CDC ART / NASS
Annual reporting covering every ART clinic in the US — the largest sample sizes, but the denominator is counted by egg-retrieval cycle and no confidence intervals are published.
Cross-border data, one yardstick
IVF success rates from around the world,
compared on the same yardstick
National IVF registries do not measure success the same way — some count by egg-retrieval cycles, some by transfer cycles, some include frozen embryo transfers, and the age bands differ. Compared side by side as-is, the conclusions are often wrong. We mark out the methodology behind every number, then put them next to each other.
Where the data comes from
We do not produce data; we normalise and verify it. The methodological differences between the three primary sources are the reason this site exists.
SART CORS
Maintained by the Society for Assisted Reproductive Technology, publishing live-birth rates by age band with confidence intervals. The underlying data is the same as the CDC's but processed differently — the two sets of numbers are not directly interchangeable.
HFEA
Bands by patient age rather than treatment cycle, and uses 'per embryo transfer cycle' as the denominator — a systematic difference from how the US registries count.
The full comparison of methodological differences (denominator definitions, age bands, whether cycles are cumulative, sample-size floors) is recorded in the database's registry
table and shown entry by entry on the site. See thedata source notes.
What you will find here
Fertility Clinics
Filter by country, service and cost range; every clinic's success rates carry their source and statistical methodology.
Doctors
Licences, affiliations and specialties, cross-indexed with the clinic data.
Success-rate dashboard
Side-by-side comparison on a stated common methodology, with sample sizes and confidence intervals; when methodologies do not match, it says so explicitly.
Calculators
Success rates, costs, egg-freezing planning and more. Every coefficient names its source and its derivation.
How we work
01
No source, no data
Every success-rate entry must carry a working link to its original source. Entries whose sources are dead or unverifiable are held for verification and never reach the dashboard.
02
Methodology, stated in full
Egg-retrieval or transfer cycles, cumulative or not, how ages are banded, how large the sample is — if any one of these is missing, the entry does not get shown.
03
No rankings, no paid placement
This site does not rank clinics by success rate or accept paid placements. The display-order rules are published on theAbout us.