Chemotherapy and pregnancy

Chemotherapy is the most common treatment used during pregnancy. The drugs destroy cancer cells, but they also affect healthy cells. It is natural to feel anxious about the possible effects of chemotherapy on the baby. But, at the same time, you may want to start treatment for the cancer.

If your doctors think you need chemotherapy, they may:

• delay chemotherapy until after the first trimester
• avoid using a certain drug because it is harmful to the baby
• avoid using a certain drug because there is not enough evidence to show it is safe in pregnancy.

You do not usually have chemotherapy during the first trimester. This is because the baby’s organs are still forming, and chemotherapy can increase the risk of a miscarriage or birth defect.

You can usually start chemotherapy after you are 14 weeks pregnant (in the second trimester). At this stage, research shows most chemotherapy drugs will not harm the baby. The placenta acts as a barrier between you and the baby. Some drugs cannot pass through the placenta. Others only pass through in very small amounts. Your cancer doctor and specialist nurse will explain this to you.

You will usually have chemotherapy as an injection or a drip (infusion) into a vein, or as tablets. This is the same for someone who is not pregnant.

It may be helpful to talk to someone who has also had chemotherapy during pregnancy. Mummy’s Star may be able to arrange this for you. Your cancer team may also help with this.

Your doctors will talk to you about when you will stop chemotherapy. Chemotherapy is not usually given after you are 37 weeks pregnant. You will have a break between your last dose of chemotherapy and your expected delivery date. This is to avoid the baby being born when your blood cell levels are still low. Having a low level of blood cells is a temporary side effect of chemotherapy. It can increase your risk of serious infection and bleeding.

If your baby is born soon after your chemotherapy finishes, doctors can give you drugs to support your immune system. This helps you fight infections.

You may have chemotherapy before or after surgery to remove breast cancer. Doctors will use the same chemotherapy drugs they would give to someone with breast cancer who is not pregnant.

Your doctor will usually give you a combination of:

• doxorubicin (Adriamycin^®)
• cyclophosphamide
• epirubicin.

These drugs used to treat breast cancer during pregnancy.

You might have a drug called docetaxel (Taxotere^®) or paclitaxol (Taxol^®). These are called taxanes. These drugs are less commonly used in pregnancy. You may have them nearer the end of your chemotherapy treatment. This often means you have them after the baby is born.

You might have other treatments after the baby is born. These include radiotherapy, hormonal and targeted therapy.

Chemotherapy can be used to treat fast-growing non-Hodgkin lymphoma (NHL) during pregnancy. CHOP is the standard combination of chemotherapy drugs used. It can be given during pregnancy. It is made up of:

• C – cyclophosphamide
• H – doxorubicin (hydroxydaunomycin)
• O – vincristine (Oncovin^®)
• P – prednisolone (a steroid).

Rituximab is a targeted therapy drug usually given with CHOP. This treatment is called R-CHOP. Doctors usually give it to you after the baby is born.

Chemotherapy is used to destroy all the cancer cells for acute myeloid leukaemia (AML). This is called induction chemotherapy. The drugs that are usually given in this treatment are daunorubicin and cytarabine. You can still have these drugs if you are pregnant.

Acute promyelocytic leukaemia (APL)

A rare type of AML called acute promyelocytic leukaemia (APL) is treated in a different way. The first treatment is a drug called ATRA, which is also called tretinoin or Vesanoid®. ATRA can reduce leukaemia symptoms very quickly. It is usually given with chemotherapy or a drug called arsenic trioxide. You cannot have ATRA during the first 14 weeks of pregnancy.

APL needs to be treated very quickly. There is a risk of having a serious bleed without treatment. Unless it is diagnosed later in pregnancy, doctors may recommend ending the pregnancy. This is so you can have the most effective treatment. If you decide to continue with the pregnancy, ATRA is usually given on its own.