Diabetic ketoacidosis in pregnancy poses mortality risk

April 25, 2023

Diabetic ketoacidosis (DKA) in pregnancy is an obstetrical emergency associated with an increased maternal and fetal mortality risk if not promptly identified and treated. DKA complicates 5% to 10% of all pregnancies with pre-gestational and gestational diabetes, and while maternal mortality is rare, fetal mortality rate is estimated to be between 10% and 35%.

Pregnancy is characterized by progressive insulin resistance, particularly throughout the second and third trimesters. The altered metabolic milieu during pregnancy means that DKA can develop more rapidly and at lower plasma glucose concentrations than observed outside of pregnancy, known as euglycemic DKA.

Maheswaran (Mahesh) Dhanasekaran, M.B.B.S., an endocrinology fellow at Mayo Clinic in Rochester, Minnesota, notes: "In a retrospective, multidisciplinary Mayo Clinic study reviewing inpatient events in pregnancies over a 20-year time span, 58 pregnant women with 71 DKA episodes were identified. Most women (86%) had preexisting type 1 diabetes mellitus, with the rest having type 2 diabetes." This study was published in a 2022 edition of The Journal of Clinical Endocrinology & Metabolism.

Notably, several maternal factors were highlighted by this study:

  • Mean maternal age was 28 years, and mean diabetes duration was 11 years.
  • Women who developed DKA had a mean first trimester HbA1c of 9.3%.
  • Social stressors were present in 52% of women, and 24% of women were actively smoking during pregnancy.
  • Preexisting hyperemesis was associated with increased fetal demise (31% versus 3% among live births).

Aoife M. Egan, M.B., B.Ch., Ph.D., an endocrinologist at Mayo Clinic in Rochester, Minnesota, says: "The mean gestational age at DKA was 25.4 weeks (16.3 weeks for pregnancies with fetal demise versus 27.5 weeks for live births). Pregnancy loss during or within one week of the DKA episode occurred in 17% (six miscarriages and four stillbirths). This is comparable to the existing literature, which speaks to poor tolerance of the developing fetus to maternal acidosis."

Dr. Dhanasekaran explains: "The most common precipitating factor for developing DKA was insulin nonadherence (40%), followed by infection (23%) and a new diagnosis of type 1 diabetes (10%) during pregnancy. In total, 39% of women required intensive care unit (ICU) admission, and 41% required an emergency cesarean section. Fortunately, there were no maternal deaths.

"There were no noticeable differences between the biochemical parameters of DKA events that resulted in live birth and fetal demise. However, 21.1% of included episodes could be characterized as euglycemic DKA. Cases were defined as euglycemic DKA if the maximum recorded venous glucose concentration was less than 13.9 mmol/L (250 mg/dL). Neonatal outcomes included large for gestational age in 29% and shoulder dystocia in 8%. A congenital anomaly was present in 10% of neonates. Additionally, neonatal hypoglycemia occurred in 60%, and more than half required neonatal ICU admission."

Dr. Egan concludes: "The results of this study highlight that maternal and neonatal morbidity and high rates of pregnancy loss remain a significant problem. Women presenting with DKA had suboptimally controlled diabetes, before and during pregnancy, and were from lower socioeconomic groups. At-risk pregnant women should be effectively counseled on the risks and adverse consequences of DKA, with education and support ideally commencing pre-pregnancy. Furthermore, timely recognition and management of DKA in pregnancy are crucial for optimizing outcomes. Future work should focus on optimizing prevention strategies in high-risk women."

For more information

Dhanasekaran M, et al. Diabetic ketoacidosis in pregnancy: Clinical risk factors, presentation, and outcomes. The Journal of Clinical Endocrinology & Metabolism. 2022;107:3137.

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