Two people can read the same IVF success rate and walk away with opposite conclusions. The word “success” can describe a positive pregnancy test, a confirmed pregnancy, or a baby, and each report decides which one to count.
Once you know which outcome a number counts and how the count was built, success rate data gets much easier to read. At InVia Fertility, we want you to feel confident reading these numbers, and our own published results are a great place to practice.
How IVF Success Rates Are Measured
When a clinic advertises a 50% success rate, the natural assumption is that half of everyone who starts treatment brings home a baby. Depending on the source, “success” can mean a positive pregnancy test, a confirmed clinical pregnancy, or a live birth, and those three outcomes can differ widely from one another.
Live birth is the outcome to anchor to when you compare numbers, since a baby is the goal. The Society for Assisted Reproductive Technology (SART) reports birth outcome data from its member clinics, giving you a consistent way to look at assisted reproductive technology (ART) results.
InVia Fertility has served the Chicago area since 2002, so the results we publish reflect an established program with a long, steady track record.
Understanding the IVF Live Birth Rate
Two clinics can each report a 55% success rate while one counts positive pregnancy tests and the other counts live births. Our SART report measures success as live births per intended egg retrieval. In 2023, our live birth rate for people under 35 using their own eggs was approximately 46.9% per intended egg retrieval, counting all embryo transfers.
An intended retrieval counts from the moment a cycle begins, whether or not that cycle reaches an embryo transfer. Counting every started cycle gives you a fuller and more honest picture than counting only the cycles that made it to transfer.
Why IVF Success Rates by Clinic Can’t Be Compared Side by Side
Lining up two clinics’ numbers and choosing the higher one is a natural instinct. The Centers for Disease Control and Prevention (CDC) cautions that comparing success rates across clinics may not be meaningful, because clinics care for different groups of people and use different treatment methods.
A program that welcomes people with more complex medical histories and needs, including people who have had unsuccessful cycles elsewhere, will show lower raw numbers than a program that only treats straightforward cases, even when both programs deliver excellent care.
How Clinic Selection Practices Can Inflate Success Rates
A clinic can raise its published rate simply by being selective about who it treats. SART’s own clinic report notes that differences in who a clinic selects for treatment can inflate or lower a clinic’s rates, and none of that selection shows up in the percentage itself.
Asking a clinic how it approaches complex cases will tell you more than the percentage alone. A program that welcomes difficult diagnoses is showing confidence in its care, and that confidence is a good sign as you choose your care team.
Understanding IVF Success Rate by Age
Age is one of the key factors in IVF success, and SART reports own-egg results by age group. Our 2023 SART report shows these live birth rates per intended egg retrieval, using a person’s own eggs and counting all embryo transfers:
- Under 35, approximately 46.9%
- 35 to 37, approximately 40.3%
- 38 to 40, approximately 24.6%
- 41 to 42, approximately 8.2%
Births from a retrieval cycle may not happen until up to two years after the cycle starts, so SART labels each year’s report preliminary until those outcomes are complete and final once they are. The 2023 report is our most recent final report.
A comparison of clinic success rates may not be personally applicable because patient medical characteristics, treatment approaches, and entry criteria for ART may vary from clinic to clinic.
Your specialist will walk through what these numbers mean for your own situation, alongside everything else that shapes an individual outcome.
Own-Egg and Donor-Egg Success Rates Are Reported Separately
Own-egg cycles and donor-egg cycles are reported as separate data sets, and averaging them together would be misleading. The CDC does not break out donor-egg results by age group, since an intended parent’s age does not substantially affect success when using donor eggs. InVia Fertility offers both paths, and each has its own data reflecting a different starting point.
How IVF Statistics Count Cycles
Every success rate is a fraction, and the bottom half of that fraction shapes what the top half means. The CDC shows own-egg success rates three ways, per intended retrieval, per actual retrieval, and per transfer, and each choice produces a different number from the same outcomes. Intended retrieval is the broadest and most transparent choice, since it includes every cycle that started, even cycles that never reached an embryo transfer.
Single-transfer and cumulative rates measure different things too. SART’s clinic report shows the outcome of the first embryo transfer separately from the cumulative outcome, which counts a live birth from any fresh or frozen transfer that follows the same egg retrieval. Cumulative rates run higher because they capture the full result of one retrieval across every transfer that follows.
Fresh vs. Frozen Embryo Transfer Success Rates
A multicenter study of more than 8,000 first embryo transfers found comparable live birth rates between fresh transfers and frozen embryo transfers (FET) after freezing all embryos, across every age group studied.
Whether a fresh or frozen transfer suits your plan is a question your care team will help you answer based on your specific protocol.
How to Read Fertility Clinic Success Rates on InVia Fertility’s SART Report
Our full SART report is available on SART’s public reporting site. As you read the report, look for these sections:
- results for your own eggs and for donor eggs, shown on separate tabs
- live births per intended egg retrieval, counting all embryo transfers
- live births from the first embryo transfer alone
- the reporting year and whether that year’s report is final or preliminary
Bring our SART results to your first visit along with your questions. Our team will walk through what the numbers are likely to mean for you based on your full history.
Reading success rates can feel like learning a new language, and you don’t have to become fluent on your own. We’re here to help you make sense of the numbers and support you every step of the way as you build your family.
Bring Your Questions, and We’ll Bring the Context
A specialist at InVia Fertility will sit down with you, walk through what these numbers mean for your situation, and answer every question that came up while you were reading.
Schedule an appointment at InVia Fertility whenever you’re ready.
