Peripartum metabolic control in gestational diabetes

Insulin Management for Gestational and Type 2 Diabetes in Pregnancy

Insulin is preferred as the first-line agent for glucose management of gestational diabetes mellitus and type 2 diabetes in pregnancy when nutritional and lifestyle modifications are unable to achieve pregnancy-specific glucose targets. Individual heterogeneity in defects of insulin secretion or sensitivity in liver and muscle, unique genetic influences on pregnancy glycemic regulation, and variable cultural and lifestyle behaviors that affect meal, activity, sleep, and occupational schedules necessitate a personalized approach to insulin regimens. Newer insulin preparations have been developed to mimic the physiologic release of endogenous insulin, maintaining appropriate basal levels to cover hepatic gluconeogenesis and simulate the rapid, meal-related, bolus rise of insulin. Such physiologic basal-bolus dosing of insulin can be administered safely, achieving tighter glycemic control while reducing episodes of hypoglycemia. Insulin initiation and titration require understanding the pharmacodynamics of different insulin preparations in addition to a patient's glycemic profiles, effect of variable nutritional intake and mealtimes, physical activity, stress, timing of sleep cycles, and cultural habits. Educating and empowering patients to learn how their glucose responds to insulin, portion and content of meals, and physical activity can increase personal engagement in therapy, flexibility in eating patterns, and improved glycemic control. This Clinical Expert Series article is focused on optimizing insulin management (initiation, dosing, and titration) of gestational and type 2 diabetes in pregnancy.

Intrapartum maternal glycaemic control for the prevention of neonatal hypoglycaemia: a systematic review and meta-analysis

BACKGROUND

Neonatal hypoglycaemia is the most common metabolic disorder in infants, and may be influenced by maternal glycaemic control. This systematic review evaluated the effect of intrapartum maternal glycaemic control on neonatal hypoglycaemia.

METHODS

We included randomised controlled trials (RCTs), quasi-RCTs, non-randomised studies of interventions, and cohort or case-control studies that examined interventions affecting intrapartum maternal glycaemic control compared to no or less stringent control. We searched four databases and three trial registries to November 2023. Quality assessments used Cochrane Risk of Bias 1 or the Effective Public Health Practice Project Quality Assessment Tool. Certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE). Meta-analysis was performed using random-effects models analysed separately for women with or without diabetes. The review was registered prospectively on PROSPERO (CRD42022364876).

RESULTS

We included 46 studies of women with diabetes and five studies of women without diabetes: one RCT, 32 cohort and 18 case-control studies (11,273 participants). For women with diabetes, the RCT showed little to no difference in the incidence of neonatal hypoglycaemia between tight versus less tight intrapartum glycaemic control groups (76 infants, RR 1.00 (0.45, 2.24), p = 1.00, low certainty evidence). However, 11 cohort studies showed tight intrapartum glycaemic control may reduce neonatal hypoglycaemia (6,152 infants, OR 0.44 (0.31, 0.63), p < 0.00001, I2 = 58%, very low certainty evidence). For women without diabetes, there was insufficient evidence to determine the effect of tight intrapartum glycaemic control on neonatal hypoglycaemia.

CONCLUSIONS

Very uncertain evidence suggests that tight intrapartum glycaemic control may reduce neonatal hypoglycaemia in infants of women with diabetes. High-quality RCTs are required.

Insulin Use During Gestational and Pre-existing Diabetes in Pregnancy: A Systematic Review of Study Design

INTRODUCTION

Insulin is the first-line pharmacologic therapy for women with diabetes in pregnancy. However, conducting well-designed randomized clinical trials (RCTs) and achieving recommended glycemic targets remains a challenge for this unique population. This systematic literature review (SLR) aimed to understand the evidence for insulin use in pregnancy and the outcome metrics most often used to characterize its effect on glycemic, maternal and fetal outcomes in gestational diabetes mellitus (GDM) and in pregnant women with diabetes.

METHODS

An SLR was conducted using electronic databases in Medline, EMBASE via Ovid platform, evidence-based medicine reviews (2010-2020) and conference proceedings (2018-2019). Studies were included if they assessed the effect of insulin treatment on glycemic, maternal or fetal outcomes in women with diabetes in pregnancy. Studies on any type of diabetes other than gestational or pre-existing diabetes as well as non-human studies were excluded.

RESULTS

In women diagnosed with GDM or pre-existing diabetes, most studies compared treatment of insulin with metformin (n = 35) followed by diet along with lifestyle intervention (n = 24) and glibenclamide (n = 12). Most studies reporting on glycemic outcomes compared insulin with metformin (n = 22) and glibenclamide (n = 4). Fasting blood glucose was the most reported clinical outcome of interest. Among the studies reporting maternal outcomes, method of delivery and delivery complications were most commonly reported. Large for gestational age, stillbirth and perinatal mortality were the most common fetal outcomes reported.

CONCLUSION

This SLR included a total of 108 clinical trials and observational studies with diverse populations and treatment arms. Outcomes varied across the studies, and a lack of consistent outcome measures to manage diabetes in pregnant women was observed. This elucidates a need for global consensus on study design and standardized clinical, maternal and fetal outcomes metrics.

Gestational diabetes mellitus in association with macrosomia in Iran: a meta-analysis

PURPOSE

This meta-analysis aimed to estimate the association between gestational diabetes mellitus (GDM) and occurrence of macrosomia for the first time among Iranian population.

METHODS

A systematic review was done of national and international databases. Lists of relevant articles were checked to increase sensitivity of the search reference. Also, access to unpublished articles and documents were accessed by negotiation with related individuals and research centers. These published epidemiological studies (cross-sectional, case-control and cohort studies) were used for comparisons to determine whether GDM was associated with macrosomia. Finally, the Mantel-Haenszel method and the fixed and random-effect models based on heterogeneity of the primary studies were used according to pool results and estimate the odds ratio of macrosomia in women with GDM.

RESULTS

Of 1870 articles, thirty relevant articles were eligible for the current meta-analysis. Our findings showed that 335 of 2524 women with GDM had macrosomia while only 775 of 26,592 women without GDM had macrosomia. Using random-effect model, the pooled odds ratio (OR) relation between GDM and occurrence of macrosomia was estimated as of 5.49 (95% CI: 4.27-7.04). Subgroup analysis showed no difference regarding different study designs and definitions of macrosomia. There was no evidence of publication bias based on the result of Egger's test (β = 0.1, P = 0.70).

CONCLUSIONS

This meta-analysis shows that GDM is directly associated with the risk of macrosomia in the Iranian population. This confirms the findings of previous studies in the wider scientific literature.

Intrapartum glycaemic control and neonatal hypoglycaemia in pregnancies complicated by diabetes: a systematic review

AIMS

To examine whether, in neonates of mothers with Type 1, Type 2 and gestational diabetes, in-target intrapartum glycaemic control was associated with a lower risk of neonatal hypoglycaemia compared with out-of-target glycaemic control.

METHODS

We searched PubMed and EMBASE for all available publications, regardless of year, based on a published protocol (PROSPERO CRD42016052439). Studies were excluded if they did not report original data or were animal studies. Data were extracted from published reports in duplicate using a prespecified data extraction form. The main outcome of interest was the association between in-target intrapartum glycaemic control and neonatal hypoglycaemia.

RESULTS

We screened 2846 records for potential study inclusion; 23 studies, including approximately 2835 women with diabetes, were included in the systematic review. Only two of those studies specifically examined in-target vs out-of-target intrapartum glycaemic control. Of the studies included, six showed a relationship between intrapartum glucose and neonatal hypoglycaemia, five others showed a relationship in at least one of the analyses performed and 12 did not find a significant relationship. Only one study was identified as having a low risk of bias.

CONCLUSIONS

There is a paucity of high-quality data supporting the association of glucose during labour and delivery with neonatal hypoglycaemia in pregnancies complicated by diabetes. Further studies are required to examine the impact of tight glycaemic targets in labour.

Effects of uncomplicated vaginal delivery and epidural analgesia on fetal arterial acid-base parameters at birth in gestational diabetes

AIM

To investigate the effects of uncomplicated vaginal delivery and epidural analgesia on fetal acid-base parameters in women with gestational diabetes (GDM) compared with controls.

METHODS

A retrospective case-control study of 142 women with gestational diabetes and 284 controls. To evaluate the effect of diabetes and analgesia on acid-base status correcting for potential confounders we used ordered logistic equations including quartiles of fetal arterial acid-base parameters collected at birth as outcomes and categories of diabetes and epidural analgesia as explanatory variables.

RESULTS

In the GDM group cord base deficit (-2.63 mmol/l, interquartile range [IQR]=4.2 to -0.65 mmol/l vs. -1.9 mmol/l, IQR=-3.3 to -0.2 mmol/l, p=0.009, odds ratio (OR)=1.51, 95% confidence interval (CI)=1.04-2.18) was lower and concentration of calcium higher (1.49 mmol/l, IQR=1.42-1.56 mmol/l vs. 1.47 mmol/l, IQR=1.41-1.51 mmol/l, p=0.009, OR=1.69, 95% CI=1.12-2.56) compared with controls. Epidural analgesia in the GDM group was associated with reduced cord concentration of glucose (84.0mg/dl [4.7 mmol/l], IQR=70-103.3mg/dl vs. 92.5mg/dl [5.1 mmol/l], IQR=76.5-121.8 mg/dl, p=0.004), lactate (2.65 mmol/l (IQR=1.80-4.20) vs. 3.70 mmol/l (IQR=2.90-5.55 mmol/l), p=0.002) and less pronounced base deficit (-2.05 mmol/l, IQR=-3.90 to -0.17 mmol/l vs. -2.8, IQR=-5.57 to -1.05 mmol/l, p=0.01, OR=0.7, 95% CI=0.49-0.99).

CONCLUSIONS

In uncomplicated pregnancies and deliveries, well-controlled gestational diabetes mellitus has potentially significant detrimental effects on fetal acid-base status at birth. Epidural analgesia reduces cord arterial glucose and lactates.

Glucose control during labor and delivery

Neonatal hypoglycemia is an important consequence for the infant of the mother with diabetes. We have reviewed 24 published papers of various protocols for control of glucose in pregnant diabetic women during labor and delivery including our own published work. A relationship of maternal glucose during labor and neonatal hypoglycemia was sought in 19 of these studies. A significant inverse relationship was found in 10 reports with 3 others showing a similar trend. In all but 1 of these 13 studies the participants had pregestational diabetes. Three of the 6 studies not reporting an inverse relationship involved women with GDM. From this review it appears that the maternal glucose should be maintained between 4.0 and 6.0-7.0 mmol/L during labor. Most women with gestational diabetes, especially if they require <1.0 units/kg/d of insulin, can simply be monitored without intravenous insulin. Our own results demonstrate that a target glucose of 4.0-6.0 mmol/L can be used safely and results in a low rate of neonatal hypoglycemia using an iterative glucose insulin infusion protocol for women with pregestational diabetes and when needed for women with gestational diabetes.

Association between neonatal hypoglycaemia and prediabetes in postpartum women with a history of gestational diabetes

AIMS AND OBJECTIVES

To determine the association between hypoglycaemia among neonates born to mothers with gestational diabetes mellitus and their postpartum prediabetes.

BACKGROUND

Infants born to mothers with diabetes who experienced hyperglycaemia are more likely to develop hypoglycaemia.

DESIGN

A prospective-descriptive research was conducted in three tertiary hospitals in southern Thailand.

METHODS

One hundred and fifty matched pairs of mothers and their newborns were included in the study. Data were analysed using descriptive statistic, odds ratio, Spearman's rho correlation and binary logistic regression.

RESULTS

The incidence of neonatal hypoglycaemia was 42·37% and odds ratio was 0·30. The findings showed the significant association between neonatal hypoglycaemia and postpartum blood sugar levels of women with a history of gestational diabetes mellitus.

CONCLUSIONS

Neonatal hypoglycaemia was associated with maternal hyperglycaemia and prediabetes.

RELEVANCE TO CLINICAL PRACTICE

Neonatal hypoglycaemia might be used to predict prediabetes of postpartum women with a history of gestational diabetes mellitus.

[Gestational diabetes mellitus: importance of blood glucose monitoring]

Gestational diabetes mellitus (GDM) is common during pregnancy, and is frequently associated with maternal and perinatal complications. Intensive treatment of hyperglycaemia during pregnancy has been shown to reduce perinatal morbidity. In women with pregestational type 1 or 2 diabetes, hyperglycaemia during labour and delivery is an important factor in the development of neonatal hypoglycaemia. There are no generally accepted recommendations for women with GDM. Recent studies evaluating patients with GDM show that peripartum glucose control can be achieved in these women without the need for insulin use in the majority of cases. Hyperglycaemia during labour is not related with treatment established during pregnancy but rather with non-compliance of endocrinological follow-up. Factors such as ethnic origin, neonatal hypoxaemia, and large for gestational age seem to play an important role in the development of neonatal hypoglycaemia.

Gestational diabetes in a multiethnic population of Spain: clinical characteristics and perinatal outcomes

AIMS

To compare clinical characteristics and perinatal outcomes between immigrant and Spanish women with gestational diabetes mellitus (GDM) in a multiethnic population of Barcelona and to identify factors independently associated with the development of large-for-gestational-age (LGA) infants.

METHODS

Prospective study of women with GDM from five ethnic groups (Caucasian, South-Central Asian, Latin American, East Asian and Moroccan) at a single institution in Barcelona between 2004 and 2011. Maternal, gestational and newborn characteristics were recorded.

RESULTS

The cohort included 456 patients. In univariate analyses, Moroccan women had more frequently a pre-gestational body mass index (BMI)>25 kg/m(2) (76.4%, P=0.012), while East Asian women had lower BMI (23.41 ± 2.79 kg/m(2), P<0.001), less need for insulin therapy (14.3%, P=0.013) and the highest rate of spontaneous labor (69.8%, P=0.014) and eutocic delivery (63.8%, P=0.032). Also, Latin American women had a higher rate of Cesarean section (52.9%, P<0.001) and LGA infants (28.6%, P=0.004), and their newborns had lower umbilical cord pH (7.23 ± 0.06, P=0.005) and Apgar scores (9 [4-10], P<0.01) and a higher incidence of neonatal hypoglycemia (51.4%, P=0.045). Logistic regression analysis identified pre-gestational BMI (OR: 1.18; 95% CI: 1.09-1.27), pregnancy weight gain (OR: 1.19; 95% CI: 1.1-1.28) and insulin use during gestation (OR: 2.29; 95% CI: 1.09-4.82) as predictors of LGA infants.

CONCLUSIONS

Significant ethnic differences were found in clinical characteristics and perinatal outcomes of women with GDM. Latin American women had a higher frequency of adverse perinatal outcomes. Pregestational BMI, pregnancy weight gain and insulin use during pregnancy were independent predictors of LGA.

A prospective evaluation of neonatal hypoglycaemia in infants of women with gestational diabetes mellitus

OBJECTIVE

To analyse first-day-of-life glucose levels in infants of women with gestational diabetes (GDM) and the influence of maternal, gestational and peripartum factors on the development of neonatal hypoglycaemia.

STUDY DESIGN

Prospective cohort study including newborns of GDM mothers. Capillary blood glucose (CBG) was measured serially on the first day of life. CBG values were defined as normal (≥ 2.5 mmol/l), mild hypoglycaemia (2.2-2.4 mmol/l), moderate hypoglycaemia (1.6-2.1 mmol/l) and severe hypoglycaemia (<1.6 mmol/l).

RESULTS

One hundred and ninety infants were included: 23 (12.1%) presented mild, 20 (10.5%) moderate and only 5 (2.6%) severe hypoglycaemia. Hypoglycaemic infants were more frequently large-for-gestational-age (29.3% vs 11.3%, p=0.003), had lower umbilical cord pH (7.28 vs 7.31, p=0.03) and their mothers had more frequently been hyperglycaemic during labour (18.8% vs 8.5%, p=0.04). In multivariate analysis Pakistani origin (OR: 2.94; 95% CI: 1.14-7.55) and umbilical cord venous pH (OR: 0.04, 95% CI: 0.261-0.99) were significantly and independently associated with hypoglycaemia.

CONCLUSIONS

Mild and moderate neonatal hypoglycaemias were common although severe episodes were unusual in infants of women with GDM. Hypoglycaemia is mainly influenced by ethnicity and cord blood pH, although maternal peripartum glycaemic control and large-for-gestational-age condition may also play a role.