Since more women are postponing having children until later in life, the unfortunate experience of being diagnosed with cancer during pregnancy is still very rare but happening more often. Finding out you have cancer is a very upsetting event under any circumstance, but if you are pregnant, worrying about your baby can be especially scary. In some cases therapy (chemotherapy or radiation) could be harmful to your baby. Your care plan will be individualized to what type of cancer you have and how far along you are in your pregnancy. If you have a slow-growing cancer, you may not need chemotherapy right away. Your care provider may monitor your cancer carefully so you can wait to start treatment. If waiting is not an option, your oncologist and your obstetrician will advise you on the best options.
There have not been very many studies that look at the effects of chemotherapy in the first trimester. This is because very few women are diagnosed with cancer during this period, and of those that are, many choose to end pregnancy or are able to delay chemotherapy. The use of chemotherapy during the 2nd and 3rd trimester has not been associated with birth defects but may increase the risk of low birth weight and stillbirth. If you need surgery, it may be safe to do so while pregnant. Radiation treatment may also be a part of your care plan, particularly if your cancer is in your head, neck or extremities, allowing your baby to be shielded from the radiation.
If you have been diagnosed with cancer and will require treatment, you may wish to delay your plans for childbearing. It is important to have a conversation with your healthcare provider to discuss your unique circumstances. This will inform you about risks for you to consider while making your decision. Women who need radiation or chemotherapy that could affect ovarian function may choose to bank eggs or embryos, before receiving treatment, for future in vitro fertilization.
Usually, women taking chemotherapy after delivery should not breastfeed their babies. There is not enough research to know whether these drugs are safe for the baby. There are some exceptions that your oncologist can advise you about.