How to Choose an IVF Clinic Using Success Rates — Without Being Misled by Them

If you've started researching IVF clinics, you've probably landed on a page of success rate numbers and wondered what you're actually looking at. Here's the thing: both SART (the professional body that tracks U.S. fertility clinic data) and the CDC say directly: comparing clinics purely by their headline success rate isn't a scientifically valid way to choose one. That's not because the data is fake — it's because the number alone doesn't tell you what you need to know.

Why the Same Number Can Mean Different Things

Two clinics can report very different success rates without either one being "better" at IVF. A clinic that primarily treats patients using donor eggs, or works with an older or more medically complex patient population, will naturally report different outcomes than a clinic that mostly treats younger patients with straightforward diagnoses. The rate reflects who walked through the door as much as it reflects the clinic's skill.

There's also a more subtle factor: how a clinic handles cycle cancellations. Some clinics report data to the CDC only, which is mandatory; others also report voluntarily to SART, a more detailed registry. Research comparing these two groups have found that cancellation gets reported more consistently — and more often — among clinics that report to both, which affects how their overall numbers look on paper. A clinic that cancels more cycles before they count against a "failure" can end up with rates that look better without necessarily reflecting better outcomes for the patients who walked in the door.

What to Actually Look At

• Age-banded rates, not the headline number. Success rates are reported by age group for a reason — your outlook at 32 and 42 are different conversations. Look at the band that applies to you.
• Live birth rate, not just pregnancy rate. A pregnancy that doesn't result in a live birth is counted differently across sources — make sure you know which number you're reading.
• Per-cycle-start vs. per-transfer rates. A rate calculated only from patients who made it to transfer looks different from one that includes everyone who started a cycle, including those who never got there.
• Cancellation and "freeze-all" policies. Ask how the clinic decides when to cancel a cycle or convert to a freeze-all approach, since this directly shapes their reported numbers.

Questions Worth Asking a Clinic Directly

• What does your success rate look like specifically for my age group and diagnosis?
• How do you decide when to cancel a cycle, and how does that factor into your reported numbers?
• What percentage of your patients need donor eggs, and are they included in the overall rate I'm looking at?

Frequently Asked Questions

Is a higher success rate always a better clinic? Not necessarily. Differences in patient population, diagnosis mix, and reporting practices can all shift a clinic's numbers without reflecting a real difference in care quality.

What's the difference between SART and CDC reporting? The CDC collects data from all U.S. clinics as required by federal law. SART is a voluntary professional registry that many, but not all, clinics also report to, often with more detailed breakdowns.

Should I ignore success rates altogether? No — they're useful when read correctly, especially age-banded and diagnosis-specific data. The mistake is comparing one clinic's headline number to another's without context.

Why do some clinics have lower cancellation rates than others? It can reflect different clinical philosophies about when to proceed with a cycle versus cancel it — worth asking about directly rather than assuming a lower cancellation rate means a stronger clinic.

Talk to a Fertility Specialist

Success rates are a starting point for research, not a final answer. Ask any clinic you're considering to walk you through their numbers for someone in your specific situation, not just their overall average.

This article is for general informational purposes and isn't a substitute for personalized medical advice. Talk to your fertility specialist about your specific situation before making treatment decisions.