Benefits and Risks of PGD:

If you are considering using PGD, it is important to consider the benefits and the risks involved in the procedure.

Benefits:

• Currently, PGD is the only procedure that can provide you with information about carrier status before pregnancy.
• When successful, PGD ensures that your child will not inherit the BRCA mutation, thus ending the intergenerational transmission of that particular BRCA mutation.
• If you choose PGD, you will have the option to obtain additional genetic information (chromosomal abnormalities) that may influence you child’s health.

Risks of Undesired Outcome

Each embryo has a 50% chance of inheriting a BRCA mutation, assuming one biological parent carries the mutation. When you undergo Assisted Reproductive Technology (ART) to create embryos, it is possible that all embryos will inherit a mutation, that none will inherit a mutation, or (most likely) that some will and some will not inherit a mutation. The misdiagnosis rate for PGD in general ranges from 1-10% (Offit et al, 2006; Sermon et al. 2004). Because there are limited data on PGD for dominant genetic single gene mutations, like BRCA 1/2, mathematical modeling is used to predict PGD misdiagnosis in these instances, and it has been calculated to be as high as 11% (Lewis et al. 2001). You may also want to consider the success rate of Assisted Reproductive Technology (ART) using non-donor eggs that result in live births. For the last reported year, 2007, ART success was 30%, and multiple factors can contribute to this success, including maternal age (CDC, 2010). Therefore, it is likely that multiple cycles of ovarian stimulation and egg removal must be performed to become pregnant with a child free of BRCA mutation. IVF can be physically, financially, and emotionally demanding, and you may be limited in the number of cycles you can pursue.

• IVF may not produce any viable embryos
• Embryos collected in a given cycle may not be free of mutation
• Potential need for multiple IVF cycles
• Rare chance that PGD would fail to detect the gene mutation
• Embryos free of mutation may not result in successful pregnancy

Health Risks to Woman and Child

Female Hormones

If you have a history of cancer in your family, you may be concerned about hormone use. While hormones are generally considered safe, there are limited data available about the risk of IVF hormones as they relate to women with BRCA mutations. Additionally, fertility hormones have been known to cause a condition known as Ovarian Hyperstimulation Syndrome (OHSS) in which the ovaries produce too many eggs and become enlarged. According to the World Health Organization, .6-14% of women will experience mild to moderate symptoms including abdominal bloating, nausea, and chest pain. Rare cases, if left undetected or untreated can result in death in .2-1% of all cases (Kol, 2003). Also, multiple embryo transfer physically taxes the woman’s body.

Embryo Conditions and Transfer

During the course of IVF, embryos are cultured outside the body in a Petri dish and exposed to growth factors that may influence the child’s health and cognitive abilities later in life (Wilkins-Haug, 2009). The risk of accidental damage to an embryo during removal of cells for PGD testing is .6% (Hardy, et al. 1990). To increase the chances for pregnancy, often more than one embryo will be implanted. Higher order pregnancies can pose significant health risks to the developing fetus including premature birth, low birth weight, and an increase in birth defects. To reduce the risk of complications associated with higher order pregnancies, the American Society for Reproductive Medicine recommends that no more than two embryos transferred per IVF attempt.