A Study of Diabetic Ketoacidosis in the Pregnant Population in the United Kingdom. Investigating the incidence, aetiology, management and outcomes.

AIM: To estimate the incidence of diabetic ketoacidosis (DKA) among pregnant women, describe its clinical features, management and outcomes and identify the risk factors for the condition. METHODS: A national population-based case-control study was conducted in the UK using the UK Obstetric Surveillance System between April 2019 and September 2020 including all pregnant women with DKA irrespective of the level of blood glucose. The incidence rate of DKA in pregnancy was estimated. A case-control analysis limited to women with type 1 diabetes was performed comparing characteristics of women with DKA (cases) to those of women whose pregnancies were not complicated by DKA (controls). RESULTS: Eighty-two women were identified with DKA in pregnancy; 6.3 per 100,000 maternities (95% CI 5.0-7.9). No maternal deaths occurred, but perinatal mortality was 12/73 (16%) with eleven stillbirths and one neonatal death. DKA episodes mostly occurred in women with type 1 diabetes (85%) and in the 3rd trimester of pregnancy (71%). Episodes were mainly precipitated by infection (21%), vomiting (21%), steroid therapy (13%) and medication errors (10%). Fifteen percent of women had more than one episode of DKA during their pregnancy. Risk factors associated with DKA among women with type 1 diabetes identified through the case-control analysis were the woman and/or partner not being in a paid employment and having at least one microvascular complication of diabetes before pregnancy. CONCLUSION: DKA in pregnancy was associated with high perinatal mortality and was linked with factors related to socio-economic deprivation, mental health problems and long-term difficulties with glycaemic control.