Pheochromocytoma and Pregnancy: Essential Facts for Expecting Mothers

When a woman discovers she’s pregnant and is also diagnosed with pheochromocytoma, the news can feel overwhelming. This rare adrenal tumor releases large bursts of catecholamines that drive sudden spikes in blood pressure, heart rate, and sweat. Understanding how the condition behaves in pregnancy, spotting warning signs early, and coordinating a safe treatment plan are the three pillars that protect both mother and baby.

What Is Pheochromocytoma and How Common Is It in Pregnancy?

Pheochromocytoma is a catecholamine‑producing tumor that originates in the adrenal medulla. While it accounts for less than 0.2 % of all hypertensive disorders, its prevalence rises to roughly 1 in 5,000-10,000 pregnancies. Because the tumor can remain silent for years, many women only discover it when blood pressure becomes uncontrollable during routine prenatal visits.

The hormonal shifts of pregnancy-especially the rise in estrogen and increased plasma volume-can amplify catecholamine effects, making crises more likely in the third trimester. That’s why obstetricians and endocrinologists treat any pregnant patient with a confirmed tumor as high‑risk.

Key Symptoms and How Doctors Diagnose the Condition

Typical signs overlap with common pregnancy complaints, which is why a high index of suspicion is crucial. Look for:

• Paroxysmal hypertension (sudden BP > 160/100 mmHg) that doesn’t respond to standard antihypertensives.
• Palpitations, pounding headache, or profuse sweating that appear in episodes.
• Chest pain or anxiety attacks that seem out of proportion to normal pregnancy discomfort.

If these patterns emerge, clinicians will order biochemical testing. A 24‑hour urine collection or plasma free metanephrine assay is the gold standard, with sensitivity above 95 %.

Imaging follows biochemical confirmation. Magnetic resonance imaging (MRI) without gadolinium is preferred because it avoids ionizing radiation, while abdominal ultrasound can offer a quick bedside view.

Maternal and Fetal Risks Without Proper Management

Uncontrolled pheochromocytoma carries serious stakes. Maternal mortality rates can reach 15 % in untreated cases, mainly due to hypertensive emergencies, stroke, or cardiac arrhythmias. For the fetus, risks include:

• Intrauterine growth restriction (IUGR) from chronic placental hypoperfusion.
• Preterm birth triggered by maternal crisis.
• Neonatal catecholamine overload leading to respiratory distress.

These outcomes underscore why multidisciplinary care-linking obstetrics, endocrinology, anesthesia, and neonatology-is the standard of care.

Medical Management: Which Drugs Are Safe During Pregnancy?

Controlling catecholamine surges is the first therapeutic goal. Alpha‑blockers are the cornerstone, with phenoxybenzamine or the shorter‑acting prazosin commonly used. Starting at a low dose and titrating every 2-3 days helps avoid reflex tachycardia.

Once adequate alpha‑blockade is achieved (usually after 7-10 days), beta‑blockers such as labetalol or propranolol can be added to blunt heart‑rate spikes. Beta‑blockers must never precede alpha‑blockade; doing so can cause unopposed alpha‑vasoconstriction and a dangerous BP surge.

For patients with refractory hypertension, Metyrosine-a tyrosine‑hydroxylase inhibitor-may be tried, but data on fetal safety are limited, so it’s reserved for life‑threatening cases.

Throughout the medical regimen, daily home BP monitoring and frequent lab checks for electrolytes and glucose are essential. Adjustments often occur at each prenatal visit.

Surgical Options: When Is Adrenalectomy Feasible?

Definitive removal of the tumor via laparoscopic adrenalectomy offers the best long‑term cure, but timing is critical. The consensus among endocrine surgeons is:

If a crisis occurs in the third trimester, emergent surgery may be needed, but most teams aim to stabilize with medication and schedule a Cesarean delivery followed by immediate tumor excision.

Delivery Planning: Vaginal Birth vs. Cesarean Section

Both delivery routes are possible, but the choice hinges on tumor control and anesthetic safety. When alpha‑blockade is adequate and BP is stable, a carefully monitored vaginal delivery can proceed, often with an epidural to blunt sympathetic responses.

However, many specialists prefer a scheduled Cesarean section at 36‑38 weeks for several reasons:

• Allows a controlled environment for rapid conversion to surgery if a hypertensive crisis erupts.
• Reduces the stress of labor‑induced catecholamine surges.
• Facilitates immediate postoperative monitoring of both mother and newborn.

An experienced obstetric anesthesiologist will use short‑acting agents like etomidate and nitroprusside to keep blood pressure steady during induction.

Postpartum Care and Long‑Term Follow‑Up

Even after a successful delivery and tumor removal, vigilance doesn’t end. Follow‑up includes:

1. Weekly BP checks for the first month, then monthly for six months.
2. Plasma metanephrine levels at 6‑week and 6‑month intervals to confirm remission.
3. Genetic counseling if the tumor is linked to MEN 2, VHL, or NF1 syndromes.
4. Breast‑feeding considerations: most alpha‑ and beta‑blockers are compatible, but phenoxybenzamine is usually avoided.

Because recurrence can occur years later, lifelong annual screening is recommended, especially for women with a family history of endocrine tumors.

Checklist: What to Discuss With Your Care Team

• Current BP trends and medication side‑effects.
• Timing of biochemical testing and imaging results.
• Preferred delivery method and anesthesia plan.
• Plan for immediate postoperative monitoring of the newborn.
• Genetic testing options and implications for future pregnancies.

Bring this list to each appointment; clear communication reduces the chance of a surprise crisis.

Frequently Asked Questions

By staying informed, collaborating with a dedicated care team, and following a clear plan, most women with pheochromocytoma can look forward to a safe pregnancy and a healthy baby.