Pregnancy, Childbirth & Puerperium

Chronic hypertension in pregnancy

Clinical Overview and When to Suspect Chronic Hypertension in Pregnancy

— Pre-existing before pregnancy, OR

— Documented before 20 weeks' gestation, OR

— Persisting >12 weeks postpartum

— Known hypertensive woman entering pregnancy (most common scenario)

— BP ≥140/90 at first prenatal visit <20 weeks

— History of HTN in prior pregnancy that never resolved

— Persistent BP elevation in early gestation despite expected physiologic drop (BP normally falls in T1–T2 by 5–10 mmHg)

— Mild–moderate: 140–159/90–109

— Severe: ≥160/110

— Primary (essential) HTN: ~90%

— Secondary HTN: renal artery stenosis, primary aldosteronism, pheochromocytoma, renal parenchymal disease, coarctation, thyroid disease — screen if onset <30 yo, refractory, hypokalemia, or end-organ damage

Definition: Chronic hypertension (cHTN) in pregnancy = BP ≥140/90 mmHg on two occasions ≥4 hours apart, either:

Epidemiology: Affects ~2–5% of pregnancies; rising with delayed childbearing, obesity, and metabolic syndrome

Why it matters: cHTN doubles risk of superimposed preeclampsia, abruption, fetal growth restriction (FGR), preterm birth, stillbirth, and maternal stroke

When to suspect:

Severity categories (ACOG):

Etiology breakdown:

Risk factors: African ancestry, obesity (BMI ≥30), age ≥35, DM, CKD, prior preeclampsia, family history

Step 3 management: At preconception counseling, switch teratogenic agents (ACEi, ARB, direct renin inhibitors, MRAs) to pregnancy-safe alternatives (labetalol, nifedipine ER, methyldopa) before conception whenever possible.

Board pearl: A BP of 142/92 at 10 weeks in a woman with no prior records still counts as chronic HTN — the <20-week threshold defines it, not pre-pregnancy documentation alone.

Key distinction: cHTN vs gestational HTN = timing (<20 vs ≥20 wks) and persistence postpartum (>12 wks = chronic).

Presentation Patterns and Key History

— 34-yo G2P1 with known HTN on lisinopril presents for preconception visit

— 28-yo at 12 weeks with BP 148/94, BMI 34, family hx HTN

— 39-yo with prior preeclampsia returning for second pregnancy with persistent 145/92 between pregnancies

— Postpartum woman at 8 weeks still hypertensive — too early to call cHTN, recheck at 12 weeks

— Duration and prior control of HTN; baseline BP readings

— All current antihypertensives — specifically ask about ACEi/ARB use (fetopathy: oligohydramnios, renal dysgenesis, skull hypoplasia, limb contractures, especially T2/T3)

— Prior pregnancy complications: preeclampsia, HELLP, IUGR, abruption, preterm delivery, stillbirth

— End-organ symptoms: headache, visual change, chest pain, dyspnea, hematuria

— Secondary HTN clues: episodic palpitations/sweating (pheo), muscle weakness/cramping (hyperaldo), claudication (coarctation), recurrent UTIs/flank pain (renal)

— Lifestyle: sodium intake, alcohol, tobacco, cocaine/stimulant use, OTC NSAIDs, decongestants

— Sleep apnea symptoms (loud snoring, witnessed apnea, daytime somnolence) — common, treatable contributor

— Combined oral contraceptives in the chart pre-conception

— Herbal supplements (licorice → pseudohyperaldosteronism)

— Stimulants for ADHD (amphetamines raise BP)

Typical scenarios on Step 3:

Key history elements:

Comorbidity screen: DM, dyslipidemia, CKD, lupus/APLS, thyroid disease, prior cardiac disease

Family/social: First-degree HTN, preeclampsia in mother or sisters, occupational stress, intimate partner violence (affects medication adherence and BP)

Medication reconciliation pitfalls:

CCS pearl: On a CCS case, order "obstetric history, complete" plus "medication reconciliation" at first visit; advancing the clock without stopping the ACEi will accrue fetal harm points.

Board pearl: New-onset HTN before 20 weeks + hypokalemia → think primary aldosteronism; order plasma aldosterone:renin ratio before pregnancy when possible.

Physical Exam Findings and Hemodynamic Assessment

— Seated, back supported, feet flat, arm at heart level, after 5 min rest

— Appropriate cuff size (bladder encircling 80% of arm); wrong cuff is the #1 cause of falsely elevated readings in obese gravidas

— Korotkoff phase V (disappearance) for diastolic

— Confirm elevation with repeat ≥4 hours apart for non-severe; severe range (≥160/110) confirmed within 15 minutes triggers acute treatment

— Home BP monitoring or 24-hour ambulatory BP to exclude white-coat HTN (up to 30% of pregnant women)

— Masked HTN (normal office, high home) carries similar risk to sustained HTN

— Fundoscopy: AV nicking, arteriolar narrowing, hemorrhages, exudates, papilledema (end-organ damage)

— Cardiac: LV heave, S4 (LVH), murmurs (coarctation → radio-femoral delay, interscapular bruit)

— Pulmonary: rales (pulmonary edema in severe disease)

— Abdominal: renal bruits (renovascular HTN), masses

— Neurologic: focal deficits, hyperreflexia, clonus (especially if superimposed preeclampsia suspected)

— Extremities: edema (nonspecific in pregnancy), pulses (coarctation)

— Skin: café-au-lait (NF1 → pheo, renal artery stenosis), striae (Cushing)

— Fundal height (FGR if lagging ≥3 cm)

— Fetal heart tones; document at every visit

— Normal pregnancy: ↑CO 30–50%, ↓SVR, ↓BP nadir at 20–24 weeks

— In cHTN, BP may "normalize" mid-pregnancy then rise in T3 — do not stop meds based on transient normalization without close monitoring

BP measurement technique (testable):

Out-of-office confirmation:

Targeted exam:

Obstetric exam:

Hemodynamic patterns:

Key distinction: Hyperreflexia + clonus + RUQ tenderness + new proteinuria in a cHTN patient at 28 weeks = superimposed preeclampsia, not worsening cHTN — management diverges sharply.

Board pearl: Radio-femoral delay in a young hypertensive pregnant patient = coarctation until proven otherwise; obtain echo.

Diagnostic Workup — Initial Labs, Imaging, and Baseline Studies

— CBC (platelets baseline)

— Comprehensive metabolic panel: creatinine, electrolytes, liver enzymes, uric acid

— Urinalysis with microscopy

— Quantitative proteinuria: spot urine protein:creatinine ratio (UPCR) or 24-hour urine protein

· Baseline protein ≥300 mg/24h or UPCR ≥0.3 documents pre-existing proteinuric renal disease — critical because new/worsening proteinuria later = superimposed preeclampsia

— TSH (if not recently checked)

— HbA1c or fasting glucose (HTN + DM common)

— Lipid panel (for postpartum CV risk planning)

— Renal ultrasound if creatinine elevated, hematuria, or asymmetric kidneys suspected

— Avoid CT/contrast unless indicated; MR angiography (without gadolinium) acceptable for renovascular workup if needed

— Dating ultrasound (accurate EDD critical for later growth assessments)

— Early anatomy and viability scan

— cHTN alone is a high-risk factor → start low-dose aspirin 81 mg daily between 12–28 weeks (ideally before 16 wks) and continue until delivery to reduce preeclampsia risk

Purpose: Establish baseline to detect future superimposed preeclampsia and identify end-organ damage or secondary causes

Baseline labs at first prenatal visit (or preconception):

ECG: All women with cHTN at baseline — LVH, prior MI, conduction disease

Echocardiogram: If LVH on ECG, long-standing HTN, symptoms, or planning pregnancy with severe HTN; assesses LV function and excludes coarctation

Imaging caveats:

Obstetric baseline:

Aspirin risk assessment (USPSTF/ACOG):

Step 3 management: At the first prenatal visit for a cHTN patient, simultaneously order: baseline labs (CBC, CMP, UPCR), ECG, dating US, and start ASA 81 mg if ≥12 weeks. Do not delay aspirin awaiting labs.

Board pearl: Baseline UPCR is the single most useful test to distinguish later superimposed preeclampsia from chronic proteinuric kidney disease.

Diagnostic Workup — Secondary HTN Evaluation and Surveillance Studies

— Age <30 with no family history

— Severe or resistant HTN (≥3 agents)

— Abrupt onset or worsening

— Hypokalemia (unprovoked), metabolic alkalosis

— Episodic symptoms (headache, palpitations, diaphoresis) → pheochromocytoma

— Elevated creatinine, abnormal urine sediment → renal parenchymal disease

— Abdominal bruit, flash pulmonary edema → renovascular

— Primary aldosteronism: plasma aldosterone:renin ratio — note pregnancy markedly raises renin and aldosterone, so interpretation is unreliable after conception; defer to postpartum when possible

— Pheochromocytoma: plasma free metanephrines or 24-hour urine metanephrines — safe in pregnancy and must not be missed (maternal mortality up to 50% if unrecognized at delivery)

— Cushing: late-night salivary cortisol or 24-hour urine free cortisol (dexamethasone suppression less reliable in pregnancy)

— Renovascular: renal Doppler US first-line in pregnancy; MRA without gadolinium if needed

— Coarctation: TTE

— Thyroid: TSH, free T4

— BP at every visit; increase frequency in T3

— Weekly–biweekly CBC, CMP, UPCR starting around 24–28 weeks or sooner if BP worsens

— Fetal growth ultrasound every 4 weeks starting 28 weeks (FGR risk)

— Antenatal testing (NST or BPP) starting 32–34 weeks weekly, twice weekly if FGR or worsening HTN

When to evaluate for secondary HTN:

Targeted secondary workup (ideally preconception):

Ongoing surveillance for superimposed preeclampsia:

Sleep study: Low threshold for polysomnography in obese gravidas with resistant HTN

Board pearl: A pregnant patient with paroxysmal hypertension, headache, and diaphoresis needs plasma free metanephrines now — alpha-blockade (phenoxybenzamine) before beta-blockade, and cesarean with adrenalectomy planning if confirmed.

Key distinction: Worsening proteinuria alone in cHTN ≠ superimposed preeclampsia; requires severe features or new HTN escalation per ACOG 2020 criteria.

Risk Stratification and First-Line Management Logic

— Treat to BP <140/90 in all pregnant women with cHTN (mild or severe)

— CHAP showed treating mild cHTN to <140/90 reduced composite of severe preeclampsia, preterm birth <35 wks, abruption, and fetal/neonatal death without increasing SGA

— Prior threshold of 150/100 is outdated

— Low-risk cHTN: well-controlled on monotherapy, no end-organ damage, no prior preeclampsia → standard prenatal care + aspirin + monthly growth scans starting 28 wks

— High-risk cHTN: severe HTN, multi-agent therapy, end-organ damage (LVH, CKD, retinopathy), prior preeclampsia/abruption/FGR, secondary HTN, DM, age ≥40 → MFM co-management, intensified surveillance

— Switch teratogens (ACEi, ARB, aliskiren, MRA, atenolol) to labetalol or nifedipine ER

— Achieve BP <140/90 before conception

— Optimize weight, glycemic control, smoking cessation

— Folic acid 0.4–1 mg daily

— Confirm dating

— Baseline labs and ECG

— Aspirin 81 mg starting at 12 weeks

— Continue or initiate first-line agent

— Modest sodium reduction (do not institute strict low-sodium diets during pregnancy — may worsen volume status)

— Regular moderate exercise

— Weight gain per IOM guidelines based on pre-pregnancy BMI

— Avoid alcohol, tobacco

Goal of treatment (CHAP trial 2022, now ACOG-endorsed):

Risk stratification framework:

Preconception optimization (ideal):

First trimester management:

Lifestyle:

Step 3 management: For a newly identified gravida at 14 weeks with BP 146/94, the correct moves are: start labetalol 200 mg BID (or nifedipine ER 30 mg daily), start ASA 81 mg, order baseline labs/UPCR, schedule MFM consult, and arrange BP recheck in 1–2 weeks — not "lifestyle modification alone."

Board pearl: Post-CHAP, withholding antihypertensives in mild cHTN is no longer standard — it's a wrong answer.

Pharmacotherapy — First-Line Drug Regimen

— Labetalol (combined α/β-blocker)

· Start 100–200 mg PO BID; max 2400 mg/day divided

· Avoid in asthma, decompensated HF, bradycardia, heart block

· Most commonly chosen first-line in US practice

— Nifedipine extended-release (DHP CCB)

· Start 30 mg PO daily; max 120 mg/day

· Useful when β-blockade contraindicated; good for women with Raynaud or migraines

· Avoid short-acting nifedipine for chronic management

— Methyldopa (central α2-agonist)

· 250 mg PO BID–QID; max 3 g/day

· Long safety record but less effective, sedation, depression, rare hepatitis and Coombs-positive hemolytic anemia

· Now considered second-line; reasonable if labetalol and nifedipine not tolerated

— Hydralazine (oral) — usually adjunct, not monotherapy due to reflex tachycardia

— Thiazides — can continue if pre-pregnancy use and well-tolerated; theoretical volume contraction concern, but data reassuring

— Clonidine — limited data, reserved cases

— ACE inhibitors and ARBs (all trimesters; worst in T2/T3) — fetal renal dysgenesis, oligohydramnios, pulmonary hypoplasia, skull defects, IUGR, neonatal hypotension and death

— Direct renin inhibitors (aliskiren)

— Mineralocorticoid receptor antagonists (spironolactone — antiandrogen effects; eplerenone limited data)

— Atenolol — associated with FGR

— Nitroprusside — cyanide toxicity if prolonged

— IV labetalol 20 mg, then 40, 80, 80, 80 mg q10 min (max 300 mg)

— IV hydralazine 5–10 mg q20 min

— PO immediate-release nifedipine 10 mg q20 min

First-line agents in pregnancy:

Acceptable add-ons / second-line:

Absolutely contraindicated:

Severe acute HTN (≥160/110) in pregnancy/postpartum — treat within 30–60 minutes:

CCS pearl: For a gravida admitted with BP 168/112, order IV labetalol 20 mg now, recheck BP in 10 min, advance dose per protocol; simultaneously order CBC, CMP, LDH, UPCR, and continuous fetal monitoring.

Board pearl: Discovering a pregnant patient on lisinopril → stop immediately, switch to labetalol or nifedipine, document counseling on fetopathy, and obtain detailed anatomy scan + amniotic fluid assessment.

Expanded Pharmacology — Combination Therapy and Resistant Hypertension

— Step 1: Monotherapy (labetalol or nifedipine ER) titrated to max tolerated

— Step 2: Add second agent from different class (labetalol + nifedipine ER is the most common combo)

— Step 3: Add methyldopa or hydralazine

— Step 4: Reassess for secondary HTN, adherence, sleep apnea, white-coat effect; involve MFM and obstetric anesthesia

— Labetalol crosses placenta; neonatal bradycardia/hypoglycemia possible — alert pediatrics at delivery

— Nifedipine + magnesium sulfate: theoretical neuromuscular blockade risk, but co-administration is acceptable; monitor for hypotension and weakness, do not withhold magnesium for seizure prophylaxis

— Methyldopa: avoid in active liver disease, depression history; obtain LFTs and Coombs at baseline

— Hydralazine: drug-induced lupus with prolonged use; reflex tachycardia — pair with β-blocker if tachycardia limits use

— Reassess adherence, white-coat, secondary causes

— Sleep apnea evaluation

— Renal Doppler if not yet done

— Severe-range BP persisting ≥15 minutes is an emergency requiring acute IV therapy and labor and delivery admission

— Add magnesium sulfate 4–6 g IV load then 1–2 g/hr if features of preeclampsia with severe features or eclampsia prophylaxis indicated

— Compatible: labetalol, nifedipine, methyldopa, enalapril, captopril, propranolol, hydrochlorothiazide (low dose)

— Avoid: atenolol (concentrated in breast milk), high-dose diuretics (may suppress lactation)

Stepwise escalation:

Drug-specific pearls:

Resistant HTN definition: BP above goal on 3 agents including a diuretic at optimal doses, or controlled requiring ≥4 agents

Hypertensive emergency in pregnancy:

Breastfeeding compatibility (important transition-of-care issue):

Step 3 management: Postpartum, resume or initiate ACEi (enalapril/captopril) for women who will breastfeed and need ongoing therapy — both are lactation-compatible and offer renal protection, especially in DM/CKD.

Board pearl: Methyldopa + new fatigue and jaundice in a gravida → check LFTs and direct Coombs; drug-induced hepatitis or hemolysis requires switch.

Special Populations — Renal and Hepatic Impairment

— Pregnancy is high-risk if baseline Cr >1.4 mg/dL, proteinuria >1 g/day, or HTN

— Risk of accelerated GFR decline, superimposed preeclampsia (up to 40–60%), preterm birth, FGR

— Stricter BP target: <140/90, with many MFMs targeting 120–135/80–85 if tolerated; avoid hypotension that compromises placental perfusion

— Continue aspirin 81 mg

— Nephrology + MFM co-management

— Avoid ACEi/ARB antepartum despite renal benefit; resume postpartum, especially if proteinuric

— Wait ≥1 year post-transplant, stable graft function, BP controlled, no recent rejection

— Switch mycophenolate (teratogen) preconception to azathioprine or tacrolimus

— Labetalol or nifedipine for HTN

— Methyldopa contraindicated in active liver disease

— Labetalol hepatically metabolized — monitor LFTs if symptoms; rare hepatocellular injury

— Avoid labetalol if baseline transaminitis without workup

— Nifedipine: hepatic metabolism; lower starting dose if cirrhosis

— Hydralazine: dose reduction in severe renal impairment

— Atenolol (avoided anyway) requires renal dose adjustment

— Intensified dialysis (≥36 hrs/week) improves outcomes

— BP control between sessions challenging; nifedipine ER often used

— Aspirin recommended

— Baseline proteinuria in CKD means UPCR has limited utility for diagnosing superimposed preeclampsia — rely on BP trajectory, platelet count, LFTs, and clinical features

— Uric acid less useful in CKD

CKD in pregnancy with cHTN:

Renal transplant recipients:

Hepatic impairment:

Dosing adjustments:

Dialysis in pregnancy:

Special lab considerations:

Step 3 management: In a pregnant woman with diabetic nephropathy (Cr 1.6, UPCR 1.2), discontinue ACEi at conception (or ideally preconception), start labetalol, continue aspirin 81 mg, co-manage with nephrology and MFM, plan delivery by 37–38 weeks, and restart ACEi postpartum for renal protection.

Key distinction: In CKD with baseline proteinuria, the diagnosis of superimposed preeclampsia hinges on new BP escalation or severe features (thrombocytopenia, elevated transaminases, renal worsening beyond baseline, neurologic symptoms, pulmonary edema) — not proteinuria changes alone.

Special Populations — Adolescents, Advanced Maternal Age, and Postpartum

— Rare but rising with obesity; always evaluate for secondary causes (renal, coarctation)

— Adherence challenges; once-daily nifedipine ER often preferred

— Confidentiality and consent: in most US states, pregnant minors can consent to their own prenatal care

— Higher baseline cHTN prevalence

— Increased risk of superimposed preeclampsia, gestational DM, FGR, stillbirth

— Lower threshold for antenatal testing starting 32 weeks

— Discuss aneuploidy screening per standard protocols

— Use appropriately sized BP cuff; consider conical or thigh cuff if upper arm circumference >32 cm

— Higher aspirin dose discussed (some advocate 162 mg in very high-risk) but standard is 81 mg

— Screen for OSA

— Doubles preeclampsia risk; intensified surveillance

— Aspirin indicated

— BP often rises 3–6 days postpartum due to fluid mobilization

— 40% of eclampsia and a large share of maternal strokes occur postpartum, often after discharge

— Continue or initiate antihypertensives; avoid NSAIDs in women with severe-range BP or AKI (ACOG: NSAIDs acceptable in most cHTN patients with adequate BP control, but hold if BP poorly controlled or end-organ injury)

— BP check within 3–7 days of discharge; sooner (72 hrs) for severe features

— Telehealth or home BP monitoring programs reduce readmission

— Encourage breastfeeding; labetalol, nifedipine, methyldopa, enalapril, captopril compatible

— Methyldopa increases postpartum depression risk — switch within first weeks postpartum

— Avoid combined estrogen-containing contraceptives (raise BP, VTE risk)

— Preferred: progestin-only pills, LARC (IUD, implant), DMPA

Adolescent pregnancy with cHTN:

Advanced maternal age (≥35, especially ≥40):

Obesity (BMI ≥30):

Multifetal gestation:

Postpartum period — highest-risk window:

Lactation:

Contraception counseling:

Board pearl: Postpartum day 5 with BP 172/108 and headache → IV labetalol or hydralazine, magnesium sulfate, neuroimaging if focal deficits, admit — late postpartum preeclampsia is a leading cause of maternal stroke.

Step 3 management: At hospital discharge, schedule BP check at 72 hours and 7–10 days, prescribe home BP cuff, give explicit return precautions (headache, vision change, RUQ pain, SOB), and confirm postpartum contraception plan.

Complications and Adverse Outcomes

— Superimposed preeclampsia (20–50% of cHTN pregnancies vs 3–5% baseline)

· Defined by new-onset proteinuria, sudden BP worsening, or new severe features in known cHTN

— HELLP syndrome: hemolysis, elevated LFTs, low platelets

— Eclampsia: seizures

— Hypertensive emergency: encephalopathy, stroke (hemorrhagic > ischemic), pulmonary edema, MI, aortic dissection

— Placental abruption (2–3× baseline)

— Postpartum hemorrhage (uterine atony risk)

— Acute kidney injury

— Cardiomyopathy including peripartum CM

— Fetal growth restriction (FGR) (10–20%)

— Preterm birth (iatrogenic and spontaneous)

— Stillbirth (2–4× baseline risk)

— Oligohydramnios

— Neonatal effects from medications: bradycardia (labetalol), hypotension (any agent), hypoglycemia

— ACEi/ARB fetopathy: renal dysgenesis, oligohydramnios sequence, skull hypoplasia

— cHTN with superimposed preeclampsia confers ~2× lifetime risk of CV death, stroke, HF

— Earlier-onset HTN and metabolic syndrome

— Need for aggressive postpartum CV risk reduction

— Higher rates of childhood HTN, obesity, neurodevelopmental issues if FGR or preterm

— Severe headache unresponsive to acetaminophen

— Visual scotomata, blurring, photopsia

— RUQ or epigastric pain

— Dyspnea, orthopnea

— Decreased fetal movement

— BP ≥160/110

Maternal complications:

Fetal/neonatal complications:

Long-term maternal CV risk:

Long-term offspring effects:

Warning signs that mandate urgent evaluation:

CCS pearl: For a gravida at 32 weeks with BP 165/105, headache, and platelets 88k → admit to L&D, IV labetalol, magnesium sulfate, betamethasone for fetal lung maturity, CBC/CMP/LDH/UPCR, continuous fetal monitoring, MFM consult, plan delivery timing based on stability — this is severe-features preeclampsia superimposed on cHTN.

Board pearl: New thrombocytopenia + AST/ALT elevation in a cHTN gravida = HELLP; delivery is the definitive treatment regardless of gestational age once stabilized.

When to Escalate Care — ICU, Consult, and Inpatient Triage

— Well-controlled BP <140/90 on stable regimen

— No severe features

— Reassuring fetal growth and testing

— Reliable patient with home BP monitoring and access to care

— Severe-range BP not controlled with oral therapy within hours

— Superimposed preeclampsia with severe features

— Eclampsia

— Suspected HELLP

— Pulmonary edema

— New end-organ dysfunction (AKI, transaminitis, thrombocytopenia)

— Non-reassuring fetal status (FGR with abnormal Dopplers, oligohydramnios, abnormal NST/BPP)

— Abruption

— Stroke symptoms

— Hypertensive encephalopathy

— Stroke, intracranial hemorrhage

— Pulmonary edema requiring NIV/intubation

— Refractory severe HTN requiring IV infusion (nicardipine, labetalol drip)

— Hemodynamic instability, MI, dissection

— Eclampsia with prolonged altered mental status

— DIC, severe HELLP requiring transfusion

— MFM: all cHTN pregnancies ideally, mandatory if severe, secondary HTN, prior adverse outcomes, multiple agents

— Nephrology: CKD, proteinuria >1 g, transplant

— Cardiology: LV dysfunction, arrhythmia, coarctation, suspected pheo

— Endocrinology: suspected secondary endocrine cause

— Obstetric anesthesia: severe HTN, BMI ≥40, anticipated complicated delivery — antepartum consult ideal

— Neurology: stroke, seizures atypical for eclampsia

— cHTN without medications: 38 0/7–39 6/7 weeks

— cHTN on medications, well-controlled: 37 0/7–39 0/7 weeks

— cHTN with difficult control: 36 0/7–37 6/7 weeks

— Superimposed preeclampsia without severe features: 37 0/7 weeks

— Superimposed preeclampsia with severe features: 34 0/7 weeks (after steroids if <34)

Outpatient management criteria:

Indications for inpatient admission:

ICU criteria:

Consultations:

Delivery timing (ACOG):

Step 3 management: Escalate to L&D for BP ≥160/110 confirmed within 15 minutes; do not send home for outpatient follow-up. Severe-range BP is treated within 30–60 minutes of confirmation.

CCS pearl: In severe disease, co-order MFM consult, anesthesia consult, NICU notification, and type & screen simultaneously when planning preterm delivery — the clock penalizes sequential ordering.

Key Differentials — Same-Category Hypertensive Disorders

— Chronic hypertension: HTN before 20 weeks or persisting >12 weeks postpartum

— Gestational hypertension: New HTN ≥20 weeks without proteinuria or severe features; resolves <12 weeks postpartum

— Preeclampsia: New HTN ≥20 weeks + proteinuria (UPCR ≥0.3 or 24h ≥300 mg) OR severe features (thrombocytopenia <100k, Cr >1.1, transaminases 2× ULN, pulmonary edema, persistent headache/visual symptoms)

— Preeclampsia with severe features: BP ≥160/110 or any severe feature

— Superimposed preeclampsia: cHTN + new proteinuria, sudden BP rise, or new severe features

— Eclampsia: seizures in setting of preeclampsia

— HELLP syndrome: hemolysis (LDH ≥600, schistocytes), AST/ALT ≥2× ULN, platelets <100k

— White-coat HTN: elevated office BP, normal ambulatory/home BP — still requires monitoring, ~40% develop sustained HTN

— Masked HTN: normal office, elevated home BP — equal risk to sustained HTN

— Timing relative to 20 weeks is the single most useful discriminator between cHTN and gestational HTN/preeclampsia

— Postpartum persistence >12 weeks confirms chronicity

— Proteinuria documented before 20 weeks → either pre-existing renal disease or unrecognized cHTN with nephropathy

— Preeclampsia <20 weeks → think molar pregnancy, antiphospholipid syndrome, severe lupus nephritis, or unrecognized renal disease

— Postpartum new HTN at 4–6 weeks → late postpartum preeclampsia

Hypertensive disorders of pregnancy spectrum:

Differentiation tips:

Atypical presentations:

Key distinction: cHTN + new proteinuria after 20 weeks does not automatically mean superimposed preeclampsia if baseline proteinuria was present and is stable — look for sudden worsening, severe features, or platelets/LFTs/Cr derangement.

Board pearl: HTN + proteinuria + seizure at 16 weeks → suspect molar pregnancy (hCG-driven early preeclampsia); obtain pelvic US.

Step 3 management: When timing is unclear (no BP records before 20 weeks), manage as if chronic if HTN persists postpartum >12 weeks; this guides aspirin in future pregnancies and lifelong CV risk planning.

Key Differentials — Other-Category Causes of Elevated BP

— Renal parenchymal disease: GN, polycystic kidney disease, diabetic nephropathy, reflux nephropathy — check Cr, UA, renal US

— Renovascular: fibromuscular dysplasia (young women, especially in pregnancy), atherosclerotic renal artery stenosis — renal Doppler

— Primary aldosteronism: hypokalemia, metabolic alkalosis; pregnancy-induced renin elevation complicates testing

— Pheochromocytoma: paroxysmal HTN, headache, palpitations, diaphoresis; can be lethal at delivery; always rule out if suggestive

— Cushing syndrome: central obesity, striae, moon face, glucose intolerance

— Hyperthyroidism / hypothyroidism: TSH abnormalities

— Coarctation of aorta: arm-leg BP differential, radio-femoral delay, interscapular bruit, rib notching

— Obstructive sleep apnea: very common, often missed

— Drug-induced: NSAIDs, decongestants, stimulants (amphetamines, cocaine), licorice, oral contraceptives (pre-pregnancy), SSRIs (mild), erythropoietin

— Anxiety/pain: situational; ambulatory monitoring clarifies

— Posterior reversible encephalopathy syndrome (PRES): headache, vision change, seizures; often with eclampsia but can occur with other causes

— Reversible cerebral vasoconstriction syndrome (RCVS): thunderclap headache postpartum

— Cerebral venous thrombosis: postpartum headache with focal deficits or seizures — image with MRV

— Subarachnoid hemorrhage: thunderclap headache — CT then LP if needed

— Thrombotic microangiopathies: TTP, aHUS, catastrophic APS — overlap with HELLP; ADAMTS13, complement workup

— Acute fatty liver of pregnancy: nausea, RUQ pain, hypoglycemia, coagulopathy — distinct from HELLP

Secondary HTN causes to consider:

Mimics of hypertensive emergency in pregnancy:

Key distinction: HELLP vs TTP — TTP typically has more profound thrombocytopenia, normal LFTs, ADAMTS13 <10%, schistocytes prominent, often neurologic; HELLP improves rapidly postpartum, TTP requires plasma exchange.

Board pearl: A pregnant patient with episodic hypertensive crises and a known adrenal mass — alpha-blockade first (phenoxybenzamine), then beta-blockade, then planned cesarean with adrenalectomy (often postpartum); never give beta-blocker alone in pheochromocytoma.

Step 3 management: Persistent hypokalemia in a hypertensive gravida warrants postpartum aldosterone:renin testing — defer definitive workup until lactation complete or non-confounding.

Secondary Prevention, Discharge Medications, and Long-Term Plan

— Continue or resume antihypertensives; target <140/90, often <130/80 long-term per ACC/AHA

— Choose lactation-compatible agents: labetalol, nifedipine ER, enalapril, captopril, methyldopa (limited by depression risk)

— ACEi/ARB are now first-line postpartum especially with DM, CKD, proteinuria, HFrEF

— Avoid NSAIDs in poorly controlled HTN or AKI; otherwise short courses acceptable per ACOG

— Antihypertensive(s) with explicit titration plan

— Home BP cuff (validate technique before discharge)

— Aspirin 81 mg if planning future pregnancy (resume at 12 weeks next pregnancy)

— Contraception plan: progestin-only or LARC; avoid combined estrogen

— Iron, prenatal vitamin continuation as appropriate

— Mental health screening tools and resources

— Women with cHTN + prior preeclampsia have doubled lifetime CV risk

— Lifetime annual BP check, lipid screening every 4–6 years, DM screening

— Lifestyle: DASH diet, sodium <2.3 g/day (long-term, not during pregnancy), aerobic exercise 150 min/week, weight management, smoking cessation, moderate alcohol

— Statin indicated per ASCVD risk calculator (deferred during lactation if possible; not strictly contraindicated)

— Optimize BP and switch off teratogens before conception

— Aspirin 81 mg from 12 weeks

— Preconception counseling about recurrence risk of superimposed preeclampsia (~20–50%)

— Genetic/secondary HTN workup if not yet done

— Postpartum care gap is a leading driver of maternal morbidity; ensure insurance continuity (postpartum Medicaid extension to 12 months in many states)

— Warm handoff to primary care or internal medicine for long-term HTN management

Postpartum BP management:

Discharge prescription checklist:

Cardiovascular risk reduction:

Future pregnancy planning:

Health systems considerations:

Step 3 management: At the postpartum visit, convert labetalol to a lactation-compatible long-term agent (e.g., enalapril if proteinuric/DM, or amlodipine if not), ensure PCP follow-up within 4 weeks, schedule ASCVD risk discussion at 6 months, and document contraception.

Board pearl: Postpartum is a "teachable moment" for lifetime CV health — counseling here changes outcomes decades later.

Follow-Up, Monitoring Parameters, and Counseling

— Every 2–4 weeks until 28 weeks

— Every 1–2 weeks 28–36 weeks

— Weekly after 36 weeks

— More frequent if poor control or superimposed preeclampsia concerns

— BP (proper technique)

— Weight

— Fundal height

— Fetal heart tones / movement

— Symptoms: headache, vision, RUQ pain, edema, dyspnea

— Medication adherence and side effects

— Home BP log review

— CBC, CMP, UPCR every 4 weeks from 24 weeks; more often if concerns

— LDH, uric acid if preeclampsia suspected

— Growth ultrasound every 4 weeks starting 28 weeks

— Umbilical artery Doppler if FGR

— Antenatal testing (NST or BPP) starting 32–34 weeks weekly; twice weekly if high-risk

— Kick counts daily from 28 weeks

— Validated upper-arm cuff

— Twice daily (morning and evening); log readings

— Action thresholds: BP ≥160/110 → call/911; ≥140/90 sustained → call OB

— BP check at 72 hours and 7–10 days post-discharge (ACOG)

— Comprehensive postpartum visit by 6 weeks

— PCP transition by 3 months

— Warning signs and when to seek care

— Medication safety, especially in lactation

— Contraception

— Future pregnancy aspirin and preconception optimization

— Long-term CV risk

— Lifestyle modifications

— Mental health: postpartum depression rates higher with hypertensive disorders

Antepartum visit cadence:

At each visit, document:

Laboratory monitoring:

Fetal surveillance:

Home BP monitoring:

Postpartum follow-up:

Counseling priorities:

Cardiac rehab/structured exercise not specifically indicated unless overt heart disease; encourage moderate aerobic activity 150 min/week long-term

Step 3 management: For postpartum BP 152/96 at the 1-week check, uptitrate current agent or add second agent (do not "watch"), schedule recheck in 1 week, and reinforce home BP logs; failure to act is a common test trap.

Board pearl: A documented postpartum BP plan reduces readmission and is increasingly a quality metric in maternal care bundles.

Ethical, Legal, and Patient Safety Considerations

— Refusal of magnesium sulfate or antihypertensives in severe preeclampsia: document capacity assessment, risks (stroke, death, fetal demise), benefits, alternatives, and offer continued care; involve ethics if persistent refusal

— Refusal of indicated delivery at 34 weeks for severe-features superimposed preeclampsia: respect autonomy but document maternal-fetal risks clearly; multidisciplinary meeting; do not coerce

— Periviable delivery decisions (22–25 weeks): shared decision-making with neonatology; document goals-of-care

— AIM (Alliance for Innovation on Maternal Health) Severe Hypertension in Pregnancy bundle: standardized protocols for recognition, rapid treatment within 30–60 minutes, debriefing, and quality improvement

— Standing orders for IV labetalol/hydralazine on L&D

— Early warning systems (MEWS, MEOWS) trigger response teams

— Postpartum discharge without BP follow-up is a leading driver of readmission for severe HTN and stroke

— Ensure: discharge BP <150/100, written action plan, home cuff, follow-up within 3–7 days, medication reconciliation, breastfeeding-compatible regimen

— Handoff to PCP and pediatrician communication regarding maternal medications and infant monitoring

— Black women have 3–4× higher maternal mortality; severe-features HTN is a leading cause

— Implicit bias contributes to delayed recognition; standardized protocols mitigate disparity

— Address social determinants: insurance, transportation, food access

— Intimate partner violence: offer resources; reporting laws vary by state

— Substance use: state laws vary; some require reporting in pregnancy — counsel on disclosure implications

— Pregnant adolescents can consent to prenatal care in most states; protect confidentiality from parents per state law

Informed consent edge cases:

Patient safety bundles:

Transition-of-care risks (Step 3 favorite):

Health equity:

Mandatory reporting:

Privacy/confidentiality:

Step 3 management: A postpartum woman declines BP medication at discharge despite BP 158/98. Assess understanding, address barriers (cost, side effects, lactation concerns), offer alternatives, document shared decision-making, provide home BP cuff and 72-hour follow-up, and notify PCP — autonomy is preserved while risk is mitigated.

Board pearl: Failure to treat severe-range BP within 60 minutes is a sentinel event and a frequent malpractice claim.

High-Yield Associations and Rapid-Fire Clinical Facts

— cHTN no meds: 38–39+6

— cHTN on meds: 37–39

— Superimposed preeclampsia no severe features: 37

— Severe features: 34

CHAP trial (2022): Treat mild cHTN to <140/90 → fewer adverse outcomes, no increase in SGA

Aspirin 81 mg from 12–28 weeks → reduces preeclampsia in cHTN

First-line antihypertensives: labetalol, nifedipine ER, methyldopa

Contraindicated: ACEi, ARB, aliskiren, MRAs, atenolol, nitroprusside

Severe-range BP (≥160/110) treated within 30–60 minutes with IV labetalol, IV hydralazine, or PO IR nifedipine

Magnesium sulfate: seizure prophylaxis in preeclampsia with severe features and eclampsia; does not lower BP

Magnesium toxicity: loss of DTRs (first), respiratory depression, cardiac arrest — calcium gluconate is antidote

Superimposed preeclampsia affects 20–50% of cHTN pregnancies

Delivery timing:

Postpartum BP peaks day 3–6

40% of eclampsia is postpartum

Aspirin contraindications in pregnancy are essentially none at 81 mg dose; bleeding diatheses individualized

ACEi fetopathy: oligohydramnios, renal dysgenesis, skull hypoplasia, limb contractures, pulmonary hypoplasia

Pheochromocytoma: alpha block before beta block

Coarctation: radio-femoral delay

Renal artery stenosis in young woman → fibromuscular dysplasia (string of beads)

Methyldopa adverse effects: depression, sedation, hepatitis, Coombs+ hemolysis

Labetalol contraindications: asthma, decompensated HF, bradyarrhythmia

Nifedipine + magnesium: safe together; monitor

Long-term CV risk: 2× after preeclampsia, even higher with cHTN

Lactation-compatible: labetalol, nifedipine, methyldopa, enalapril, captopril, propranolol

Avoid in lactation: atenolol (concentrates in milk)

Postpartum contraception: avoid combined estrogen; use progestin-only or LARC

Postpartum BP recheck: 72 hours and 7–10 days

CCS pearl: Always order continuous fetal monitoring whenever you initiate IV antihypertensives in a viable gestation — placental perfusion changes can cause fetal bradycardia.

Board pearl: A patient on enalapril at 9 weeks gestation → stop drug, switch to labetalol, anatomy US at 18–20 weeks, serial amniotic fluid assessment — and document teratogen counseling.

Board Question Stem Patterns

— 32-yo G2P1 on lisinopril presents for first prenatal visit at 8 weeks, BP 138/86. Next step?

— Answer: Discontinue lisinopril, start labetalol or nifedipine ER, start ASA at 12 weeks, baseline labs.

— 28-yo at 14 weeks with cHTN, BP 144/92, asymptomatic. Best management?

— Answer: Initiate antihypertensive to target <140/90 (post-CHAP era); "lifestyle alone" is wrong.

— 30-yo at 30 weeks with cHTN, now BP 168/112, headache. Next step?

— Answer: IV labetalol or hydralazine within 30–60 min, magnesium sulfate, admit L&D, betamethasone, MFM.

— cHTN gravida at 33 weeks with new UPCR 0.8 (was 0.1), platelets 92k, AST 110. Diagnosis and step?

— Answer: Superimposed preeclampsia with severe features; deliver after stabilization and steroids if <34 weeks.

— Day 5 postpartum BP 175/110, severe headache. Best next step?

— Answer: IV labetalol, magnesium, neuroimaging if focal deficits, admit.

— Young gravida with cHTN, hypokalemia, refractory BP. Workup?

— Answer: Defer aldosterone:renin in pregnancy; rule out pheochromocytoma with plasma metanephrines now (safe and lethal if missed); renal Doppler.

— cHTN gravida at 11 weeks. Preventive med to start?

— Answer: ASA 81 mg starting at 12 weeks until delivery.

— Postpartum cHTN, breastfeeding, also diabetic with proteinuria. Best agent?

— Answer: Enalapril or captopril (lactation-compatible, renal-protective).

— cHTN well-controlled on labetalol monotherapy. When deliver?

— Answer: 37 0/7 to 39 0/7 weeks.

— Patient on Mg infusion now with absent DTRs, RR 8. Action?

— Answer: Stop magnesium, give IV calcium gluconate, supportive ventilation.

Pattern 1 — "Switch the ACEi":

Pattern 2 — "CHAP threshold":

Pattern 3 — "Severe-range BP":

Pattern 4 — "Superimposed preeclampsia":

Pattern 5 — "Postpartum stroke prevention":

Pattern 6 — "Secondary HTN clue":

Pattern 7 — "Aspirin candidate":

Pattern 8 — "Lactation drug":

Pattern 9 — "Delivery timing":

Pattern 10 — "Magnesium toxicity":

Step 3 management: When in doubt on a stem, default to treat to <140/90, aspirin, MFM consult, fetal surveillance, and lactation-safe postpartum regimen.

One-Line Recap

Chronic hypertension in pregnancy is BP ≥140/90 before 20 weeks or persisting beyond 12 weeks postpartum, managed with labetalol or nifedipine ER to a target <140/90 (post-CHAP), low-dose aspirin from 12 weeks, intensified fetal and maternal surveillance for superimposed preeclampsia, and a structured postpartum and long-term cardiovascular plan.

Diagnose: HTN before 20 weeks or >12 weeks postpartum; obtain baseline CBC, CMP, UPCR, ECG; rule out secondary causes when red flags present (young age, hypokalemia, paroxysms, refractory disease).

Treat: Stop ACEi/ARB/MRAs; start labetalol or nifedipine ER to target <140/90 (CHAP trial); add ASA 81 mg from 12 weeks; reserve methyldopa as second-line; treat severe-range BP within 30–60 minutes with IV labetalol, IV hydralazine, or PO IR nifedipine; add magnesium sulfate for seizure prophylaxis in superimposed preeclampsia with severe features.

Surveil: Serial labs every 4 weeks from 24 weeks, growth ultrasounds every 4 weeks from 28 weeks, antenatal testing from 32–34 weeks, home BP monitoring throughout; deliver 37–39 weeks if well-controlled, earlier for superimposed preeclampsia or severe features.

Transition: Postpartum BP checks at 72 hours and 7–10 days; switch to lactation-compatible long-term regimen (ACEi if proteinuric/DM); avoid combined estrogen contraception; arrange PCP handoff for lifelong CV risk reduction; counsel on aspirin and preconception optimization for future pregnancies.

Board pearl: Three numbers to memorize — <140/90 BP target, 81 mg aspirin from 12 weeks, treat severe-range BP within 60 minutes — capture the modern Step 3 management of chronic hypertension in pregnancy.