Cancer in Pregnancy: Balancing Two Patients, One Course of Care

FIGO’s new best practice advice reframes oncologic care in pregnancy as a multidisciplinary, ethically integrated field—not an exception.

Cancer in pregnancy is no longer a rarity. Each year, an estimated 1 in 1,000 pregnancies involves a malignancy, with breast, cervical, thyroid, and hematologic cancers leading the list. Until recently, the reflexive response was termination. FIGO’s new 2025 best practice review moves decisively away from that model, arguing that pregnancy should not automatically preclude standard oncologic care. Instead, the report reframes treatment through the principles of maternal autonomy, fetal protection, and interdisciplinary balance.

Reconsidering “Incompatibility”

For decades, the phrase “incompatible with pregnancy” governed how clinicians viewed malignancy. The new FIGO narrative review, led by Nanda and colleagues, rejects that binary.

Most cancers can be treated during pregnancy if therapy is adapted to gestational stage and maternal stability. Termination may remain necessary in rare instances—especially when diagnosis occurs early and treatment delay would significantly worsen prognosis—but the default assumption has shifted toward continuation with modified therapy.

FIGO emphasizes individualized risk–benefit analysis, co-management by obstetrics, oncology, neonatology, and ethics teams, and transparent counseling so that women can make informed decisions without coercion. The fetus is now recognized as a co-patient, but not a barrier to maternal treatment.

The Major Cancers Encountered During Pregnancy

Breast cancer. The most common malignancy in pregnancy, typically diagnosed in the second or third trimester. Ultrasound and MRI without gadolinium are preferred for evaluation. Surgery is safe in all trimesters, and anthracycline-based chemotherapy after 14 weeks carries low fetal risk. Radiotherapy and endocrine therapy are deferred until postpartum. Prognosis parallels that of non-pregnant women when treatment is not delayed.

Cervical cancer. Often detected through abnormal cytology or incidental findings at prenatal visits. Early-stage disease may allow continuation of pregnancy with delayed surgery or neoadjuvant chemotherapy. Radical surgery or chemoradiation requires pregnancy termination if undertaken early. Delivery by cesarean is indicated when tumor size or location risks dissemination.

Ovarian cancer. Usually discovered incidentally during obstetric imaging or surgery. Most are borderline or early epithelial tumors. Surgical staging is feasible in the second trimester. Platinum-based chemotherapy can be given later in gestation if indicated. Prognosis depends on stage and histology, not pregnancy per se.

Thyroid cancer. The most frequent endocrine malignancy associated with pregnancy, often well-differentiated papillary carcinoma. Because progression is slow, surgery can usually wait until after delivery unless there is compressive growth or rapid progression. Radioiodine therapy is contraindicated during pregnancy and lactation.

Melanoma. Can progress rapidly under hormonal influence, though data are mixed. Excisional surgery is safe at any gestational age. Systemic therapy, including immunotherapy or targeted therapy, is contraindicated during pregnancy. Vertical transmission is rare but documented, necessitating placental histology after delivery.

Hematologic malignancies (leukemia and lymphoma). Require urgent evaluation because untreated disease poses high maternal risk. Anthracycline-based regimens can be used after the first trimester; methotrexate and other antimetabolites are avoided. Radiation to nodal areas may be possible with shielding in late pregnancy. Supportive transfusions and infection prophylaxis are essential.

Colorectal and gastrointestinal cancers. Increasingly diagnosed as maternal age rises. Symptoms often mimic pregnancy, causing diagnostic delay. Surgical resection is generally feasible; chemotherapy (FOLFOX-based) may be used in later trimesters with caution. Endoscopic procedures with limited sedation are safe when indicated.

Brain tumors. Gliomas and meningiomas may enlarge under hormonal influence and fluid shifts. MRI is diagnostic; surgical decompression can be lifesaving. Certain chemotherapies cross the placenta and are deferred until postpartum. Close neurologic and obstetric collaboration is vital for timing of delivery and anesthesia.

Hodgkin lymphoma. One of the better-studied cancers in pregnancy, with ABVD chemotherapy (doxorubicin, bleomycin, vinblastine, dacarbazine) considered relatively safe after the first trimester. Radiotherapy is postponed. Maternal outcomes are comparable to non-pregnant cases when treated promptly.

Timing Matters More Than Diagnosis

Gestational age determines therapeutic feasibility.

Chemotherapy, once categorically avoided, can be administered safely after the first trimester in many regimens. Anthracyclines and taxanes have shown reassuring data when timed appropriately. Radiation remains contraindicated in early pregnancy but can be considered in later gestation with strict shielding and dosimetry limits. Surgery, if indicated, is generally safe in all trimesters.

The ethical pivot is clear: “delay if possible, treat if necessary, terminate only if essential.” FIGO urges that diagnostic delay, often caused by fear of fetal harm or medicolegal anxiety, poses its own risk of maternal—and ultimately fetal—harm.

Diagnostics and Imaging: Clarity Over Fear

Modern imaging allows precise staging with minimal fetal exposure. MRI is safe throughout pregnancy; ultrasound remains first-line. When CT or PET is required, the fetal dose can often be kept below teratogenic thresholds. FIGO’s guidance calls for rational, evidence-based reassurance rather than reflex avoidance.

Ethically, the report underscores the importance of truth-telling: pregnant women must be given accurate radiation risk estimates rather than vague admonitions to “wait.” A misplaced instinct to protect the fetus through ignorance can compromise both lives.

Ethical Integration, Not Ethical Evasion

The review explicitly situates its clinical advice within the framework of medical ethics.

The primary obligations—respect for autonomy, beneficence, nonmaleficence, and justice—apply simultaneously to both patients. Clinicians are urged to avoid “hierarchical ethics,” where fetal interests are automatically prioritized over maternal rights.

Instead, informed consent should rest on transparent communication about prognosis, options, and uncertainties.

The report’s moral clarity is noteworthy: respecting a pregnant woman’s decision to continue treatment, even at some fetal risk, is not a failure of fetal advocacy. It is an affirmation of professional integrity.

Delivery and Neonatal Outcomes

When cancer and pregnancy coexist, delivery timing becomes strategic. Preterm induction for convenience or to accelerate maternal treatment is no longer acceptable. Unless disease progression mandates early intervention, gestation should continue to term. Neonatal outcomes improve dramatically with every additional week after 34 weeks.

The report highlights that chemotherapy exposure late in pregnancy has not been associated with higher congenital anomaly rates but may transiently suppress neonatal hematopoiesis. Coordinated delivery planning, with at least three weeks between the last chemotherapy dose and birth, minimizes complications.

Here again, ethics and evidence converge: the goal is not fetal survival at any cost, but optimizing both maternal and neonatal futures through careful coordination.

Fertility, Future Pregnancy, and Long-Term Outlook

An often-overlooked dimension is survivorship. FIGO calls for counseling about fertility preservation and future pregnancy risks, integrating reproductive endocrinology early in the care continuum. As survival rates improve, attention must shift from immediate cure to life after cancer—including psychological support and family planning.

This patient-centered perspective marks another ethical evolution: pregnant women with cancer are no longer seen as tragic exceptions, but as mothers deserving the same continuum of care as any oncology patient.

The Multidisciplinary Imperative

The FIGO document is, above all, a call for institutional readiness. Management should never depend on the conviction of an individual obstetrician. Every tertiary center should have a standing tumor board that includes MFM specialists, oncologists, anesthesiologists, neonatologists, and ethicists. Hospitals must ensure access to rapid consultation and psychosocial support.

This is both a safety and a justice issue. Women should not have to travel or terminate a wanted pregnancy due to institutional inexperience.

Reflection

Medicine has finally caught up with reality: pregnancy does not suspend a woman’s right to comprehensive cancer treatment. The new FIGO guidance demands not only technical coordination but moral maturity. Each case is a test of whether we truly mean it when we say “patient-centered care.” For these women, there are two patients—but one ethical standard.