How to Read a Fertility Clinic’s Success Rates

Success rates are one of the first things people search for when comparing fertility clinics, and one of the hardest things to actually understand. The numbers come from a real, regulated reporting system, but a single percentage can’t capture the full picture on its own. This guide breaks down what the data actually means and what to look at beyond the headline number.

What is SART?

SART stands for the Society for Assisted Reproductive Technology. It’s the professional organization that sets reporting standards for fertility clinics in the United States and collects outcome data from its member clinics every year. Most clinics performing IVF in the US report to SART, and that data is reviewed against the same definitions and formulas, so patients can compare clinics using a shared standard rather than each clinic’s own marketing language.

Why do clinics report their outcomes to SART?

Reporting is part of what it means to be a SART member clinic. It gives patients a transparent, standardized way to see how a clinic’s outcomes compare to national data, and it gives the fertility field a way to track trends and improve care over time. A clinic’s SART membership is worth checking on its own, since it signals the practice has agreed to this level of outside reporting and oversight.

What exactly is a live birth rate?

A live birth rate is the percentage of treatment cycles that resulted in the birth of a living baby, as opposed to a positive pregnancy test or an early miscarriage. SART tracks it in a few different ways, most often as the live birth rate per intended egg retrieval and the cumulative live birth rate, which counts all embryo transfers from a single retrieval, fresh and frozen. Live birth rate is generally considered the most meaningful number to look at, since pregnancy rates and implantation rates can look encouraging without reflecting how many patients actually go home with a baby.

What’s a good live birth rate?

There isn’t one universal number that counts as good, because live birth rates depend heavily on age and diagnosis, not just on the clinic. National SART data generally shows the highest live birth rates per retrieval in patients under 35, a gradual decline through the late 30s, and a more significant drop after 40. A rate that looks modest for a clinic treating a lot of complex or older patients can still reflect excellent care. The most useful way to read the number is in the context of your own age and fertility history, ideally with your doctor walking you through it.

Why do success rates vary so much by age?

Age affects egg quantity and egg quality more than almost any other factor in fertility treatment, and that shows up directly in the data. A clinic isn’t choosing to have lower success rates for older patients. It’s reporting the biological reality of what egg retrieval and embryo development look like at different ages. This is also why it rarely makes sense to compare your own odds to a clinic’s overall average rather than the rate for patients closer to your age and diagnosis.

Can I compare two clinics side by side?

You can, but carefully. Two clinics can report very different numbers for reasons that have nothing to do with quality of care, including how selective they are about which patients they accept for treatment, how many total cycles they perform each year, and which specific metric is being highlighted. A clinic with fewer annual cycles can also show more year-to-year swing in its percentages simply because the sample size is smaller. Reading two reports from the same reporting year, using the same metric, is the fairest way to compare.

What should I look at beyond the headline number?

A few things round out the picture. The cumulative live birth rate tells you the chance of success across a full retrieval and all resulting embryos, not just the first transfer. The multiple birth rate and single embryo transfer rate speak to how a clinic balances success with patient safety. Lab accreditation and physician board certification are worth confirming independently. None of these show up in a single percentage, but together they say more about a clinic’s approach than one number ever could.

Does a lower number always mean a lower quality clinic?

No, and this is one of the most misunderstood parts of reading SART data. Clinics that specialize in complex cases, take on patients other practices have turned away, or are newer and still building patient volume can show lower or more variable numbers without that reflecting the quality of care a patient receives. The number alone doesn’t tell you that story. The context behind it does.

What if a clinic doesn’t publish detailed success rates?

Not every practice has a large, publicly reported dataset, especially smaller or newer clinics still building patient volume. That doesn’t necessarily mean a clinic is hiding something. SART’s reporting depends on data volume and consistency, so it’s worth asking a clinic directly about its SART membership and current reporting status rather than assuming the absence of a public report says anything on its own.

Where can I look up SART data myself?

SART’s own database lets you search any member clinic by name and location and view its reported outcomes by year and age group, alongside the national summary report for comparison. It’s worth reading the data directly at sartcorsonline.com rather than relying only on how a clinic describes its own numbers.

Should success rates be the only factor in choosing a clinic?

Success rates matter, but they’re one part of a bigger picture that includes how a clinic communicates, how personalized your treatment plan feels, and how supported you feel throughout a process that can be physically and emotionally demanding. Many patients weigh clinic culture and communication just as heavily as the published numbers, especially when the numbers themselves need this much context to interpret well.

How does RSC Fertility think about success rates?

RSC Fertility reports outcomes as a SART member clinic, using the same standardized definitions covered above. As a newer, growing practice, we believe the most useful conversation about your own odds happens directly with your doctor, in the context of your age, diagnosis, and treatment history, rather than through a single published number. If you’d like to talk through what success could look like for you, our team is glad to walk through it during a consultation.

How can PGT affect the way success rates look?

Preimplantation genetic testing (PGT), particularly PGT-A, is another important factor to consider when comparing clinics. Clinics that use PGT-A in a large proportion of IVF cycles may have a different mix of patients and transfer strategies than clinics that use it less often. Because embryos may be biopsied, frozen, and transferred later—and because transfer outcomes may be reported after the current reporting period—the resulting success-rate profile may not be directly comparable with that of a clinic using a different testing strategy. This does not make the data less valid; it means the data should be interpreted in the context of how the clinic practices.