 DM, neonatal morbidity in infants of women with GDM and type 2 DM admitted to the neonatal intensive care unit (NICU).

METHODS

A 2-year audit was carried out in a tertiary level obstetric hospital with a multi-ethnic delivery population. All infants admitted to the NICU whose mothers had GDM or type 2 DM were identified from the hospital database. The records of 136 infants were retrospectively reviewed and data collected on outcome measures including maternal diagnosis, macrosomia, mode of delivery, delivery complications, hypoglycaemia, respiratory distress and congenital anomalies.

RESULTS

Admission to NICU occurred in 29% of GDM and 40% of type 2 DM pregnancies. Median gestation was 37 weeks (range: 25-41), with 46% delivered preterm. Forty percent of infants were delivered by emergency Caesarean section. Fifty-one percent of admissions had hypoglycaemia and 40% required support for respiratory distress. Women with type 2 DM diagnosed either prepregnancy or post-partum were the highest risk group for neonatal morbidity, including congenital anomalies.

CONCLUSIONS

Neonatal morbidity is common in infants of women with type 2 DM and GDM in a population with high prevalence of type 2 DM.

Cigarette smoking and the risk of gestational and pregestational diabetes in two consecutive pregnancies

OBJECTIVE

Cigarette smoking during pregnancy may increase the risk of gestational diabetes mellitus (GDM) or pregestational diabetes mellitus (PDM). Smoking has been associated positively with hyperinsulinemia and insulin resistance in experimental studies, although the association with diabetes remains unclear. To further explore this issue, we examined the association with smoking in the largest prospective cohort study of GDM and PDM to date.

RESEARCH DESIGN AND METHODS

The study population comprised 212190 women in the population-based Swedish Birth Registry who had their first and second deliveries between January 1987 and December 1995. Maternal characteristics were recorded in a standardized manner at the first prenatal visit, followed by a clinical examination and a standardized in-person interview to assess lifestyle habits. Women were categorized as nonsmokers, light smokers (one to nine cigarettes per day), or moderate-to-heavy smokers (at least 10 cigarettes per day).

RESULTS

Women with GDM in their first pregnancy experienced an eight- to ninefold increased risk of GDM or PDM in their second pregnancy. Cigarette smoking was not associated with increased risk of these conditions. Neither women who smoked during their first and second pregnancies nor those who commenced smoking between pregnancies had a higher risk of GDM or PDM than nonsmokers.

CONCLUSIONS

Our findings do not support an association between cigarette smoking and risk of GDM or PDM in young women of childbearing age.

Insulin gene VNTR genotype is associated with insulin sensitivity and secretion in infancy

AIMS

We have previously demonstrated that insulin sensitivity and secretion at age 1 year was in part related to variation in weight and height gain during infancy. In order to determine whether genetic variation at the insulin gene could also influence these associations, we have studied the relationship between insulin gene variable number of tandem repeat (INS VNTR) genotypes, insulin secretion and early postnatal growth.

METHODS

We assessed fasting and dynamic insulin secretion in 99 healthy infants at age 1 year, using a short intravenous glucose tolerance test (sIVGTT). Infants were genotyped at the -23 HphI locus, as a surrogate marker for INS VNTR allele classes I and III. Anthropometric data were recorded at birth and at 1 year. Data are shown as median (interquartile range).

RESULTS

Fasting insulin levels were higher in III/III infants (n = 9) than in I/I infants [n = 55; 27.4 (17.6-75.6) pmol/l vs. 18.1 (10.3-25.2) pmol/l; P < 0.05]. Insulin secretion during the sIVGTT, as estimated by the serum insulin area under the curve, was also higher in III/III infants [2417 (891-4041) pmol min/l vs. 1208 (592-2284) pmol min/l; P < 0.05]. Fasting and postload plasma glucose levels were similar in both groups. Analysis of covariance showed that genotype differences in fasting insulin sensitivity and insulin secretion were independent of size at birth, postnatal growth velocity and current body mass index.

CONCLUSIONS

Significant associations between INS VNTR genotype and both insulin sensitivity and secretion were apparent in infancy; these might interact with childhood appetite and nutrition to impact the development of childhood obesity and insulin resistance.

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).

Impaired fasting glucose and impaired glucose tolerance in women with prior gestational diabetes are associated with a different cardiovascular profile

OBJECTIVE

The purpose of this study was to investigate the association of cardiovascular risk factors to impaired glucose tolerance (IGT) and to impaired fasting glucose (IFG) in women with prior gestational diabetes mellitus (GDM).

RESEARCH DESIGN AND METHODS

We studied 838 women with prior GDM. Postpartum glucose tolerance status was classified as normal, IFG, IGT, IFG plus IGT, and diabetes according to the World Health Organization criteria. Postpartum BMI, waist circumference, blood pressure, triglyceride, cholesterol, and HDL cholesterol were assessed.

RESULTS

BMI and blood pressure were significantly higher in women with IFG than in women with normal glucose status. BMI and waist circumference were significantly higher in women with IFG plus IGT than in women with normal glucose status. No differences were observed between women with IGT and normal glucose status. The prevalence of hypertension and obesity was significantly increased in IFG compared with normal glucose status. The prevalence of obesity and abnormal lipids was significantly increased in IFG plus IGT compared with normal glucose status. IGT showed no increased prevalence of cardiovascular risk factors.

CONCLUSIONS

Traditional cardiovascular risk factors have a stronger association with isolated IFG than with isolated IGT in women with prior GDM.

Continuous glucose monitoring for treatment adjustment in diabetic pregnancies--a pilot study

AIMS

To examine the efficacy of a continuous glucose monitoring (CGM) system for treatment adjustment in patients with diabetic pregnancy treated with insulin.

METHODS

The study sample consisted of eight women with diabetic pregnancy, six with pre-pregnancy Type 1 diabetes mellitus and two with gestational diabetes (GDM), all being treated with multiple daily insulin injections. Gestational age ranged from 24 to 32 weeks. Data derived from the Continuous Glucose Monitoring System (MiniMed) for 72 h were compared with fingerstick glucose measurements (six to eight times a day), and treatment was adjusted on the basis of the findings. Two to four weeks later, the patients were re-evaluated with CGM.

RESULTS

In the first part of the study, an average of 744+/-33 glucose measurements was recorded for each patient with CGM. The mean total time of hyperglycaemia (glucose level >7.7 mmol/l) undetected by the fingerstick method was 152+/-33 min/day. Nocturnal hypoglycaemic events (glucose level <2.7 mmol/l) were recorded in seven patients. Based on the additional information obtained by continuous monitoring, the insulin regimen was changed in all patients. CGM re-evaluation after treatment adjustment showed a reduction in undetected hyperglycaemia to 89+/-17 min/day and in nocturnal hypoglycaemic events, which were recorded in only one patient.

CONCLUSIONS

Continuous glucose monitoring may diagnose high blood glucose levels and nocturnal hypoglycaemic events that are unrecognized by intermittent blood glucose monitoring and could serve as a useful tool for the long-term management of diabetic pregnancies. A large prospective study is needed to determine the clinical implications of this new monitoring technique.

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.

Maternal-fetal transport of hypoglycaemic drugs

Due to legal, ethical and monetary problems, drug studies in pregnancy are rare. Numerous pharmacokinetic and pharmacodynamic changes occur in pregnancy that can affect the efficacy and safety of drugs, and these are difficult to predict without appropriate studies. Drugs potentially useful and safe in pregnancy have to either not cross the placenta and/or be harmless to the fetus at clinically relevant concentrations. The first characteristic can be predicted using in vitro models such as the placenta perfusion model. In the case of glibenclamide (glyburide), in vitro experiments showed minimal maternal-fetal transfer, leading to completion of a successful clinical trial of this drug in gestational diabetes. Insulin, the main drug used in diabetes during pregnancy, has also been shown not to cross the placenta in vitro, as has insulin lispro. Animal insulin may cross the placenta when complexed with anti-insulin antibodies. Other sulphonylurea drugs (tolbutamide and chlorpropamide) have been shown to cross the placenta both in vitro and in vivo and to produce toxicity in the fetus. This review summarises the pharmacokinetic data available for hypoglycaemic drugs during pregnancy, as well as the potential role for the in vitro placenta perfusion model in the preclinical evaluation of drugs with potential usefulness in pregnancy.

[Occurrence of diabetes mellitus in women with prior gestational hyperglycemia]

OBJECTIVE

To estimate the prevalence of glucose intolerance (diabetes mellitus and impaired glucose tolerance) in women who had their glucose tolerance evaluated and followed up during pregnancy.

METHODS

Over the last 12 years since the index pregnancy, from a total of 3,113 pregnant women seen in an obstetrics clinic, 551 were randomly selected and proportionally to the number of women in each group. Of these, 529 could be evaluated and had been classified as follows: 250 in group IA (normal glucose tolerance); 120 in group IB (daily hyperglycemia); 72 in group IIA (abnormal oral glucose tolerance test); and 87 in group IIB (abnormal oral glucose tolerance test and daily hyperglycemia). The evaluation consisted of measuring fasting plasma glucose and when the results ranged between 6.1 and 6.9 mmol/L, patients were submitted to oral glucose tolerance test.

RESULTS

Prevalence of diabetes mellitus was: IA, 1.6%; IB, 16.7%; IIA, 23.6%; and IIB, 44.8% (IA < [IB = IIA] < IIB; p<0.05). This difference between the groups remained the same for the eight years. Women in IA group were different from others regarding age, parity, and diabetes family history.

CONCLUSION

Hyperglycemia (high plasma glucose levels) and abnormal oral glucose tolerance test during pregnancy are equally effective in predicting the risk for developing maternal diabetes. When both tests are abnormal, this risk is much higher.

Maternal gestational diabetes, birth weight, and adolescent obesity

OBJECTIVE

Obesity increases risk of many adverse outcomes, but its early origins are obscure. Gestational diabetes mellitus (GDM) reflects a metabolically altered fetal environment associated with high birth weight, itself associated with later obesity. Previous studies of GDM and offspring obesity, however, have been few and conflicting. The objectives of this study were to examine associations of birth weight and GDM with adolescent body mass index (BMI) and to determine the extent to which the effect of GDM is explained by its influence on birth weight or by maternal adiposity.

METHODS

We conducted a survey of 7981 girls and 6900 boys, 9 to 14 years of age, who are participants in the Growing Up Today Study, a US nationwide study of diet, activity, and growth. In 1996, participants reported height, weight, diet, activity, and other variables by self-administered mailed questionnaire. We linked these data with information reported by their mothers, participants in the Nurses' Health Study II, including GDM, height, current weight, and child's birth weight. We excluded births <34 weeks' gestation and mothers who had preexisting diabetes. We defined overweight as BMI (kg/m(2)) >95th percentile, and at risk for overweight as 85th to 95th percentile, for age and gender from US national data.

RESULTS

Mean birth weight was 3.4 kg for girls and 3.6 kg for boys. Among the 465 subjects whose mothers had GDM, 17.1% were at risk for overweight and 9.7% were overweight in early adolescence. In the group without maternal diabetes, these estimates were 14.2% and 6.6%, respectively. In multiple logistic regression analysis, controlling for age, gender, and Tanner stage, the odds ratio for adolescent overweight for each 1-kg increment in birth weight was 1.4 (95% confidence interval: 1.2-1.6). Adjustment for physical activity, television watching, energy intake, breastfeeding duration, mother's BMI, and other maternal and family variables reduced the estimate to 1.3 (1.1-1.5). For offspring of mothers with GDM versus no diabetes, the odds ratio for adolescent overweight was 1.4 (1.1-2.0), which was unchanged after controlling for energy balance and socioeconomic factors. Adjustment for birth weight slightly attenuated the estimate (1.3; 0.9-1.9); adjustment for maternal BMI reduced the odds ratio to 1.2 (0.8-1.7).

CONCLUSIONS

Higher birth weight predicted increased risk of overweight in adolescence. Having been born to a mother with GDM was also associated with increased adolescent overweight. However, the effect of GDM on offspring obesity seemed only partially explained by its influence on birth weight, and adjustment for mother's own BMI attenuated the GDM associations. Our results only modestly support a causal role of altered maternal-fetal glucose metabolism in the genesis of obesity in the offspring. Alternatively, GDM may program risk for a postnatal insult leading to obesity, or it may merely be a risk marker, not in the causal pathway.

Increased intramyocellular lipid concentration identifies impaired glucose metabolism in women with previous gestational diabetes

Women with previous gestational diabetes (pGDM) are frequently insulin-resistant, which could relate to intramyocellular lipid content (IMCL). IMCL were measured with (1)H nuclear magnetic resonance spectroscopy in soleus (IMCL-S) and tibialis-anterior muscles (IMCL-T) of 39 pGDM (32 +/- 2 years, waist-to-hip ratio 0.81 +/- 0.01) and 22 women with normal glucose tolerance (NGT; 31 +/- 1 years, 0.76 +/- 0.02) at 4-6 months after delivery. Body fat mass (BFM) was assessed from bioimpedance analysis, insulin sensitivity index (S(I)), and glucose effectiveness (S(G)) from insulin-modified frequently sampled glucose tolerance tests. pGDM exhibited 45% increased BFM, 35% reduced S(I) and S(G) (P < 0.05), and 40% (P < 0.05) and 55% (P < 0.005) higher IMCL-S and IMCL-T, respectively. IMCL related to body fat (BFM P < 0.005, leptin P < 0.03), but only IMCL-T correlated (P < 0.03) with S(I) and glucose tolerance index independent of BMI. Insulin-resistant pGDM (n = 17) had higher IMCL-S (+66%) and IMCL-T (+86%) than NGT and insulin-sensitive pGDM (+28%). IMCL were also higher (P < 0.005, P = 0.05) in insulin-sensitive pGDM requiring insulin treatment during pregnancy and inversely related to the gestational week of GDM diagnosis. Thus, IMCL-T reflects insulin sensitivity, whereas IMCL-S relates to obesity. IMCL could serve as an additional parameter of increased diabetes risk because it identifies insulin-resistant pGDM and those who were diagnosed earlier and/or required insulin during pregnancy.

Proposed diagnostic thresholds for gestational diabetes mellitus according to a 75-g oral glucose tolerance test. Maternal and perinatal outcomes in 3260 Danish women

AIMS

To study if established diagnostic threshold values for gestational diabetes based on a 75-g, 2-h oral glucose tolerance test can be supported by maternal and perinatal outcomes.

METHODS

Historical cohort study of 3260 pregnant women examined for gestational diabetes on the basis of risk indicators. Information on oral glucose tolerance test results and clinical outcomes were collected from medical records.

RESULTS

There was an increased risk of delivering a macrosomic infant in women with 2-h capillary blood glucose of 7.8-8.9 mmol/l compared with women with 2-h glucose < 7.8 mmol/l. Despite treatment, 2-h glucose of 9.0-11.0 mmol/l and > or = 11.1 mmol/l were both associated with increased rates of macrosomia, spontaneous preterm delivery, hypertensive complications, and neonatal hypoglycaemia. Adverse outcomes tended to be more frequent in women with 2-h glucose > or = 11.1 mmol/l than in women with 2-h glucose of 9.0-11.0 mmol/l.

CONCLUSIONS

The risk for several maternal and perinatal complications increased with the diagnostic threshold for 2-h glucose. Large-scale blinded studies are needed to clarify the question of a clinically meaningful diagnosis of gestational diabetes mellitus. Until these results are available, a 2-h threshold level of 9.0 mmol/l after a 75-g oral glucose tolerance test seems acceptable.

Fetal cyclic motor activity in diabetic pregnancies: sensitivity to maternal blood glucose

Spontaneous fetal movement in the last third of human gestation is dominated by irregular oscillations on a scale of minutes (cyclic motility, CM). The core properties of these oscillations are stable during the third trimester of gestation in normal fetuses, but disrupted by poorly controlled maternal diabetes. Here we investigated whether fetal CM is linked to short-term instabilities in maternal glucose metabolism. The fetuses of 40 mothers with type I (n = 28) or gestational (n = 12) diabetes were studied one to six times between 27 and 40 postmenstrual weeks of gestation. Fetal movement and maternal blood glucose concentration were measured during two separate periods of fetal activity in each session. Fetal CM was quantified with spectral analysis. Early in the third trimester, changes in the rate of oscillation in fetal CM between the two periods of activity were inversely related to changes in maternal blood glucose levels. Fetal CM was unrelated to concurrent maternal blood glucose levels at any point in the third trimester. The pattern of results suggests that disruption of the temporal organization of spontaneous fetal motor activity in pregnancies complicated by maternal diabetes represents an acute response to fluctuations in the metabolic environment rather than an alteration of CM development.

Gestational diabetes in Victoria in 1996: incidence, risk factors and outcomes

OBJECTIVES

To describe the epidemiology of gestational diabetes mellitus (GDM) in Victoria.

STUDY DESIGN

Population study of all women having singleton births in Victoria in 1996.

METHODS

Probabilistic record linkage of routinely collected data and capture-recapture techniques to provide an estimate of the incidence of GDM.

MAIN OUTCOME MEASURES

Risk factors for and the adverse outcomes associated with GDM compared with the non-diabetic population by univariate and multivariate analysis.

RESULTS

The estimated incidence of GDM was 3.6% (95% confidence interval [CI], 3.60%-3.64%). GDM is associated with women who are older, Aboriginal, non-Australian born, or who give birth in a larger hospital. The adverse outcomes associated with GDM pregnancies were hypertension/pre-eclampsia (adjusted odds ratio [OR], 1.6; 95% CI, 1.4-1.9), hyaline membrane disease (1.6; 1.2-2.2), neonatal jaundice (1.4; 1.2-1.7) and macrosomia (2.0; 1.8-2.3). Interventions during childbirth were also associated with GDM - for example, induction of labour (3.0; 2.7-3.4) and caesarean section (1.7; 1.6-1.9).

CONCLUSION

Women with GDM had increased rates of hypertension, pre-eclampsia, induced labour, and interventional delivery. Their offspring had a higher risk of macrosomia, neonatal jaundice and hyaline membrane disease.

Prevalence of gestational diabetes mellitus detected by the national diabetes data group or the carpenter and coustan plasma glucose thresholds

OBJECTIVE

In 2000, the American Diabetes Association proposed the adoption of the Carpenter and Coustan criteria for diagnosis of gestational diabetes mellitus (GDM). The Carpenter and Coustan cutoffs are lower than the previously recommended National Diabetes Data Group (NDDG) values and would result in higher prevalence of GDM. Our aim is to estimate the magnitude of change in prevalence of GDM using the Carpenter and Coustan thresholds as compared with the NDDG thresholds by age and ethnicity.

RESEARCH DESIGN AND METHODS

Cross-sectional study of 28,330 women aged 14-49 years who gave birth in 1996 and were members of the Northern California Kaiser Permanente Medical Care Program. Age, ethnicity, screening, and diagnostic test results were assessed from computerized hospitalization and laboratory systems.

RESULTS

A total of 26,481 (94%) women were screened using a 50-g, 1-h oral glucose tolerance test, and 4,190 women underwent a diagnostic 100-g, 3-h oral glucose tolerance test after an abnormal screening. Overall, the GDM prevalence among screened women was 3.2% (95% CI 3.0-3.4) by NDDG and 4.8% (95% CI 4.5-5.1) by Carpenter and Coustan criteria, and based on either threshold, it increased with age (P < 0.001). The age-adjusted GDM prevalence by NDDG and Carpenter and Coustan criteria, respectively, was 5.0 and 7.4% in Asians, 3.9 and 5.6% in Hispanics, 3.0 and 4.0% in African-Americans, and 2.4 and 3.8% in whites. Proportional increments were larger in women aged <25 years (70%) and in whites (58%).

CONCLUSIONS

-The prevalence of GDM increased, on average, by 50% with use of the Carpenter and Coustan thresholds. Relative increments were greater in low-risk age and ethnic groups. This information would be useful for clinical settings in predicting cost of GDM based on demographic characteristics of the population.

Current controversies in the mechanisms and treatment of gestational diabetes

Gestational diabetes mellitus (GDM) is a heterogeneous entity, including carbohydrate intolerance of variable severity with onset or first recognition during pregnancy. Insulin resistance and beta-cell dysfunction are thought to be major determinants of its development. Its pathomechanism in many ways resembles that of type 2 diabetes. There is an evolving body of evidence from the last decade presenting similarities between gestational diabetes and the metabolic (insulin resistance) syndrome. These new observations suggest that GDM might be an early manifestation of the metabolic syndrome. The desired treatment target of GDM is normoglycemia. It can be reached by dietary treatment; however, if it fails, maternal glycemic monitoring or combined fetal-maternal monitoring, or even insulin (if required) can help reach it. Multiple daily insulin regimens are becoming more widely accepted for the treatment of GDM. Insulin analogues, however, need some more evidence to support their usefulness and safety during pregnancy. The screening for GDM, the reclassification, regular care, and follow-up of these women after pregnancy are of the utmost importance to delay or prevent not only type 2 diabetes but cardiovascular complications as well.