Obstetrics and Gynaecology: Safety-First Clinical Reasoning
Core concepts to master
OB/GYN questions centre on maternal safety and fetal wellbeing. Key areas: hypertensive disorders of pregnancy (pre-eclampsia, eclampsia, HELLP), obstetric haemorrhage (antepartum and postpartum), ectopic pregnancy, labour and fetal monitoring, and gynaecological emergencies such as ovarian torsion and pelvic inflammatory disease. You must also know contraception, menopause management, and cervical screening principles at a practical level.
Common traps
Pre-eclampsia severity is defined by features such as severe hypertension, symptoms, renal or hepatic dysfunction, or fetal compromise - not by the presence of proteinuria alone. In eclampsia, magnesium sulfate is the drug for seizure control and prophylaxis, with blood pressure control alongside; the trap is choosing a different anticonvulsant. In postpartum haemorrhage, the sequence is resuscitation, uterine massage, uterotonics, then escalation; tranexamic acid has an established role. Ectopic pregnancy must be considered in any woman of reproductive age with abdominal pain, even with a negative pregnancy test if the history is suggestive - always confirm with a sensitive beta-hCG. Avoid the pitfall of attributing abdominal pain in pregnancy to pregnancy alone.
Worked rule of thumb
A 32-week pregnant woman has a blood pressure of 165/110, headache, and visual disturbance. This is severe pre-eclampsia. Action: admit, control blood pressure, give magnesium sulfate for seizure prophylaxis, and arrange urgent obstetric review with fetal assessment. The rule of thumb: severe hypertension plus symptoms equals magnesium, regardless of proteinuria.