Medical Complications of Pregnancy
Core concepts
Chronic medical conditions interact with pregnancy physiology. Know diabetes (preconception counseling, target A1c, fetal surveillance, delivery timing), thyroid disease (levothyroxine dose often increases in pregnancy; treat hypothyroidism to avoid fetal harm), cardiac disease (most common acquired is rheumatic; highest risk lesions include pulmonary hypertension and Eisenmenger), epilepsy (avoid valproate; continue appropriate anticonvulsants), and venous thromboembolism (pregnancy is prothrombotic; low-molecular-weight heparin is preferred). Also understand asthma (continue controller therapy), chronic hypertension, and renal disease. Preconception optimization is a recurring theme.
Traps
Questions often test stopping necessary medications in pregnancy - most chronic disease medications should be continued with adjustment, not abruptly discontinued. Another trap is using warfarin in pregnancy (teratogenic; avoid in first trimester and near delivery). Also, thyroid dosing often requires an increase, not a decrease.
Rule of thumb
For chronic disease in pregnancy, ask: Is the disease controlled? Is the medication the safest option? What is the surveillance and delivery plan? Control usually outweighs theoretical medication risk.