Breast cancer touches the lives of almost all Americans. One in eight women will be diagnosed with breast cancer in her lifetime, making it the most common cancer in the United States. While most new cases occur in postmenopausal women, 19% of cases are in younger women of childbearing age.
For breast cancer patients who still want to expand their families, it can be overwhelming and stressful to juggle a new diagnosis and new treatment options with concerns about future fertility and pregnancy.
As a Reproductive Endocrinologist, I work with patients with newly diagnosed cancer to discuss options for preserving fertility, so that each woman can achieve her family building goals. Fortunately, in the midst of a battle with this terrible blind disease, there is hope for the future. We have many ways to help women with cancer grow their families.
Here’s what I want women to know about fertility and pregnancy after breast cancer.
It is an unfortunate fact that during cancer treatment, chemotherapy can damage and deplete a woman’s eggs, making future conception more difficult. The risk to future fertility of a cancer survivor depends on the type and dose of medication, as well as the age of the patient at the time of treatment. And while you’re on cancer treatment and recovering, getting pregnant can get more complicated with each year you are late, due to the effects of age on fertility.
However, there are several ways to preserve your fertility before undergoing treatment for breast cancer.
Preserving fertility after breast cancer
Egg freezing is a process in which mature eggs are removed from the ovaries and frozen for potential use in the future. In order to freeze the eggs before breast cancer treatment, a woman takes injectable drugs to stimulate the ovaries for 10 to 14 days. The goal is to ripen several eggs simultaneously, which will then be collected during an egg retrieval procedure and frozen in the embryology laboratory.
Since many forms of breast cancer are sensitive to estrogen, and a woman’s estrogen levels usually increase during an ovarian stimulation cycle, a drug called Letrozole may also be given to reduce exposure. the body to estrogen for the duration of treatment.
When a woman decides to use frozen eggs in the future to create a pregnancy, they are thawed and fertilized with sperm to create embryos, which can then be transferred to the uterus and / or genetically tested.
This process can be started very quickly and at any point in a woman’s menstrual cycle, so as not to delay treatment for breast cancer. Many patients will complete their cycle between breast surgery and chemo / radiotherapy.
Some women with partners will choose to freeze embryos before cancer treatment. The initial part of the process is the same as egg freezing, but after ovarian stimulation and egg retrieval, the sperm is used to fertilize the eggs to create embryos. These embryos are cultured in the laboratory and are usually frozen at the blastocyst stage (day 5).
Blastocyst embryos can be tested for chromosomal abnormalities, or even for carcinogenic genes such as BRCA in women who have a genetic predisposition to cancer.
Cryopreservation of ovarian tissue
Women who urgently need to start cancer treatment and do not have time for an egg or embryo freezing cycle also have the option of cryopreserving ovarian tissue.
Laparoscopic surgery is done to remove part of an ovary, and this tissue is broken into pieces and frozen for the future. Then, when a woman is ready to attempt pregnancy, a piece of frozen ovarian tissue is thawed and surgically transplanted to her existing ovary. Some of these tissue transplants will become hormonally active and ovulate in the future.
This method was considered experimental until recently, but today more than 130 babies have been born into the world from ovarian tissue transplantation.
During chemotherapy treatment, drugs called GnRH agonists may be given to suppress a woman’s hormones. This keeps the ovaries “silent” to make the eggs less susceptible to damage. This medicine may reduce the chances of going into menopause during cancer treatment, but is somewhat controversial.
It does not replace the other fertility preservation methods listed above but can be administered in addition to these treatments.
Pregnancy after breast cancer
Planning for pregnancy after breast cancer
Deciding when to get pregnant after cancer treatment is complex and influenced by many factors. The type and stage of cancer and the need for continued treatment all play a role in determining a safe time to conceive. It is always important for women to discuss these issues with their oncologist before starting pregnancy.
Most of the time, patients are advised to wait at least a few years after completing treatment before trying to conceive. Sometimes, if a cancer is sensitive to estrogen and long-term hormone suppression is needed, the recommendation may be to wait much longer.
For women with estrogen-sensitive cancers and / or for women taking long-term hormone suppression to reduce the risk of recurrence, another option is to start a family with the help of a surrogate, also known as the name of the surrogate mother.
An embryo created before cancer treatment (or an embryo created afterwards with previous frozen eggs) can be transferred to the uterus of a surrogate mother, who carries the pregnancy but has no other biological relationship to the baby. . This option helps build a healthy and safe family in women who are at high risk of cancer recurrence during pregnancy.
Other ways to grow your family after cancer
Women who do not preserve their fertility before cancer treatment also have other options to expand their families. If they do not conceive on their own, they can use a donated egg or embryo to get pregnant, or they can continue adoption.
The hope of a future family building
A new diagnosis of breast cancer can create understandable feelings of fear and uncertainty about the future, especially for premenopausal women hoping to expand their families.
Fortunately, women of childbearing age who are diagnosed with breast cancer have many options to make their dreams of motherhood come true. My patients who continue to freeze eggs and embryos often report that the experience is hopeful and uplifting during an otherwise difficult time. It is an honor to help every cancer patient safely and successfully start a family.
Blumenfeld Z. Preservation of fertility using GnRH agonists: rationale, possible mechanisms and explanation of the controversy. Overview of clinical medicine: Reproductive health. Aug 13, 2019: 1179558119870163. doi: 10.1177% 2F1179558119870163
MF Garrido-Oyarzun, Castelo-Branco C. Controversies over the use of GnRH agonists to reduce chemotherapy-induced gonadotoxicity. Climacteric. 2016 Nov 1; 19 (6): 522-5. doi: 10.1080 / 13697137.2016.1225713
A version of this article was originally posted on October 29, 2020. It has been updated.