—multifactorial involving immunologic, genetic and maternal factors that lead to uteroplacental mismatch and endothelial cell dysfunction

—headaches/visual symptoms, chest pain/dyspnea, oxygen saturation <97%, nausea, vomiting, elevated liver enzymes or creatinine, thrombocytopenia, hyperuricemia, oligohydramnios, IUGR, abnormal uterine artery or umbilical cord Doppler flow. SBP ≥160 mmHg most important predictor of fatal stroke among women with hypertensive disorders in pregnancy

—generalized tonic-clonic seizures (eclampsia), PRES (posterior reversible leukoencephalopathy syndrome), cortical blindness/retinal detachment, altered level of consciousness, stroke, pulmonary edema, acute kidney injury, hepatic dysfunction/hematoma/rupture, hemolysis, placental abruption, fetal demise. HELLP (Hemolysis, Elevated Liver Enzymes, Low Platelets) syndrome = constellation of findings considered variant of severe preeclampsia

—extremes of age (<18, >40), nulliparity, multiple gestations, prior preeclampsia, obesity, chronic hypertension, diabetes mellitus, chronic kidney disease, antiphospholipid antibodies, and inter-pregnancy interval ≥10 years

—hemorrhagic stroke from uncontrolled hypertension and eclampsia

—inquire about headaches, visual disturbances, epigastric or RUQ pain, nausea, vomiting, swelling, decreased fetal movements

—check vitals, look for retinal vasospasm, heart failure, edema (facial, limbs), RUQ tenderness, hyperreflexia and clonus

—ABC, O₂ to keep sat >95%, IV with judicious fluid

(SBP ≥160 mmHg or DBP ≥110 mmHg)—labetalol (start with 20 mg IV, repeat 20–80 mg IV q10–30 min, or infusion 1–2 mg/min, max 300 mg), nifedipine short-acting capsule 5–10 mg PO q30min, or hydralazine (start with 5 mg IV, repeat 5–10 mg IV q20–30 min, max 20 mg). Severe cases may require continuous infusion. Consider urgent delivery if not controlled

(SBP 140–159 mmHg or DBP 90–109 mmHg)—target BP at 130–140/80–90 mmHg if renal disease, diabetes, cardiovascular disease, or cerebrovascular disease. Otherwise target BP 130–155/80–105 mmHg; tighter control (DBP 85 mmHg [vs. 100 mmHg]) results in less severe hypertension without significant ↑ risk of adverse fetal outcomes. Labetalol 100–400 mg PO BID–TID, max 1200 mg/day, nifedipine XL 20–60 mg PO daily, max 120 mg/day, or methyldopa 250–500 mg PO BID–TID, max 3 g/day are good first-line choices. Avoid ACE inhibitors, ARBs, atenolol and prazosin. Second-line: other β-blockers and hydralazine. Third line: other CCBs, clonidine, and thiazide diuretics

—MgSO ₄ 4 g IV bolus, then 1–2 g/h × 24–48 h. Re-bolus for ongoing seizures. Monitor for magnesium toxicity (respiratory depression, hypotension, muscle weakness, hyporeflexia) and give calcium gluconate if toxic. MgSO₄ is contraindicated in myasthenia gravis (may precipitate myasthenic crisis). Benzodiazepines, phenytoin and phenobarbital can be considered as adjunctive therapy if ongoing seizures despite MgSO₄

—the cure for preeclampsia, eclampsia, and HELLP. Administer steroids to promote fetal lung maturation prior to 34 weeks if early delivery

—history of hypertensive disorders in pregnancy increases risk for chronic hypertension, cardiovascular events, cerebrovascular accidents, renal disease, type 2 diabetes, and hypothyroidism. Lifestyle changes and routine vascular risk factor screening essential. Women with history of preeclampsia may experience post-traumatic stress disorder; monitor and provide mental health support

—similar to non-pregnant patients. β-agonists, anticholinergics, and glucocorticoids (inhaled, systemic) are safe. Leukotriene antagonists if refractory. Keep O₂ sat >95% to prevent fetal hypoxia. Consider stress dose steroids during delivery if patient required moderate systemic steroids for >3 weeks in the preceding year

—increased risk of DVT/PE due to ↑ factors I, VII, VIII, IX, X, von-Willebrand factor, and fibrin, ↓ protein S and fibrinolytic activity, and increased resistance to activated protein C, especially during T3. Also stasis due to ↓ venous tone and flow. Similar risk of DVT/PE in each trimester but highest post-partum; 90% of DVT in pregnancies are left sided and majority are pelvic

—if suspect venous thromboembolism, consider initiation of LMWH while waiting for investigations. For DVT workup, perform compression US; if pelvic vein DVT suspected, consider MRV pelvis, Doppler study, or (postpartum) CT of pelvic veins. Otherwise, repeat compression US in 5–7 days if still symptomatic. For PE workup, perform V/Q scan if CXR normal (note: if Q normal, can skip V portion of scan). If CXR abnormal and/or V/Q scan non-diagnostic, proceed with CT chest. CT chest is associated with lower fetal radiation exposure than V/Q scan in T₁–T₂, but higher risk of maternal breast cancer (14% increased lifetime risk)

—fetal exposure of <5 cGy [5 rad] accumulatively in each pregnancy is acceptable, but oncologic effects controversial (e.g., childhood leukemia). Consider proximity of fetus to radiations site (i.e., radiation from CT chest > V/Q scan in T₃) and limit where possible (i.e., abdominal shields)

—LMWH dosed using current weight (not pre-pregnancy or ideal body weight). Consider monitoring of anti-Xa level (4–6 h after last dose, target 0.6–1.2 IU/mL). Duration of therapeutic anticoagulation 3–6 months, then transition to prophylactic dose of LMWH until end of 6 weeks postpartum. If neuraxial analgesia, hold therapeutic LMWH × 24 h and prophylactic LMWH × 12 h beforehand. If unable to hold anticoagulation (e.g., acute clot <4 weeks), consider bridging with IV unfractionated heparin (and hold when in active labor or 2 h prior to cesarean section), and/or consider IVC filter. Systemic thrombolysis generally contraindicated (risk of fetal demise). Warfarin not recommended during pregnancy (teratogenic in T₁; associated with fetal CNS hemorrhage/malformations, miscarriage, stillbirth, neonatal demise). May consider warfarin as an alternative to LMWH in the postpartum period while breastfeeding