Cancer During Pregnancy: Diagnosis & Care

Being diagnosed with cancer while pregnant is rare, and it is one of the situations where people are most likely to be given bad information by well-meaning friends and by the internet. The most common assumption — that treatment is impossible and the pregnancy must end — is not what modern cancer care assumes. Many cancers can be treated during pregnancy, and many pregnancies continue to a healthy delivery.

What is true is that the decisions are genuinely complicated, they are made by a larger team than usual, and they belong to the pregnant person.

Pregnancy makes cancer harder to spot. Breast tissue changes, fatigue, nausea, bleeding and abdominal pain all have ordinary pregnancy explanations, so symptoms are frequently attributed to the pregnancy first. A lump or a symptom that does not resolve deserves investigation rather than reassurance, and pregnancy is not a reason to skip a workup.

Imaging is possible, with adjustments. Ultrasound and MRI without contrast are generally the first choices because they involve no ionizing radiation. Other scans may still be used when the information matters, sometimes with shielding or modified protocols, and a radiologist can advise on the expected exposure. Biopsies are routinely performed during pregnancy. The point of staging is the same as at any other time: to know what is being treated before deciding how.

Ask what each test would change, and whether a lower-exposure alternative answers the same question.

Care during pregnancy is not run by one doctor. Expect a maternal-fetal medicine specialist alongside your oncologist, plus a neonatologist, an obstetric anesthesiologist, a pharmacist, and often a social worker or ethicist. The American Society of Clinical Oncology published a guideline on managing cancer during pregnancy in 2025, describing it as bringing together maternal-fetal medicine and medical oncology, and covering everything from the timing of diagnostic tests through delivery planning and the ethical and legal questions involved.

That guideline also addresses something that often goes unspoken: it includes recommendations to support a patient's decision either to continue or to end a pregnancy, and notes that access to that choice differs by state. Whatever you decide, you are entitled to a clear explanation of what continuing the pregnancy would mean for your treatment, and what ending it would and would not change about your prognosis.

Questions worth asking the whole team together, in one room:

• Can this cancer be treated effectively without delaying treatment, and what does waiting cost?
• Which specific drugs are being proposed, and what is known about each in pregnancy?
• Is delivery timing being driven by my treatment, by the baby's development, or both?
• Who is coordinating between oncology and obstetrics, and who do I call first with a problem?
• What follow-up will the baby have after birth?

Our general list of questions to ask before treatment begins can be adapted for this conversation.

Some broad patterns hold across cancer types, though specifics depend entirely on the diagnosis and the stage of pregnancy.

Surgery can usually be performed during pregnancy, with anesthetic and monitoring adjustments, and the second trimester is often the most straightforward window.

Chemotherapy is a different question in the first trimester than later. Writing about cervical cancer treatment during pregnancy, the National Cancer Institute states that chemotherapy given in the second or third trimester does not usually harm the fetus, while chemotherapy is unsafe during the first trimester. The same page notes that radiation therapy is harmful throughout fetal development. Newer drug classes, including many targeted therapies and immunotherapies, have much less pregnancy data behind them, and your team should say plainly when the honest answer is that the evidence is limited.

Delivery timing becomes part of the treatment plan. Teams generally try to avoid delivering very early solely for treatment reasons, and to schedule delivery away from recent chemotherapy so that blood counts have recovered. Some treatments are held until after birth, some are given before. Whether breastfeeding is possible depends on the specific drugs involved, so ask about it in advance rather than afterward.

This is a lonely diagnosis, because the two groups you would normally lean on — other pregnant people and other cancer patients — are each having a very different experience. Hope for Two, also known as the Pregnant with Cancer Network, connects people who have been through cancer during pregnancy with those going through it now. Our support page has other starting points.

You will hear a great deal of confident opinion from people who have never encountered this situation. The team in front of you, with your full history and your stated priorities, is a better guide than any of it.