Abstract Body

Clinicians are increasingly familiar with using the visual 24 hour glucose profile obtained by CGM to personalise the clinical management of diabetes. However at a population level the temporal profiles are not used to ascertain where clinically relevant differences lie across the 24 hour day and any differences in glucose are often masked by summary statistics. This talk will highlight the importance of examining the full 24 hour temporal glucose profiles and illustrate the relevance of this to understanding pregnancy outcomes in women with diabetes.

Abstract Body

During 2019-20, there were 5,085 pregnancies in women with T2D and 4,175 in those with T1D, making T2D now the commonest form of pregestational diabetes in pregnancy in England and Wales. This represents a doubling in the prevalence of T2D pregnancies in the past two decades.

Compared to pregnant women with T1D, those with T2D are older, have higher BMI, with more metabolic comorbidities (hypertension, dyslipidemia) and are more likely to belong to minority ethnic groups, and live in higher deprivation areas. There were seven times more pregnancies (>40% vs <6%) among women with T2D living in the most vs least deprived communities. Fewer than one in four were taking high dose folic acid before pregnancy. Glycaemic management was also inadequate with 25% of women untreated, 50% taking metformin alone, and only 15% taking insulin (10 % metformin and insulin, 5% insulin alone) before pregnancy. Approximately one in seven pregnant women (median age 34 years) were taking ACE-inhibitors, statins (13%) or other potentially harmful therapies (7%).

Pregnant women with T2D had higher rates of perinatal death across all HbA1c categories compared to pregnant women with T1D. After adjusting for relevant confounding risk factors, an above target HbA1c after 24 weeks was associated with a four-times increased risk of perinatal death in T2D. Rates of preterm births, LGA and neonatal intensive care unit admissions are all significantly reduced in women with T2D who achieve HbA1c < 6.1% (43mmol/mol) after 24 weeks gestation (Figure 1), emphasizing the crucial importance of antenatal glucose levels during T2D pregnancy.