Cancer During Pregnancy
Cancer during pregnancy is rare, but it can happen. Fortunately, cancer rarely affects the baby directly, so pregnant women with cancer can still give birth to healthy babies. Nevertheless, the management of cancer during pregnancy is extremely complicated, so it’s important to find a health care team with extensive experience in treating pregnant women with cancer.
In some cases, normal prenatal tests can help reveal cancer that might have otherwise gone undetected until a much later time. For example, ovarian cancer might be diagnosed during a pregnancy-related ultrasound, or cervical cancer might be detected during a prenatal Pap test.
However, pregnancy can sometimes delay a cancer diagnosis because many of the cancer- and pregnancy-related symptoms overlap. For example, frequent headaches, breast swelling (or symptoms of mastitis), abdominal bloating and rectal bleeding are all common during pregnancy. So while also signs of cancer, they’re not considered suspicious when they develop in pregnant women.
The most common type of cancer diagnosed during pregnancy is breast cancer, but other types include cervical cancer, melanoma, thyroid cancer, leukemia and lymphoma.
Traditional diagnostic imaging tests are often used to help doctors diagnose cancer (see Imaging), and most (including MRI, ultrasound and biopsy) are generally safe for use on pregnant women. Other tests that use ionizing radiation – including X-rays and CT scans – can often still be used, depending on the area of the body to be scanned.
It’s important to find a doctor with experience treating women who have been diagnosed with cancer during or soon after their pregnancy. Don’t hesitate to seek a second opinion when considering treatment options.
Not all cancer treatments are safe for pregnant women, so doctors must consider both the mother and the baby when choosing a treatment plan. Several factors are examined, including the type, size, location and stage of the cancer; the stage of the pregnancy (gestational age of the baby); and the wishes of the expectant mother.
During the first trimester (first three months of pregnancy), certain cancer treatments have a greater chance of harming the baby. Therefore, doctors may choose to delay the start of treatment until the second or third trimester. If the expectant mother is already in the second or third trimester, doctors may wait to start treatment until after the baby is born. They also may choose to induce labor early.
The most common treatment plans for pregnant women with cancer include surgery and chemotherapy. Radiation therapy is typically avoided because the ionizing radiation can harm the baby. (See Treatment for more information)
Surgery is considered the safest treatment option during all stages of pregnancy, as it poses little risk to the developing baby. During the second and third trimesters, chemotherapy is also considered a safe option. The placenta (temporary organ that connects the mother and baby) creates a barrier around the baby, through which some types of chemotherapy drugs cannot pass; this leaves the baby directly unaffected. However, some types of chemotherapy may still cause indirect harm to the baby. Certain side effects that may impact the mother, such as anemia and malnutrition, may pose a threat to the baby, and chemotherapy drugs also have the potential to cause early labor and low birth weight. The use of chemotherapy during the first trimester is generally discouraged, as it can result in birth defects or miscarriage.
Questions to ask your doctor
It is important to maintain an open dialogue with your health care team during your cancer journey, especially if you are pregnant. These questions can help you start the conversation:
- Do you have any experience treating pregnant women with cancer?
- What type of treatment do you recommend?
- Can I start treatment right away, or should it be delayed?
- What are the risks of treatment for me and my baby?
- What are the risks of delaying treatment?
- How will treatment affect my delivery?
- Will treatment affect my ability to breast-feed?
- What support services and resources do you recommend?
Breast-feeding with cancer is another important issue to consider. Cancer cells cannot be passed to your baby through breast milk. However, chemotherapy drugs and certain radioactive components can get into breast milk and harm the baby. Therefore, women who have cancer and are being treated with chemotherapy or radiation therapy are generally discouraged from breast-feeding.