Effect of fetal hyperinsulinism on oral glucose tolerance test results in patients with gestational diabetes mellitus

Both glycaemic control and insulin dose during pregnancy in women with type 1 diabetes are associated with neonatal anthropometric measures and placental weight

BACKGROUND

To investigate longitudinal associations of maternal glucose/HbA_1c and insulin dose with birthweight-related outcomes in women with type 1 diabetes.

METHODS

We performed a cohort study including 473 pregnant women with type 1 diabetes with singleton pregnancies. We investigated maternal self-monitored blood glucose (SMBG, mmol/L), HbA_1c (%, mmol/mol) and insulin dose (IU/kg/day) in the three trimesters as potential independent variables, while adjusting for potential confounders. Outcomes of interest were birthweight, birthweight SD score, neonatal length, weight/length index, ponderal index and placental weight. Multiple linear regression analysis was performed with separate analyses for SMBG and HbA_1c .

RESULTS

Maternal glucose and insulin dose were independently associated with birthweight-related outcomes. In the main analysis, in the first trimester most associations were positive for insulin dose, in the second the associations were positive for glucose and inverse for insulin while in the third there were no associations. Most sensitivity analyses produced consistent results. In a sensitivity analysis splitting the first trimester in two periods, positive associations of maternal insulin with birthweight-related outcomes were observed in weeks 0+ to 6+.

CONCLUSIONS

Early in pregnancy in women with type 1 diabetes, maternal insulin dose is positively associated with birthweight-related outcomes, whereas in the second trimester, a positive association with SMBG emerges and the association with maternal insulin becomes inverse. If confirmed in other cohorts, these results would have implications in the management of women with type 1 diabetes.

The Utility of Lower Glycemic Targets for Treating Gestational Diabetes: A Retrospective Study

OBJECTIVE

In vivo study of glucose homeostasis in pregnancy suggests normal glucose levels are lower than current glycemic targets used in gestational diabetes. After the HAPO study results, our institution began using glycemic targets of fasting 85 mg/dL and 2-hour postprandial of 110 mg/dL. We reviewed our results.

METHODS

A retrospective cohort of GDM patients that delivered at KUMC from January 2007 to May 2017 was reviewed. All patients were diagnosed with the 2-step Carpenter-Coustan thresholds. High targets were compared with low targets. The primary outcome investigated was birthweight > 90% (large for gestational age, LGA).

RESULTS

604 patients were studied, and 34% were treated with low glycemic targets. Our unadjusted results showed that the low-target group had a lower incidence of LGA infants (24.0 vs. 31.8%), higher incidence of neonatal hypoglycemia (20.7 vs. 11.6%), and inductions (39.4 vs. 20.5%). After adjustment for demographic variables, only a higher risk of inductions remained (aOR 2.54 (1.44, 4.49)).

CONCLUSION

Lower glycemic targets did not produce large reductions in fetal overgrowth, but they were associated with a higher rate of inductions. As there were no observed differences in maternal or neonatal outcomes otherwise, aiming for lower glycemic targets in GDM is likely not cost-effective.

Correlation between plasma ferritin level and gestational diabetes mellitus and its impact on fetal macrosomia

Aims/Introduction

To explore the relationship between plasma iron levels and gestational diabetes mellitus, as well as its impact on macrosomia.

Materials and Methods

We retrospectively compared ferritin level and other characteristics between pregnant women with gestational diabetes mellitus (GDM) and pregnant women without GDM. The correlation between the levels of plasma ferritin, glucose and hemoglobin was explored. Meanwhile, we assessed the risk factors of macrosomia. Furthermore, we explored the relationship between ferritin level and the incidence of macrosomia.

Results

A total of 793 pregnant women were enrolled in the present study, of which 92 pregnant women had GDM and 701 pregnant women were healthy. Meanwhile, 51 pregnant women gave birth to infants with macrosomia and another 742 women had normal infants. Compared with non‐GDM women, pregnant women with GDM were older, with higher pre‐pregnancy body mass index, plasma ferritin, fasting plasma glucose, 1‐h postprandial glucose, 2‐h plasma glucose and hemoglobin. In addition, our results showed a significant positive correlation between the levels of ferritin and fasting plasma glucose when ferritin levels were >70 ng/mL. Our results also showed that pre‐pregnancy overweight or obesity, a high concentration of ferritin, as well as abnormal levels of fasting plasma glucose, 1‐h plasma glucose and 2 h plasma glucose were risk factors for macrosomia. Furthermore, as the level of ferritin increased, so did the incidence of macrosomia.

Conclusions

The current study provides evidence that pregnant women with high levels of ferritin might be prone to GDM. In addition, a high level of ferritin might be an independent risk factor for macrosomia. Therefore, the negative effect of iron supplementation in non‐anemic pregnant women might be noteworthy.

Short- and long-term consequences for offspring exposed to maternal diabetes: a review

The prevalence of gestational diabetes mellitus is increasing, as is the worldwide prevalence of type 2 diabetes and obesity, even in children and adolescents. Exposure in utero to maternal diabetes carries several short-term consequences due mainly to maternal hyperglycemia, and consequent fetal hyperinsulinemia. Current evidence also supports the hypothesis that adult health and disease have developmental origins, and that disorders in early-life environments prompt metabolic imprinting that results in a greater risk of negative metabolic outcomes later in life. In particular, exposure in utero to maternal diabetes seems to influence long-term metabolic outcomes, carrying a higher risk of obesity and type 2 diabetes, and thus creating a vicious cycle for future generations. In this paper, the short- and long-term consequences of exposure in utero to hyperglycemia are reviewed, focusing particularly on the long-term metabolic consequences, and investigating the possible pathogenic mechanisms involved.

The fetal glucose steal: an underappreciated phenomenon in diabetic pregnancy

Adverse neonatal outcomes continue to be high for mothers with type 1 and type 2 diabetes, and are far from eliminated in mothers with gestational diabetes mellitus. This is often despite seemingly satisfactory glycaemic control in the latter half of pregnancy. Here we argue that this could be a consequence of the early establishment of fetal hyperinsulinaemia, a driver that exaggerates the fetal glucose steal. Essentially, fetal hyperinsulinaemia, through its effect on lowering fetal glycaemia, will increase the glucose concentration gradient across the placenta and consequently the glucose flux to the fetus. While the steepness of this gradient and glucose flux will be greatest at times when maternal hyperglycaemia and fetal hyperinsulinaemia coexist, fetal hyperinsulinaemia will favour a persistently high glucose flux even at times when maternal blood glucose is normal. The obvious implication is that glycaemic control needs to be optimised very early in pregnancy to prevent the establishment of fetal hyperinsulinaemia, further supporting the need for pre-pregnancy planning and early establishment of maternal glycaemic control. An exaggerated glucose steal by a hyperinsulinaemic fetus could also attenuate maternal glucose levels during an OGTT, providing an explanation for why some mothers with fetuses with all the characteristics of diabetic fetopathy have 'normal' glucose tolerance.

Investigating the metabolic fingerprint of term infants with normal and increased fetal growth

An NMR metabolomic approach was employed to highlight the metabolic changes underlying prenatal disorders and determine metabolites that could serve as potential markers in relation to large for gestational age (LGA) newborns.

Second trimester maternal plasma and amniotic fluid adipokines in women who will develop gestational diabetes mellitus

OBJECTIVE

To study the adipokines concentration and glucose homoeostasis in the early-second trimester of women who will develop gestational diabetes mellitus (GDM).

MATERIALS AND METHODS

Maternal plasma and fetal amniotic fluid samples were prospectively collected between 2006 and 2007 at the time of mid-trimester amniocentesis. Eight patients found to be affected by GDM were compared with 10 control patients with a normal pregnancy course. Adipokines leptin and adiponectin, as well as insulin and glucose concentration both in amniotic fluid and maternal plasma were compared between cases and controls. HOMA-IR (homeostatic model assessment for insulin resistance) was also calculated both for amniotic fluid and maternal serum.

RESULTS

The amniotic fluid adiponectin concentration was higher in women who would develop GDM than in controls (29.9 ng/ml, 95% CI 26.7-49.8 ng/ml, versus 14.9 ng/ml, 95% CI 13.5-18.8 ng/ml), p < 0.05). No difference was shown for leptin both in amniotic fluid and maternal serum. Insulin concentrations in the amniotic fluid were found to be lower in GDM than in controls, while HOMA-IR-index resulted lower in amniotic fluid and higher maternal serum (p < 0.05).

CONCLUSIONS

Our data suggests that an earlier alteration in the fetal glucose metabolism will precede the glucose dysmetabolism in pregnancies later complicated by GDM.

Preventing and Treating Obesity in Girls and Young Women to Curb the Epidemic

Obesity and its serious comorbidities, type 2 diabetes, coronary heart disease, hypertension, and dyslipidemia, have reached epidemic proportions in adults and children. Female obesity is more prevalent and, thus, has greater epidemiological importance: mothers transmit the disease epigenetically and genetically. Maternal obesity affects maternal health, pregnancy outcome, and fetal, neonatal, childhood, and ultimately adult morbidity and mortality. Obesity is easy to diagnose, as are most of its risk factors, yet very little progress has been made in preventing the disease. During a brief period of rapid early growth, there is imprinting of antecedents of adult obesity and obesity-related disease. Because of the rapidity of this early growth and the relative brevity of the critical period, early recognition and prompt intervention are necessary and possibly sufficient to prevent the development of obesity. Identification of inappropriate rapid weight gain through frequent weighing should trigger immediate adjustment of energy intake, a simple intervention in bottle-fed infants, the ones at greatest risk for becoming obese. This review presents a step-care strategy with fail-safe action levels starting with maternal education and diet, exercise, and behavior modification for mother and child and progressing to drug treatment and, in selected cases, laparoscopic surgery for young women of childbearing age in whom other measures have failed. This approach is predicated on the assumption that careful monitoring and responsive supplementation of potential deficiencies is easier to achieve, more cost-effective, and safer than effectively treating manifest obesity and its comorbidities in adults.

Maternal glycemia and risk of large-for-gestational-age babies in a population-based screening

OBJECTIVE

Gestational diabetes is a risk factor for large-for-gestational-age (LGA) newborns, but many LGA babies are born to mothers with normal glucose tolerance. We aimed to clarify the association of maternal glycemia across the whole distribution with birth weight and risk of LGA births in mothers with normal glucose tolerance.

RESEARCH DESIGN AND METHODS

We undertook a population-based gestational diabetes screening in an urban area of Hungary in 2002-2005. All singleton pregnancies of mothers >or=18 years of age, without known diabetes or gestational diabetes (World Health Organization criteria) and data on a 75-g oral glucose tolerance test at 22-30 weeks of gestation, were included (n = 3,787, 78.9% of the target population). LGA was determined as birth weight greater than the 90th percentile using national sex- and gestational age-specific charts.

RESULTS

Mean +/- SD maternal age was 30 +/- 4 years, BMI was 22.6 +/- 4.0 kg/m(2), fasting blood glucose was 4.5 +/- 0.5 mmol/l, and postload glucose was 5.5 +/- 1.0 mmol/l. The mean birth weight was 3,450 +/- 476 g at 39.2 +/- 1.2 weeks of gestation. There was a U-shaped association of maternal fasting glucose with birth weight (P(curve) = 0.004) and risk of having an LGA baby (lowest values between 4 and 4.5 mmol/l, P(curve) = 0.0004) with little change after adjustments for clinical characteristics. The association of postload glucose with birth weight (P = 0.03) and the risk of an LGA baby (P = 0.09) was weaker and linear.

CONCLUSIONS

Both low and high fasting glucose values at 22-30 weeks of gestation are associated with increased risk of an LGA newborn. We suggest that the excess risk related to low glucose reflects the increased use of nutrients by LGA fetuses that also affects the mothers' fasting glucose.

Management of diabetes in pregnancy: comparison of guidelines with current practice at Austrian and Australian obstetric center

AIM

To compare Austrian and Australian national guidelines for gestational and pre-gestational diabetes and estimate the level to which physicians comply with their country's guidelines.

METHODS

Austrian (ODG, Austrian Diabetes Society) and Australian guidelines (ADIPS, Australasian Diabetes in Pregnancy Society) for the treatment of gestational diabetes and pre-gestational diabetes were systematically reviewed. Current practices in two obstetric centers in Austria and Australia were assessed by interviewing key stakeholders through questionnaires assessing different components of diabetes care. For gestational diabetes, these components were screening, abnormal oral glucose tolerance test values (mmol/L), abnormal values for diagnosis, further management when abnormal values are detected, monitoring/glucose targets (mmol/L), further management and indications for insulin therapy, route and timing of delivery, and postpartum management and counseling. For pre-gestational diabetes, the components were management during the preconceptional period, glucose target values, medical surveillance, obstetric surveillance, medication used, route and timing of delivery, and postpartum management and counseling.

RESULTS

More variation was found in the management of gestational than pre-gestational diabetes. There were differences in oral glucose tolerance test and cut-off levels for diagnosing gestational diabetes in both centers and guidelines. Australian guidelines recommended two-stage screening for gestational diabetes, while Austrian guidelines recommended one-stage screening. At the Austrian obstetric center, amniocentesis was recommended for determining the start of insulin treatment in pregnant women with gestational diabetes. This approach was neither used at the Australian obstetric center nor recommended by any of the two guidelines.

CONCLUSION

Our study showed that it was difficult to standardize screening criteria and diagnostic methods for gestational and pre-gestational diabetes. National and international consensus has yet to be achieved in the management of diabetes in pregnancy.

Clinical outcomes of pregnancy with one elevated glucose tolerance test value

OBJECTIVE

To evaluate clinical outcomes of pregnancies with one elevated glucose tolerance test.

METHODS

We performed a 50 g glucose challenge test (GCT) in 5,019 pregnant women at 24-28 weeks of gestation. In 1,170 women with plasma glucose levels over 130 mg/dl, a 100 g oral glucose tolerance test (OGTT) was performed at 28-32 weeks of gestation. During follow-up, 282 patients were lost and in the 888 cases that were followed-up, 189 were excluded because of GDM. Therefore 699 study patients were divided into four groups: No Elevated group (NE, N = 577) with all four normal 100 g OGTT values, and Groups 1 (N = 16), 2 (N = 35), and 3 (N = 71) with one elevated 100 g OGTT value after 1, 2 and 3 h, respectively.

RESULTS

Poor maternal outcomes (NE group, Group 1, Group 2, Group 3: 17.5%, 37.6%, 22.9%, 25.3%) with pre-eclampsia, cesarean delivery for cephalopelvic disproportion, failure to progress, or fetal distress, was highest in Group 1 (odds ratio 2.94; 95% confidence interval 1.02-8.42). Poor perinatal outcomes (15.8%, 43.1%, 14.3%, 21.1%) with any one of the following; fetal distress, Apgar score of < 7 at 5 min, hypoglycemia, respiratory distress syndrome, small for gestational age and perinatal death, was also highest in Group 1 (odds ratio 4.24; 95% confidence interval 1.02-17.52).

CONCLUSION

Pregnancies with one elevated glucose tolerance test value after 1 h exhibited increased adverse maternal and perinatal outcomes compared with the group with all normal OGTT values or the groups with an elevated glucose tolerance test value after 2 or 3 h.