A breast cancer diagnosis during pregnancy is rare but it happens. Around one in 3,000 pregnancies is affected. When it does, two questions come immediately: is treatment possible without harming the baby, and does pregnancy make the cancer worse? The answer to both is more reassuring than most women expect. Treatment is possible. In many cases it proceeds without terminating the pregnancy. But it requires a specialist team and very careful timing of every step.
According to Dr. Garvit Chitkara, a trusted Breast Cancer Surgeon in Mumbai,
“Pregnancy-associated breast cancer is one of the most emotionally difficult situations a woman can face. What I tell patients is that treatment does not have to wait and the pregnancy does not have to end. Surgery is safe in all three trimesters. Chemotherapy can be given from the second trimester onward. The key is a fast, coordinated plan involving the oncology team, the obstetrician, and the patient together.”
What treatments are safe during pregnancy?
The safety of each treatment depends heavily on gestational age. Some are safe across all trimesters. Others have a clear window:
- Surgery is safe in all trimesters. It is the first-line treatment for most pregnancy-associated breast cancers. General anaesthesia carries a low risk to the foetus when performed by an experienced team with foetal monitoring. Lumpectomy or mastectomy can proceed without delay regardless of trimester.
- Chemotherapy after the first trimester. The first trimester is the period of foetal organ development. Chemotherapy during this window carries the highest risk of foetal malformation and pregnancy loss. From the second trimester onward, certain chemotherapy regimens are considered safe and are used routinely in pregnancy-associated breast cancer globally.
- Radiation is deferred until after delivery. Whole breast radiation cannot be safely given during pregnancy without unacceptable foetal radiation exposure. It is planned for after the baby is born, which is why timing of delivery is factored into the overall treatment plan.
- Hormone therapy and HER2-targeted therapy are not used during pregnancy. Tamoxifen carries teratogenic risk. Trastuzumab is associated with foetal renal complications. Both are started after delivery and breastfeeding is complete.
For women whose diagnosis requires surgical intervention first, the breast cancer surgery page outlines the procedures available.
Could a breast cancer diagnosis during pregnancy still be treated safely?
What does diagnosis and monitoring look like during pregnancy?
Getting to a diagnosis and managing the pregnancy alongside treatment requires a structured approach:
- Biopsy is safe during pregnancy. Core needle biopsy under local anaesthesia carries no meaningful risk to the pregnancy and should not be delayed. Diagnosis must be confirmed before any treatment decision is made.
- Imaging is modified but still possible. Ultrasound is the preferred imaging tool during pregnancy. Mammography can be performed with abdominal shielding. MRI without gadolinium contrast is safe. CT and bone scans with radioactive tracers are avoided where possible or deferred.
- Foetal monitoring throughout chemotherapy. When chemotherapy is given during pregnancy, regular foetal growth scans and cardiotocography are done to monitor for any adverse effects. Early delivery may be planned to allow completion of treatment sooner.
- Delivery timing is coordinated with the oncology team. Where possible, delivery is planned to allow a gap of at least three weeks between the last chemotherapy dose and birth, reducing the risk of neonatal bone marrow suppression at delivery.
Understanding how chemotherapy works in breast cancer treatment is important context for pregnancy-associated cases. The breast cancer chemotherapy blog covers the specifics of how and when it is used.
Why Choose Dr Garvit Chitkara ?
Dr. Garvit Chitkara is Associate Director of Breast Surgical Oncology and Oncoplasty at Nanavati Max Institute of Cancer Care, Mumbai, with 17 years of experience in breast surgical oncology. He works within a multidisciplinary team to manage complex cases including pregnancy-associated breast cancer, where surgical timing, systemic treatment sequencing, and obstetric coordination all need to run in parallel. To book a consultation, call +91 91673 28325.
FAQ
Does breast cancer grow faster during pregnancy?
Pregnancy itself does not cause breast cancer to grow faster. However, hormonal changes can make breast tissue denser, which can delay detection. Cancers found during pregnancy tend to be diagnosed at a later stage simply because symptoms are often attributed to normal pregnancy changes.
Can I breastfeed after breast cancer treatment during pregnancy?
Breastfeeding from the treated breast after lumpectomy and radiation may be limited or not possible. From the untreated breast it is generally possible. Hormone therapy and targeted HER2 therapy must be completed before breastfeeding begins.
Should I terminate the pregnancy if I am diagnosed with breast cancer?
In most cases termination is not medically necessary. Current evidence does not show that terminating the pregnancy improves cancer outcomes. This is a deeply personal decision and should be made with full information and specialist guidance, not assumed to be required.
Is the baby at risk from chemotherapy given during pregnancy?
Chemotherapy given from the second trimester carries a low but real risk of preterm labour and low birth weight. Major structural abnormalities are not expected with regimens used in pregnancy. Newborns are monitored closely after delivery.
