Gestational Hypertension
Updated On: July 23, 2026
Anesthesia Implications
Confirm it isn't preeclampsia - Urine protein/creatinine ratio ≥0.3 or 24-hour protein ≥300 mg, CBC for platelets, LFTs, and creatinine. New proteinuria or end-organ dysfunction reclassifies her and changes the whole plan.
Severe-feature symptoms - Unremitting headache, altered mental status, scotomata, photophobia, blurred vision or visual field loss, dyspnea or rales, right upper quadrant pain. Symptoms usually appear only above 160/110 and signal end-organ damage.
Treatment thresholds - Antihypertensives are indicated for sustained severe-range pressures (>160/110). ACOG does not recommend treating mild-range pressures unless she was on medication for chronic hypertension before pregnancy. Target 140–150/90–100 mmHg.
Safe agents - Labetalol, hydralazine, and nifedipine are first line; nifedipine or oral labetalol are preferred outpatient. Thiazides can continue if she was on them for chronic hypertension pre-pregnancy.
Agents to avoid - ACE inhibitors, ARBs, mineralocorticoid receptor antagonists, and nitroprusside are teratogenic and contraindicated. Nitroprusside only as a last resort in treatment-resistant hypertension.
Magnesium is for severe features - Seizure prophylaxis is indicated when preeclampsia has severe features and runs until after delivery. Typical dosing is 4–6 g IV load then 1–2 g/hr, targeting serum 2.0–3.5 mEq/L.
Platelets decide neuraxial - Get a CBC. Thrombocytopenia in a hypertensive parturient is what pushes a cesarean toward general anesthesia, and that is where the risk lives.
Airway edema - Preeclamptic airway edema can worsen a Mallampati score within days. Re-examine on the day of surgery rather than trusting a clinic note.
Protect uteroplacental flow - Reduced uterine and umbilical blood flow is the fetal concern, and it is tracked with fetal non-stress testing and amniotic fluid index. Avoid precipitous drops in pressure when you treat.
Delivery is the definitive treatment - Maternal sequelae of gestational hypertension, preeclampsia, and eclampsia resolve rapidly after delivery. Timing balances fetal maturity against maternal risk, and delivery can be indicated as early as 34+0 weeks depending on the diagnosis.
Don't stand down after delivery - Eclamptic seizures run from intrapartum through 72 hours postpartum. Eclampsia occurs in 2–3% of women with severe features who are not on seizure prophylaxis.
Pathophysiology
New hypertension after 20 weeks of gestation in a woman who was normotensive before — systolic ≥140 or diastolic ≥90 mmHg on two occasions at least four hours apart, or a severe-range pressure (≥160/110) confirmed after a short interval so treatment is not delayed. What separates it from preeclampsia is the absence of proteinuria and end-organ dysfunction.
The mechanism is placental. Abnormal trophoblast differentiation and poor remodeling of the deep myometrial spiral arteries produce placental hypoperfusion and ischemia; the ischemic placenta releases antiangiogenic factors that cause systemic endothelial dysfunction. Organ hypoperfusion shows up in the eyes, lungs, liver, kidneys, and peripheral vasculature. Hypertensive disorders complicate 5–10% of pregnancies, and gestational hypertension is a moving diagnosis — it can progress to preeclampsia and eclampsia. Delivery is the cure; it should resolve within 12 weeks postpartum, and if it doesn't, she has chronic hypertension.