How Many Embryos Do You Need Before Starting Surrogacy?
The short answer: you may need only one—if it's the right one
How many embryos do you need for surrogacy? Technically, just one. But it has to be the right embryo, and many other factors have to line up for a transfer to result in a healthy pregnancy.
When possible, it's better to have more than one transfer-ready embryo before you match, in case the first transfer isn't successful.
The number on paper matters less than what's behind it:
- Testing results. Whether each embryo has been tested with PGT-A, and what the result was
- Embryo quality. How each embryo was graded and developed in the lab
- Egg age at retrieval. The age of the eggs when they were retrieved, not the parent's age today
- Family goals. Whether you hope for more than one child, or have other specific goals
Your IVF physician is the best person to advise on your specific situation. Every case is different.
Why this question matters more in surrogacy
In surrogacy, your embryo plan sets the pace for everything after it. It affects when a match can move forward, how many transfers a surrogate may be asked to go through, and how your surrogacy agreement is written.
A small misread of an embryo report before matching can lead to a surrogate being medically prepared, then paused while another IVF cycle is completed. That's time and cost for you, and a disrupted plan for her.
Is "3 to 5 embryos" the right number for surrogacy?
Not necessarily. "3 to 5 frozen embryos" is a common industry rule of thumb, but it's a starting point, not a plan.
A count treats every embryo as equal. They aren't. Five untested embryos and one euploid, PGT-A tested embryo describe two very different starting points.
Following the rule by default can mean:
- Another IVF retrieval cycle before matching, even when a strong embryo is already in storage
- Months of added time before a surrogate can be matched
- Tens of thousands of dollars in added cost
That doesn't mean more embryos are never the right call. It means the decision should come from reading your embryo report, not from a blanket number.
What does an embryologist look for in an embryo report before matching?
An embryologist reads an embryo report for transfer readiness, not just quantity. The question is: how many of these embryos are realistic candidates for a successful transfer?
PGT-A results: euploid, "normal" or "correct"
Preimplantation Genetic Testing for Aneuploidy (PGT-A) screens embryos for an abnormal number of chromosomes. Depending on the testing platform, a passing result may be labeled euploid, normal or correct.
PGT-A tested embryos are often preferred in surrogacy cycles, because a euploid result helps identify embryos with a better chance of implanting and resulting in a healthy pregnancy.
The evidence is more nuanced than a simple rule. In its 2024 committee opinion, the American Society for Reproductive Medicine (ASRM) found PGT-A has not been shown to improve outcomes as a routine test for every IVF patient. The clearest per-transfer benefit was seen in women aged 35 to 40. Even so, Shane notes that most studies show transferring a euploid embryo reduces miscarriage caused by abnormal genetics, and that it may shorten the time to a successful pregnancy. PGT-A doesn't improve the pregnancy rate per egg retrieval.
Once an embryo has tested euploid, egg age at retrieval usually isn't a major factor in choosing it for transfer. Most euploid embryos have similar pregnancy rates, with some exceptions.
How an embryologist ranks embryos for transfer
- PGT-A result. Euploid (normal or correct) embryos are considered first
- Sex preference, if there is one. Where offered and requested, this comes before grade
- Embryo grade. How the embryo looked and developed during culture
- Day of freezing. Which day of development the blastocyst was frozen
Many factors go into embryo selection, but this is the general thought process. Storage location usually only matters when some embryos are held off-site and others are at the lab.
Why this matters before—not after—a match
Reading the report early lets everyone plan from the same facts. If a second retrieval is likely to be needed, it can happen before a surrogate is medically prepared, rather than in the middle of her preparation.
When should intended parents create more embryos before matching?
It makes sense to create more embryos before matching when your goals require more than one, or when your report doesn't yet include a strong transfer candidate. Common reasons:
- You hope to have more than one child through surrogacy. Each additional child needs additional embryos.
- You have a specific goal for sex selection. Where offered, this narrows which embryos are eligible for transfer. Policies vary by clinic: ASRM's 2022 ethics opinion leaves the decision to each clinic and advises against encouraging it for non-medical reasons.
- You have no PGT-A tested embryos, or none tested euploid. Your physician may recommend more cycles or testing first.
- Your physician recommends it. Your IVF doctor knows your history and is the best person to advise you.
If you already have at least one euploid embryo and your goal is one child, an additional IVF cycle before matching isn't always necessary.
Why team communication matters here
IVF and surrogacy aren't successful 100% of the time. Many variables need to line up for a successful transfer and, ultimately, a healthy baby.
That's why the embryo plan works best when your IVF clinic, agency, surrogate and you are on the same page before the match—not after a transfer doesn't go as planned.
Can you keep creating embryos after matching with a surrogate?
Yes. As long as you have at least one embryo available for transfer, you can continue creating embryos while working with your surrogate—or while she's pregnant.
This is one of the practical advantages of surrogacy for parents who hope for a sibling. Building your embryo bank doesn't have to hold up your first journey.
Planning a sibling journey with the same surrogate
If you hope to work with the same surrogate again, plan for a waiting period after delivery. Les Petits recommends waiting at least 6 months after a vaginal delivery and 12 months after a cesarean delivery before another transfer. Every woman is different, and her physician may recommend a different timeline based on her health history, pregnancy, delivery and recovery. Before any journey moves forward, Les Petits reviews the surrogate's medical records and requires clearance from her OBGYN, a Maternal-Fetal Medicine (MFM) specialist and a reproductive endocrinologist. Timing also depends on:
- Your IVF clinic's requirements
- Whether the delivery was vaginal or by cesarean section
For context, the American College of Obstetricians and Gynecologists (ACOG) and the Society for Maternal-Fetal Medicine advise avoiding pregnancy within 6 months of delivery, and counseling on the risks of a new pregnancy sooner than 18 months. After a cesarean, intervals under 18 to 24 months are linked to a higher risk of uterine rupture for those attempting a vaginal birth.
It's also worth talking about honestly up front: a sibling journey with the same surrogate isn't always possible. Timing, life circumstances or unforeseen complications can make a surrogate ineligible for a subsequent journey. Planning for that possibility early protects everyone's expectations.
Real example: how one embryo changed a family's timeline
One couple started their journey with one PGT-A tested, euploid embryo—fewer than the 3–5 embryos often recommended. They were willing to create more if the first transfer wasn't successful.
Following the industry-standard approach of banking 3–5 frozen embryos first would have meant more IVF before matching. For this couple, that could have added tens of thousands of dollars and 3–6 months to their timeline.
Instead, their IVF clinic, Les Petits, their surrogate and the parents agreed on a plan built around the embryo they had. That one embryo was all it took.
What made the difference
- Reading the report, not the count. Understanding that one euploid embryo was a realistic starting point
- A plan for "what if." Agreeing in advance on next steps if the transfer didn't succeed
- One shared picture. Clinic, agency, surrogate and parents working from the same information
Not every journey will look like this one. But it shows that additional IVF cycles aren't always required before entering a surrogacy agreement.
Why an embryologist on your surrogacy team can save months—and thousands
Few surrogacy agencies have an embryologist on the team to read embryo reports case by case, so the 3–5 embryo rule of thumb often fills the gap. Les Petits is led by Shane Zozula, BS, TS(ABB), an embryologist and IVF lab manager with more than 20 years of experience.
That changes what's possible for families who don't fit the typical profile.
When one strong embryo may be enough
If you have one embryo, but it's a good one, the right team may be able to build a plan around it. That plan pairs:
- An embryologist's read of your report. Understanding what your embryo's testing results and grade actually suggest, in partnership with your IVF physician
- Experienced journey management. Matching, preparation and transfer timing coordinated around the embryo you have
- A plan for "what if." Agreed next steps if the first transfer isn't successful, so there's no scramble later
The alternative is often another round of IVF just to reach the recommended count. For the family in the example above, that could have meant 3–6 more months and tens of thousands of dollars before matching.
Your family may not be typical—and that's fine
Rules of thumb are written for the average case. Your age at retrieval, your embryo results and your family goals may point to a different plan.
An agency that understands the lab can help you see whether the standard advice fits you, or whether a smaller, smarter starting point makes sense. Not every journey will work with one embryo. But no family should do more IVF than they need simply because the rule says so.
How Les Petits approaches embryo planning for surrogacy
Les Petits was shaped by embryology and the fertility clinic world, so embryo planning starts before the match, not after the first transfer.
- We read the embryo report with you. Testing results, grade and when each embryo was frozen—translated into what they mean for your timeline
- We ask your IVF physician the right questions early. So the plan reflects their medical guidance, not a rule of thumb
- We plan the "what if" before transfer. Next steps are agreed on in advance, so no one is left wondering
- We protect your surrogate's time. She isn't medically prepared for a transfer the embryo plan can't yet support
- We think ahead to siblings. Embryo goals, timing and the realities of a second journey are part of the first conversation
The little decisions made before a match—how a report is read, which question gets asked, who is told what—shape the time, cost and experience of everything that follows.
Sources
- American Society for Reproductive Medicine. The use of preimplantation genetic testing for aneuploidy: a committee opinion (2024)
- American Society for Reproductive Medicine. Recommendations for practices using gestational carriers: a committee opinion (2022)
- American Society for Reproductive Medicine. Use of reproductive technology for sex selection for nonmedical reasons: an Ethics Committee opinion (2022)
- American College of Obstetricians and Gynecologists and Society for Maternal-Fetal Medicine. Interpregnancy Care, Obstetric Care Consensus (2019)