For infertility patients, an IVF cycle can feel like a numbers game. How many follicles are developing well? How many oocytes are retrieved? How many will fertilize? And most important, how many embryos will be ready to transfer into the womb? Although many people say “it only takes one,” I have found that most people going through in vitro fertilization (IVF) are hoping for several.

Why do people hope for several embryos?

If it only takes one, why hope for more? For those struggling with infertility, safety in numbers may feel heartening. Some families hope to have more than one child, and welcome the chance to freeze embryos for future use. They hope to avoid the costs, both financial and emotional, of undergoing another IVF cycle. And for those who worry about aging eggs, creating embryos now enables them to use the mom’s eggs before she gets any older. Extra embryos also provide peace of mind should the cycle not result in pregnancy or end in miscarriage.

What questions arise when extra embryos exist?

In many ways, having several embryos cryopreserved is a good thing. I know one couple with five children, all from one egg donor cycle. For this couple, the bounty of embryos was a gift that kept on giving. However, for others, extra embryos can be problematic. Here are a few examples of the downside of cryopreserving embryos.

• Cryopreserved embryos can offer false hope. Reproduction is truly a mystery. I know a couple who have two sons through egg donation. They conceived their first son on their first donor cycle, a cycle that yielded 12 frozen embryos. All went so smoothly the first time around, the couple assumed that they would have another pregnancy after at most three frozen transfers. As it turned out, they went through all 12 embryos before moving on to another donor. The first cycle with their new donor brought them their second son.
• Parents may question family size. Some people embark on parenthood with a clear idea of how many children they want. Others want to take it as it comes, deciding after the birth of each child whether their family feels complete. Either way, they feel that the decision is theirs; they don’t have to have more children than they are prepared to parent.

  Ironically, this assumed ability to limit the size of one’s family is challenged when IVF yields “extra” embryos. Some feel a responsibility to the embryos to give them a chance at life after all they went through to create them. Or they may wonder if a larger family is meant to be. Some fear that not using the embryos demonstrates a lack of gratitude. After all, they would have done most anything to become parents. Can they really turn away from this ultimate gift?

What choices do people make?

What do families do when they have embryos cryopreserved that they do not intend to use? I have found that many people deal with this with avoidance. Each year they pay a storage fee and give themselves a pass to avoid the topic for another year. Some regard their embryos as a kind of fertility insurance policy. The embryos are there should they need them.

For some families, however, the decision cannot be passive. Some parents feel it is important to acknowledge that their family is complete. They prefer to actively confront the question of what to do with their extra embryos. For some this decision is fairly straightforward: they see an embryo as having a potential for life but as not yet being a life. They may decide to dispose of extra embryos and feel comfortable with their choice.

Not so for everyone. Some parents look at the child or children they have from IVF and want to give the embryos life. They may identify with birth parents in adoption, feeling a need to find parents for their embryos. Others choose to donate extra embryos to science, feeling that this raises fewer social and ethical issues, and offers them — and their embryos — the opportunity to help other infertile families through research.

When embarking on an IVF cycle, infertile individuals and couples understandably hope for several embryos. For some this proves a blessing: they are able to have a longed-for child or children. Yet many also learn that infertility is a complex experience that does not end with the birth of their children. Having cryopreserved embryos is but one way in which infertility remains with people long after their families are completed.