Need for less tight glucose control in early pregnancy after embryogenesis due to high risk of maternal hypoglycaemia in women with pre-existing diabetes can be compensated by good control in late pregnancy

Pregnancy outcomes in type 2 diabetes: a systematic review and meta-analysis

OBJECTIVE

Type 2 diabetes (T2D) now accounts for the majority of pre-existing diabetes affecting pregnancy in the UK. Our aim was to determine its impact on pregnancy outcomes compared to type 1 diabetes (T1D), gestational diabetes (GDM), and nondiabetes pregnancies.

DATA SOURCES

PubMed was searched 1 January 2009 to 2024.

STUDY ELIGIBILITY CRITERIA

Cohort observational studies reporting original data on at least one of the primary outcomes in ten or more T2D pregnancies were eligible for inclusion. Comparative diabetes and nondiabetes pregnancies were also collected.

METHODS

Primary outcomes included congenital anomalies, stillbirths, neonatal and perinatal mortality, birthweight, rates of large for gestational age (LGA), small for gestational age (SGA), and macrosomia. PROSPERO ID CRD42023411057.

RESULTS

Forty seven studies were analyzed. The number of pregnancies in each analysis varied depending on the available data from the outcome being analyzed but ranged from 723 to 4,469,053 pregnancies. When compared with T1D pregnancies, T2D were more likely to have SGA babies as well as greater neonatal and perinatal mortality (OR 2.29, 95% CI 1.12-4.67; OR 1.53 95% CI 1.20-1.94, and OR 1.31 95% CI 1.07-1.61, respectively). When compared with GDM, T2D were more likely to have babies with congenital anomalies (OR 1.91, 95% CI 1.04-3.50), LGA (OR 3.49, 95% CI 2.49-4.89), neonatal mortality (OR 3.96, 95% CI 3.38-4.64), and stillbirth (OR 16.55, 95% CI 5.69-48.11). In comparison to nondiabetic pregnancy, T2D were more likely to have babies with congenital anomalies (OR 1.76, 95% CI 1.11-2.79), LGA (OR 2.79, 95% CI 1.93-4.04), perinatal mortality (OR 4.18, 95% CI 2.91-6.01), and stillbirth (OR 7.27, 95% CI 3.01-17.53).

CONCLUSION

T2D pregnancies are associated with a greater perinatal mortality than other forms of diabetes in pregnancy. Given its increasing prevenance, greater awareness of the adverse pregnancy outcomes associated with T2D is needed, by both healthcare providers and policy makers, to improve care.

Type 1 Diabetes and Pregnancy: Challenges in Glycemic Control and Maternal-Fetal Outcomes

Managing type 1 diabetes during pregnancy presents significant challenges due to physiological and hormonal changes. These factors contribute to major changes in insulin sensitivity, complicating efforts to achieve and sustain optimal blood glucose levels. Poorly controlled glucose levels during pregnancy can result in diabetic embryopathy and elevate the risks of maternal complications such as hypertensive disorders and diabetic ketoacidosis. Fetal complications may include preterm birth, fetal demise, and admission to neonatal intensive care units. It is essential to recognize that there is no universal approach to managing glycemic control in pregnant women with T1DM and care should be individualized. Effective management requires a multidisciplinary approach involving regular monitoring, adjustments in insulin therapy, dietary modifications, and consistent prenatal care. Continuous glucose monitoring has emerged as a valuable tool for real-time glucose monitoring, facilitating tighter glycemic control. Education and support for self-management are important in addressing these challenges. Future developments in technology and personalized approaches to care show promising potential for advancing diabetes management during pregnancy. This provides a comprehensive overview of current literature on the challenges with the management of T1DM during pregnancy, focusing on its impact on maternal and neonatal outcomes and highlighting effective strategies for achieving optimal glycemic control.

Hemoglobin A1c Trajectories During Pregnancy and Adverse Outcomes in Women With Type 2 Diabetes: A Danish National Population-Based Cohort Study

OBJECTIVE

To identify and characterize groups of pregnant women with type 2 diabetes with distinct hemoglobin A1c (HbA1c) trajectories across gestation and to examine the association with adverse obstetric and perinatal outcomes.

RESEARCH DESIGN AND METHODS

This was a retrospective Danish national cohort study including all singleton pregnancies in women with type 2 diabetes, giving birth to a liveborn infant, between 2004 and 2019. HbA1c trajectories were identified using latent class linear mixed-model analysis. Associations with adverse outcomes were examined with logistic regression models.

RESULTS

A total of 1,129 pregnancies were included. Three HbA1c trajectory groups were identified and named according to the glycemic control in early pregnancy (good, 59%; moderate, 32%; and poor, 9%). According to the model, all groups attained an estimated HbA1c <6.5% (48 mmol/mol) during pregnancy, with no differences between groups in the 3rd trimester. Women with poor glycemic control in early pregnancy had lower odds of having an infant with large-for-gestational-age (LGA) birth weight (adjusted odds ratio [aOR] 0.57, 95% CI 0.40-0.83), and higher odds of having an infant with small-for-gestational age (SGA) birth weight (aOR 2.49, 95% CI 2.00-3.10) and congenital malformation (CM) (aOR 4.60 95% CI 3.39-6.26) compared with women with good glycemic control. There was no evidence of a difference in odds of preeclampsia, preterm birth, and caesarean section between groups.

CONCLUSIONS

Women with poor glycemic control in early pregnancy have lower odds of having an infant with LGA birth weight, but higher odds of having an infant with SGA birth weight and CM.