Women who confront a cancer diagnosis before beginning or completing their families may have many questions about how cancer treatment will affect their ability to have children in the future. The good news is that an increasing amount of attention is being devoted to this topic, and there are steps that you may be able to take to preserve your reproductive options. The best time to talk about these issues with your doctor is before cancer treatment begins.
How does cancer treatment affect fertility in women?
Chemotherapy: Many chemotherapy drugs are toxic to the egg cells (oocytes) in the ovaries. If the number of remaining oocytes in the ovaries reaches a critically low point during treatment, women experience “acute ovarian failure.” This means that the ovaries stop functioning during or shortly after cancer treatment. If oocytes are lost during treatment but do not reach this critically low point, women are at risk for early menopause but may still be able to get pregnant for some time after treatment.
Radiation: Radiation to the pelvis can also destroy oocytes. Radiation to the pelvis can also affect uterine growth and blood flow, particularly if received before puberty.[1] A poorly developed uterus may make a woman more likely to have a miscarriage, or more likely to have a preterm or low-birthweight infant.
Surgery: Some cancers require surgical removal of the uterus, the ovaries, or both.
The effects of cancer treatment on fertility can vary substantially by age. Younger women, who have a larger pool of oocytes when they start cancer treatment, are more likely than older women to be able to get pregnant after treatment.[2]
Options for preserving fertility in women
If possible, women should talk with their doctor about their future fertility before beginning cancer treatment. Some options for preserving fertility require that steps be taken before cancer treatment begins.
One of the most established approaches for preserving fertility among female cancer patients is embryo freezing.[3] Before starting cancer treatment, a woman would be given hormones to stimulate the development of eggs in her ovaries. Mature eggs would be removed and fertilized with the sperm of her husband, partner or a sperm donor. The embryos that result from these fertilized eggs would be frozen for later use.
Although embryo freezing is an established approach to helping women become pregnant after cancer, there are downsides. A woman may not currently have a male partner and may be unwilling to use an anonymous sperm donor. It’s also important to be aware that embryo freezing takes approximately two weeks after the start of a woman’s period. If a woman needs to begin cancer treatment immediately, she may not be able to go through this process. Finally, this approach is only an option for women of childbearing age; stimulating the ovaries to produce mature eggs is not an option for girls who develop cancer during childhood.
Several other options are still in the experimental phase. One approach being explored is the freezing of unfertilized eggs.3 Once again, the ovaries would be stimulated to produce mature eggs before cancer treatment begins. The eggs would then be frozen without being fertilized by sperm. Currently, freezing unfertilized eggs is less likely to result in pregnancy than freezing embryos, largely because unfertilized eggs are less likely than embryos to survive the process of freezing and thawing. Nevertheless, it may be an option for women who do not have a male partner at the time of their cancer diagnosis, and it avoids the difficult issue of what to do with unused embryos.
Another promising but still experimental approach is to freeze all or a part of an ovary before cancer treatment.[4] After treatment, the ovarian tissue is implanted either back in the woman’s pelvis or in another location (such as under her skin). If this process is successful, the ovarian tissue will begin producing eggs. A safety concern with this approach is the possibility of reintroducing cancer cells along with the ovarian tissue, and the tissue will need to be carefully screened for cancer before it is transplanted.4
Finally, it may also be possible to modify some cancer treatments to minimize their effects on subsequent fertility. For example, shielding the ovaries during radiation, or moving the ovaries out of the radiation field, may protect them from the effects of radiation. Scientists are also exploring whether using drugs to suppress the activity of the ovaries during chemotherapy will make the ovaries less susceptible to damage by chemotherapy.[5] For women with certain types of cervical or ovarian cancer, fertility-preserving surgery may also be an option.[6] It’s important to understand that only specific subsets of patients will be candidates for these approaches, and that some of the methods are still in the early stages of evaluation.
Pregnancy after cancer
In addition to having concerns about their ability to get pregnant, women may have concerns about whether pregnancy after cancer treatment will be safe for themselves and their children. While there is a limited amount of information about these topics, the news is generally good.
The risk of cancer recurrence during or after pregnancy has been most studied in women with breast cancer, and these studies generally have reported that pregnancy does not increase the risk of breast cancer recurrence. [7] Many doctors, however, suggest waiting for a period of time after treatment before becoming pregnant. [8]
If chemotherapy or radiation therapy has damaged her heart or lungs, a woman may also have concerns about the strain that pregnancy will put on her body. Studies of breast cancer survivors suggest that long-term heart problems are uncommon after chemotherapy or radiation therapy, [9] but a woman may wish to talk with her doctor about her current health status and the likely effects of pregnancy.
Children born after their mother’s cancer treatment do not appear to be more likely than other children to have birth defects or cancer.[10] If a woman’s cancer was due to a hereditary cancer syndrome, such as Lynch syndrome (hereditary nonpolyposis colorectal cancer), her child may inherit the gene mutation responsible for her family’s increased risk of cancer. Talking with a genetic counselor may help clarify the child’s risk.
When planning for pregnancy, be aware that some cancer treatments may cause you to have an early menopause even if your periods resume after treatment. Also be aware that you may be capable of conceiving even if your periods do not resume; continue to use birth control if you do not wish to become pregnant.
Other Options for Parenthood
Not all women have the luxury of being able to explore their reproductive options before beginning cancer treatment, and not all women will find a fertility preservation option that meets their needs. But there are still ways to become a parent. Discussion of other routes to parenthood may be a painful topic for women who want to become pregnant and cannot. But as cancer survivors consider how best to build their families, methods such as adoption are important options.
Adoption: Couples and individuals who wish to adopt have a range of options, including different types of domestic and international adoptions. You may wish to start by learning about the adoption laws in your state and by talking with other adoptive parents about the professionals and agencies they worked with. Before selecting an adoption agency, women may wish to talk with them about their attitudes toward placing a child with a cancer survivor. Many agencies will be receptive toward this, but it’s important to know before making a final decision.
Egg Donation: Women who still have a uterus may be able to become pregnant using an egg donated by another woman. Through in vitro fertilization, the donated egg would be fertilized by the cancer survivor’s male partner or a sperm donor, and implanted in her uterus. Alternatively, another couple may donate a frozen embryo that could be implanted in her uterus.
Gestational Carrier or Surrogate: Women who do not have a uterus, or who are otherwise unable to sustain a pregnancy, may be able to have another woman carry a pregnancy for them. If the cancer survivor has functioning ovaries, her own egg can be fertilized by her male partner’s sperm and transferred to the uterus of another woman. In this case, the woman who carries the pregnancy is known as a gestational carrier. If the cancer survivor does not have functioning ovaries, another woman can both donate an egg and carry the pregnancy. This is the arrangement traditionally known as surrogacy.
Individual Decisions Within a Larger Community
The decisions that you make about building a family (or about coming to terms with not building a family) will be intensely personal, but know that you are part of a larger community of patients and healthcare providers who are grappling with these issues.
To think about future parenthood is to think about life after cancer. For many people with cancer, planning for the future may provide the motivation needed to get through treatment.
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