Management of diabetes in pregnancy: Antenatal follow-up and decisions concerning timing and mode of delivery

Diabetes during Pregnancy: A Maternal Disease Complicating the Course of Pregnancy with Long-Term Deleterious Effects on the Offspring. A Clinical Review

In spite of the huge progress in the treatment of diabetes mellitus, we are still in the situation that both pregestational (PGDM) and gestational diabetes (GDM) impose an additional risk to the embryo, fetus, and course of pregnancy. PGDM may increase the rate of congenital malformations, especially cardiac, nervous system, musculoskeletal system, and limbs. PGDM may interfere with fetal growth, often causing macrosomia, but in the presence of severe maternal complications, especially nephropathy, it may inhibit fetal growth. PGDM may also induce a variety of perinatal complications such as stillbirth and perinatal death, cardiomyopathy, respiratory morbidity, and perinatal asphyxia. GDM that generally develops in the second half of pregnancy induces similar but generally less severe complications. Their severity is higher with earlier onset of GDM and inversely correlated with the degree of glycemic control. Early initiation of GDM might even cause some increase in the rate of congenital malformations. Both PGDM and GDM may cause various motor and behavioral neurodevelopmental problems, including an increased incidence of attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). Most complications are reduced in incidence and severity with the improvement in diabetic control. Mechanisms of diabetic-induced damage in pregnancy are related to maternal and fetal hyperglycemia, enhanced oxidative stress, epigenetic changes, and other, less defined, pathogenic mechanisms.

Time trends in pregnancy-related outcomes among women with type 1 diabetes mellitus, 2004-2017

OBJECTIVE

To examine time trends in US pregnant women with type 1 diabetes mellitus for maternal characteristics and pregnancy outcomes.

STUDY DESIGN

We abstracted clinical data from the medical records of 700 pregnant women from 2004 to 2017. For each time period, means and percentages were calculated. P values for trend were calculated using linear and logistic regression.

RESULTS

HbA1c in each trimester was unchanged across the analysis period. The prevalence of nephropathy decreased from 4.8% to 0% (P = 0.002). Excessive gestational weight gain increased (P = 0.01). Gestation length also increased (P = 0.01), as did vaginal deliveries (P = 0.03). There were no change in birthweight over time (P = 0.07) and the percentage of neonates with macrosomia and large for gestational age (LGA) neonates also remained unchanged.

CONCLUSION

Obstetric guideline changes may have improved gestation length and mode of delivery; however, other outcomes need more attention, including excessive gestational weight gain, macrosomia, and LGA.

Diabetes: a metabolic and reproductive disorder in women

Reproductive dysfunction is a common but little studied complication of diabetes. The spectrum of reproductive health problems in diabetes is broad, and encompasses delayed puberty and menarche, menstrual cycle abnormalities, subfertility, adverse pregnancy outcomes, and potentially early menopause. Depending on the age at diagnosis of diabetes, reproductive problems can manifest early on in puberty, emerge later when fertility is desired, or occur during the climacteric period. Historically, women with type 1 diabetes have frequently had amenorrhoea and infertility, due to central hypogonadism. With the intensification of insulin therapy and improved metabolic control, these problems have declined, but do persist. Additional reproductive implications of contemporary diabetes management are now emerging, including polycystic ovary syndrome and hyperandrogenism, which are underpinned by insulin action on the ovary. The sharp rise in type 2 diabetes incidence in youth suggests that more women of reproductive age will encounter diabetes-related reproductive problems in their lifetimes. With an ever increasing number of young women living with diabetes, clinicians need to be aware of and equipped for the challenges of navigating reproductive health concerns across the lifespan.

Sonographic prediction of macrosomia in pregnancies complicated by maternal diabetes: finding the best formula

PURPOSE

To evaluate the best performing formula for macrosomia prediction in pregnancies complicated by diabetes.

METHODS

A retrospective analysis was performed of 1060 sonographic fetal biometrical measurements performed within 7 days of delivery in term pregnancies (37-42 gestational weeks) complicated by diabetes. Sonographic prediction of macrosomia (≥ 4000, ≥ 4250, and ≥ 4500 g) was evaluated utilizing ten previously published formulas by: (1) calculating for each macrosomia threshold the sensitivity, specificity, positive and negative predictive value, and ± likelihood ratio for macrosomia prediction; (2) comparing the systematic and random error and the proportion of estimates < 10% of birth weights between macrosomic and non-macrosomic neonates. Best performing formula was determined based on Euclidean distance.

RESULTS

97 (9.2%) macrosomic neonates (> 4000 g) were included. Median birth weight was 3380 (1866-3998) g for non-macrosomic and 4198 (4000-5180) g for macrosomic neonates. Higher macrosomia cutoff was associated with higher specificity and lower sensitivity. We found a considerable variation between formulas in different accuracy parameters. Hadlock's formula (1985), based on abdominal circumference, femur length, head circumference and biparietal diameter, had the shortest Euclidean distance, reflecting the highest accuracy.

CONCLUSION

Prediction of macrosomia among women with diabetes differs significantly between formulas. In our cohort, the best performing formula for macrosomia prediction was Hadlock's formula (1985).

Fourfold increase in prevalence of gestational diabetes mellitus after adoption of the new International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria

BACKGROUND

The aim was to evaluate the influence of the new International Association of Diabetes and Pregnancy Study Groups (IADPSG) guidelines for screening of gestational diabetes mellitus (GDM) on GDM prevalence in a cohort from a Swiss tertiary hospital.

METHODS

This was a retrospective cohort study involving all pregnant women who were screened for GDM between 24 and 28 weeks of gestation. From 2008 until 2010 (period 1), a two-step approach with 1-h 50 g glucose challenge test (GCT) was used, followed by fasting, 1- and 2-h glucose measurements after a 75 g oral glucose tolerance test (OGTT) in case of a positive GCT. From 2010 until 2013 (period 2), all pregnant women were tested with a one-step 75 g OGTT according to new IADPSG guidelines. In both periods, women with risk factors could be screened directly with a 75 g OGTT in early pregnancy.

RESULTS

Overall, 647 women were eligible for the study in period 1 and 720 in period 2. The introduction of the IADPSG criteria resulted in an absolute increase of GDM prevalence of 8.5% (3.3% in period 1 to 11.8% in period 2).

CONCLUSIONS

The adoption of the IADPSG criteria resulted in a considerable increase in GDM diagnosis in our Swiss cohort. Further studies are needed to investigate if the screening is cost effective and if treatment of our additionally diagnosed GDM mothers might improve short-term as well as long-term outcome.

Impact of type 2 diabetes, obesity and glycaemic control on pregnancy outcomes

BACKGROUND

There are no contemporary cohorts examining pregnancy outcomes in women with type 2 diabetes (T2D) in Australia.

AIM

To compare pregnancy outcomes in women with and without T2D, and assess effects of body mass index (BMI) and glycaemic control on outcomes.

MATERIALS AND METHODS

An historical cohort study was conducted of all singleton births > 20 weeks gestation at a specialist maternity network in Australia from 2010 to 2013. Data were extracted from the Birthing Outcomes System database. Multivariable logistic regression analysis was used to examine associations between presence of T2D and pregnancy outcomes.

RESULTS

Outcomes for 138 pregnancies with T2D and 27 075 pregnancies in women without diabetes were compared (type 1 diabetes and gestational diabetes excluded). Women with T2D were older and more overweight compared to women without diabetes (P < 0.01). Their babies were born earlier (P < 0.01) with increased risk of large for gestational age (adjusted odds ratio 2.13 (95% CI 1.37-3.32)), hypoglycaemia (4.90 (2.79-8.61)), jaundice (2.58 (1.61-4.13)) and shoulder dystocia (2.72 (1.09-6.78)), but not congenital malformations or perinatal death. Women with T2D had a higher risk of induction (4.03 (2.71-5.99)), caesarean section (2.10 (1.44-3.04)), preterm birth (2.74 (1.78-4.24)) and pre-eclampsia (2.75 (1.49-5.10)). An HbA1c ≥ 6.0% (42 mmol/mol) was associated with increased preterm birth, special care nursery admission, hypoglycaemia and jaundice.

CONCLUSIONS

Despite availability of preconception care, good glycaemic control and specialist management, T2D remains associated with increased adverse obstetric and neonatal outcomes. Further research to examine predictors of adverse outcomes may assist in targeted antenatal surveillance and management.