Live Birth Rate
Last updated: March 2026
What is live birth rate?
Live birth rate measures the percentage of IVF cycles that result in an actual baby delivered alive. It is the most meaningful success metric, unlike pregnancy rate (a positive test, which includes biochemical losses) or clinical pregnancy rate (ultrasound-confirmed heartbeat). Birth rates are “typically three percentage points lower than pregnancy rates” (HFEA, 2021).
HFEA 2021 fresh transfer data
| Age | Pregnancy rate | Live birth rate | Gap |
|---|---|---|---|
| 18–34 | 41% | 33% | 8pp |
| 35–37 | 33% | 25% | 8pp |
| 38–39 | 25% | 17% | 8pp |
| 40–42 | 16% | 10% | 6pp |
| 43–50 | 6% | 4% | 2pp |
(HFEA, 2021)
Cumulative rates: why one cycle isn’t the whole picture
A single IVF cycle gives you one shot. But most patients need multiple cycles. HFEA registry data from 178,898 women showed a cumulative live birth rate of 42.3% after 3 complete cycles (conservative estimate) and 65.3% after 6 cycles (McLernon et al., PMC4934614). The optimal estimate, adjusting for patients who dropped out for non-medical reasons, reached 57.1% after 3 cycles and 82.4% after 8 (Smith et al., Human Reproduction, 2016).
These numbers are encouraging if you can afford multiple attempts. That’s the real constraint for most patients travelling abroad for treatment.
Fresh vs frozen
HFEA data shows frozen embryo transfer birth rates are now comparable to fresh transfer rates across age groups, thanks to improvements in vitrification. In 2021, 43% of all UK embryo transfers were frozen (HFEA, 2021). Some studies suggest frozen transfers carry lower risks of preterm birth and low birth weight compared to fresh (Maheshwari et al., Human Reproduction Update, 2018). When comparing clinics, ask whether their reported rates include or exclude frozen transfers.
How clinics game the numbers
Clinics sometimes advertise pregnancy rates rather than live birth rates. A “50% success rate” could mean 50% pregnancy rate (positive test), which drops to roughly 42% clinical pregnancy (ultrasound-confirmed heartbeat), which drops further to about 37% live birth. Same clinic, same patients, three different numbers.
Other ways to inflate stats: reporting per-transfer rates instead of per-cycle-started (which hides cancelled cycles), cherry-picking younger patients, or excluding difficult cases. HFEA publishes verified clinic-level data. ESHRE collects comparable European data. If a clinic won’t tell you their live birth rate per cycle started, for your specific age group, that’s a red flag.
What to ask your clinic
- What is your live birth rate per embryo transfer for my age group?
- Is that per cycle started or per transfer? (Per transfer is always higher because cancelled cycles disappear.)
- Are these rates for fresh, frozen, or combined transfers?
- Do your reported rates include PGT-A-screened cycles?
- What is your live birth rate with donor eggs vs own eggs?
Want to compare clinic outcomes? Get a personalised quote or use our calculator.
Sources
- HFEA. Fertility Treatment 2021: Preliminary Trends and Figures: https://www.hfea.gov.uk/about-us/publications/research-and-data/fertility-treatment-2021-preliminary-trends-and-figures/
- Maheshwari et al. Is Frozen Embryo Transfer Better for Mothers and Babies? Human Reproduction Update, 2018.
- McLernon et al. Cumulative live birth rates after one or more complete cycles of IVF. Human Reproduction, 2016: https://pmc.ncbi.nlm.nih.gov/articles/PMC4934614/
- Smith et al. Live birth rates after assisted reproduction. Human Reproduction, 2016: https://pubmed.ncbi.nlm.nih.gov/26783243/
This page is for informational purposes only and does not constitute medical advice. Always consult a qualified fertility specialist before making treatment decisions.