Obstetric Complications and Medical Disorders in Pregnancy
What this domain tests
This domain covers hypertensive disease, diabetes, thyroid and cardiac disease, venous thromboembolism, and the medical disorders that change pregnancy management. Examiners focus on definitions, delivery thresholds, drug safety, and the fact that hypertensive disease remains a leading cause of maternal death in Iran.
Hypertensive disorders
Preeclampsia = new hypertension ≥140/90 after 20 weeks plus proteinuria (≥300 mg/24 h or protein/creatinine ≥0.3) or end-organ features. Severe features: ≥160/110, platelets <100,000, AST/ALT >2× normal, creatinine >1.1 mg/dL, pulmonary edema, or cerebral/visual symptoms. Without severe features, deliver at 37 weeks; with severe features, stabilize and deliver at ≥34 weeks. Magnesium sulfate: 4–6 g IV load over 15–20 minutes, then 1–2 g/h; monitor reflexes, respiratory rate, and urine output; antidote is calcium gluconate 1 g IV. Low-dose aspirin 81–150 mg from 12–16 weeks reduces preeclampsia in high-risk women.
Diabetes and thyroid
Screen with a 75-g OGTT at 24–28 weeks. Targets: fasting <95, 1-hour <140, 2-hour <120 mg/dL. Insulin is first-line; metformin crosses the placenta. Levothyroxine requirements rise 20–30% in pregnancy - recheck TSH every 4 weeks and increase the dose early.
Worked example
At 33 weeks: BP 168/110, 3+ proteinuria, platelets 88,000, AST 120, creatinine 1.3, headache. This is preeclampsia with severe features plus HELLP. Admit, give magnesium sulfate, control BP with labetalol or hydralazine, give corticosteroids, and deliver after stabilization - do not delay delivery for steroid benefit when HELLP and severe hypertension are present.
Traps
Diagnosing preeclampsia before 20 weeks (think molar pregnancy); using methylergonovine postpartum in a hypertensive woman; prescribing ACE inhibitors; missing magnesium toxicity because reflexes are still present.