A 23-year-old woman with Type 1 diabetes at 20 weeks presents with vomiting and deep sighing respirations. Plasma glucose is 230 mg/dL, pH 7.14, bicarbonate 9 mmol/L, and urine ketones are strongly positive. Compared with non-pregnant patients, diabetic ketoacidosis in pregnancy characteristically develops:
- A Only when glucose exceeds 500 mg/dL
- B With a preserved acid base balance due to progesterone
- C At lower plasma glucose levels, sometimes below 200 mg/dL ✓
- D Without ketonaemia because of placental insulin degradation
Correct answer: C. At lower plasma glucose levels, sometimes below 200 mg/dL
Explanation
Pregnancy is a state of accelerated starvation: human placental lactogen and other anti-insulin hormones, together with continuous fetal and placental glucose consumption and buffering, allow ketoacidosis to develop at glucose values as low as 150 to 200 mg/dL. Recognising this euglycaemic range matters because clinicians who dismiss DKA when glucose is under 250 mg/dL delay insulin and fluid therapy. Acidosis is typically more severe and develops faster than outside pregnancy.
Reference: Williams Obstetrics, 26th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.