If you’ve tested positive for a mutation in the BRCA1 or BRCA2 gene — or some other inherited gene mutation associated with increased risk of breast cancer and possibly other cancers — it’s natural to be concerned about passing the mutation along to your biological children. There’s a 50% chance that any child you have will inherit the mutation. The same holds true if you are not a mutation carrier but your partner is.
Some women of childbearing age are now choosing to use preimplantation genetic diagnosis, or PGD, to ensure they won’t pass a BRCA1 or BRCA2 mutation on to their children. (PGD also can be used in cases of other cancer-related mutations. On this page, we’ll just refer to BRCA1 and BRCA2, since these are the most common genes linked to breast cancer risk.) For several years, couples have used PGD to avoid passing along hereditary diseases such as cystic fibrosis, muscular dystrophy, and Huntington’s disease. But now, some parents are using it to avoid passing along the BRCA1 or BRCA2 mutation.
PGD can offer parents (and their future children) peace of mind, but it does involve a lot of time, effort, and expense. The first step is going through the process called in-vitro fertilization, or IVF.
You may know about IVF as a fertility treatment. With IVF, a woman takes medications to stimulate her ovaries to produce multiple eggs. The eggs are removed and fertilized outside the body in a test tube. Successfully fertilized eggs then become embryos.
After a few days, PGD can be performed: One or two cells can be removed from each embryo and tested for the particular BRCA1 or BRCA2 mutation carried by the parent. In addition, the embryo can be screened for chromosomal disorders such as Down syndrome and Turner syndrome, which are not inherited but instead caused by changes in the number of chromosomes. The couple or mother can then choose only healthy, BRCA-mutation-free embryos to be implanted in the uterus and/or stored for future use.
IVF isn’t always successful, though: Sometimes no embryos form, or those that do could all test positive for the mutation. Once an embryo or embryos are placed into the uterus, they don’t always result in pregnancy. So multiple cycles of IVF and PGD may be needed over time. Costs for IVF and PGD can range widely, from $10,000 to $20,000 per cycle. Although health insurance plans may offer some coverage in selected cases, the costs of multiple cycles can add up quickly.
If you’re considering PGD, talk to your genetic counselor and a fertility specialist. They can help you weigh the pros and cons of your situation. Some women find that they need to have IVF anyway — either because they are having trouble getting pregnant, or they are “banking” eggs or embryos to use after their cancer treatments. In these cases, adding PGD for the BRCA1 or BRCA2 mutation makes sense. Other women decide they want to have PGD no matter what because they don’t want their children to face the same worries about cancer risk that they did. Still others feel that, while they’re concerned about their future children’s health, PGD is simply not worth it or out of reach financially. They are encouraged by the fact that there’s a 50-50 chance that any child will not inherit the mutation.
PGD for BRCA mutations is controversial for a number of reasons, such as:
- A BRCA mutation is not itself a disease, but a risk factor for an adult-onset cancer, and there are ways that mutation carriers can greatly lower their risk later in life.
- Selecting mutation-free embryos isn’t a guarantee that a child will never develop cancer or other serious diseases in his or her lifetime.
- Some people have ethical concerns about destroying embryos because they carry a genetic mutation. They also worry about parents selecting for other traits such as gender.
- We're not yet sure whether the hormonal medications given to stimulate the ovaries to produce eggs for IVF could pose a greater risk to women who are BRCA1 or BRCA2 mutation carriers. Research is ongoing.
This truly is a personal decision to be made in collaboration with your healthcare team, partner, and family members.