IVF success rates are among the most misused numbers in reproductive medicine — the same “60%” can mean something 20 percentage points different depending on which statistic a clinic reports. This guide breaks down live birth rates by age (45–50% under 35, under 10% over 42), by technology, and by country using five public registries: SART (USA), HFEA (UK), ESHRE (Europe), ANZARD (Australia/NZ), and JSOG (Japan) — every table cites its source, and every conclusion is backed by data, not marketing.
Which IVF Success Number Actually Matters?
Live birth rate (LBR) is the only metric that answers the question patients really have: how often does treatment end with a baby? Before comparing any clinic’s numbers, identify which of six measurement conventions is being used.
Clinical Pregnancy Rate
Clinical pregnancy rate counts cycles with an ultrasound-confirmed gestational sac and fetal heartbeat, divided by transfer cycles. Typical values run 45–55% under 35 and 15–25% over 40 — and it sits 10–15 points above live birth rate, because biochemical pregnancies and early miscarriages are included.
A clinical pregnancy is not a baby, so treat this number as secondary.
Live Birth Rate
Live birth rate counts cycles resulting in at least one live-born baby, and it is the single most important metric in fertility treatment. HFEA, SART, and ESHRE all report LBR as their headline outcome.
When evaluating any clinic, compare LBR first and ignore everything else.
Single-Cycle vs. Cumulative Success Rate
A single-cycle rate covers one egg retrieval plus transfers from that one cohort of embryos; a cumulative rate merges outcomes across multiple transfers — or even multiple cycles — from the same patient. Under 35, single-cycle live birth is about 50%, but cumulative success across 3 cycles reaches 80%+, because younger patients retrieve more embryos per cycle.
The cumulative advantage shrinks for older patients with fewer eggs.
Per Transfer vs. Per Cycle Started
Per-transfer rates are the most manipulable metric in IVF reporting. Per transfer excludes cancelled cycles (OHSS, thin lining, no viable embryos), so it typically inflates results by 10–20 points, while per cycle started counts every stimulated cycle and reflects the real odds from injection to delivery.
SART publishes both — prioritize per cycle started.
Fresh vs. Frozen Embryo Transfer
The dominant global trend is “freeze-all” with a deferred frozen embryo transfer. FET live birth rates now match or exceed fresh transfers in most age groups.
The mechanism: the high-estrogen environment of a fresh stimulation cycle can impair implantation, while a programmed or natural FET cycle offers a more physiological endometrium. Detailed comparison tables appear below.
Euploid Transfer Rate — Post-PGT-A
After PGT-A screening confirms a chromosomally normal (euploid) embryo, live birth rate becomes far less age-dependent. A euploid embryo from a 42-year-old carries a 50–60% live birth chance — comparable to an unscreened embryo at age 30.
This figure represents the ceiling after embryo selection, not the average outcome of an untested cycle.
What Are IVF Success Rates by Age?
The table below synthesizes the SART 2023 National Summary Report and the HFEA 2022 Fertility Treatment Report for patients using their own eggs. Individual clinics can deviate 10–15 points from these national averages depending on their patient mix.
Single-Cycle Live Birth Rate by Age Group
| Age Group | LBR per Cycle Started | LBR per Transfer† | Cumulative LBR (3 cycles) |
|---|---|---|---|
| Under 35 | 45–50% | 44–47% | 75–85% |
| 35–37 | 35–40% | 35–39% | 60–70% |
| 38–40 | 20–30% | 24–30% | 45–55% |
| 41–42 | 10–18% | 13–19% | 25–35% |
| Over 42 | 5–10% | 7–10% | 15–20% |
Sources: SART 2023 National Summary, HFEA Fertility Treatment 2022
† The “LBR per Transfer” column is a derived estimate. SART does not publish this denominator; the column is calculated from SART’s first-embryo-transfer per-retrieval figures divided by the share of cycles that reach a transfer, and cross-checked against HFEA 2022 live birth per embryo transferred (42% under 35) and ESHRE per-transfer rates (38–42%). See the denominator note below.
Denominator note (important): the two rate columns have different denominators — “LBR per Cycle Started” divides by retrieval cycles started, while “LBR per Transfer” divides by transfers actually performed (excluding cancelled cycles and cycles with no transferable embryo). They cannot be subtracted or swapped.
More importantly, the SART 2023 snapshot report publishes no “LBR per Transfer” row at all. It has only two denominators — per intended egg retrieval and per thaw — across four raw rows: per intended egg retrieval (all embryo transfers) 53.2% under 35, 39.9% at 35–37, 26.2% at 38–40, 13.2% at 41–42 and 4.1% over 42; per intended egg retrieval (first embryo transfer) 39.4%, 31.0%, 21.3%, 11.3% and 3.7%; per thaw (second embryo transfer) 46.6%, 44.9%, 40.7%, 32.1% and 20.2%; per thaw (additional transfers/long-term freezes) 48.9%, 48.0%, 46.8%, 43.0% and 36.6%. Before quoting any figure, check whether its denominator is a cycle or a thaw — calling 46.6% a per-cycle rate is a common error; it is per thaw.
Three insights drive this data. First, 35 is a clear inflection point: rates drop about 10 points at 35–37, another 10 points at 38–40, then fall off a cliff after 40.
Second, cumulative 3-cycle success is 1.5–2× the single-cycle rate, with the largest gains under 38 where each retrieval yields multiple usable embryos. Third, own-egg live birth after 42 stays below 10% — a signal that donor eggs or PGT-A with euploid transfer may deserve the budget instead. For a full age-by-age breakdown see our IVF success rate by age guide.
How Much Do PGT-A, ICSI, and Frozen Embryos Improve Success?
PGT-A delivers the largest per-transfer gain of any add-on — up to 35–40 percentage points for patients over 41 — while ICSI only helps when male factor infertility is present. Add-ons should be matched to specific indications, not stacked.
PGT-A Screening and Euploid Transfer
PGT-A strips chromosomal abnormality — the factor age cannot be argued with — out of the transfer decision, so only euploid embryos are placed. The figures below combine multiple SART center reports and published data from leading centers such as CCRM and Columbia:
| Age Group | LBR per Transfer Without PGT-A | LBR per Euploid Transfer With PGT-A | Gain |
|---|---|---|---|
| Under 35 | 50% | 60–65% | +10–15% |
| 35–37 | 38% | 58–63% | +20–25% |
| 38–40 | 25% | 55–60% | +30–35% |
| 41–42 | 14% | 50–55% | +35–40% |
| Over 42 | 8% | 45–50% | +37–42% |
The older the patient, the bigger the PGT-A benefit. By 38–40, 60–80% of oocytes are aneuploid, so unscreened transfer is effectively a blind draw.
This is the core reason PGT-A is strongly recommended for advanced maternal age. See our advanced maternal age IVF guide for the full clinical case.
First Transfer vs. Later Frozen Transfers
The SART 2023 national summary does not split by “fresh vs. frozen” — it reports by transfer sequence. Later transfers actually show a higher live birth rate per attempt:
| Age Group | First Transfer LBR (per retrieval) | Second Transfer (per thaw) | Later Transfers (per thaw, long-term storage) |
|---|---|---|---|
| Under 35 | 39.4% | 46.6% | 48.9% |
| 35–37 | 31.0% | 44.9% | 48.0% |
| 38–40 | 21.3% | 40.7% | 46.8% |
| 41–42 | 11.3% | 32.1% | 43.0% |
| Over 42 | 3.7% | 20.2% | 36.6% |
This ordering should not be read as “frozen beats fresh.” The first-transfer column covers every first transfer in a retrieval cycle (including fresh transfers), while the second and third columns are all frozen-thawed transfers — different denominators, so they cannot be subtracted from one another. Three mechanisms explain the higher rates later in the sequence: frozen transfer allows PGT-A to screen out aneuploid embryos first; a thaw cycle avoids the high-estradiol environment of stimulation, which can compromise endometrial receptivity; and a freeze-all strategy lets the clinician pick the cycle with the best endometrium. The gap is widest over 42, where a later transfer reaches 36.6% versus 3.7% for a first transfer — close to 10×. That is why freeze-all plus PGT-A is favoured at advanced maternal age.
ICSI vs. Conventional IVF
ICSI (intracytoplasmic sperm injection) solves fertilization failure, not implantation failure. In severe male factor cases — low count, poor motility, abnormal morphology, high DNA fragmentation — ICSI lifts fertilization from 30–40% to 65–80%.
For non-male-factor infertility there is no significant difference: a multi-center RCT (ESHRE 2018) found live birth rates of 33% with conventional IVF versus 32% with ICSI. ICSI is not “the better, more expensive option” — it is the right option only for its indication.
Assisted Hatching, EmbryoGlue, and Other Add-Ons
Assisted hatching uses a laser or acid opening in the zona pellucida to help the embryo hatch, but meta-analyses show no significant live birth benefit for the general population — at best it may help with recurrent implantation failure or frozen-thawed embryos.
EmbryoGlue (a hyaluronan-enriched transfer medium) shows a small implantation gain of roughly 5% in some studies, at low evidence grade. Do not stack add-ons without a specific indication.
How Do IVF Success Rates Compare by Country?
Cross-country comparison is only directional: the US SART reports per retrieval, UK HFEA reports per embryo transfer, and Japan’s JSOG averages are dragged down by a very high share of older patients. Treat the tables below as reference points, not a leaderboard.
United States — SART 2023 National Data
The SART national summary reports per intended egg retrieval — all transfers after a single retrieval (including later thawed transfers) are pooled into one figure, which is why these numbers sit above a per-transfer rate:
| Age Group | LBR per Retrieval (all transfers) | of which singleton LBR | Cycle starts |
|---|---|---|---|
| Under 35 | 53.2% | 51.5% | 57,602 |
| 35–37 | 39.9% | 38.9% | 38,895 |
| 38–40 | 26.2% | 25.4% | 37,878 |
| 41–42 | 13.2% | 12.8% | 19,367 |
| Over 42 | 4.1% | 4.0% | 13,989 |
SART captures roughly 90% of all US ART cycles, making it the most transparent and most finely age-stratified registry anywhere. Top US centers typically run 10–15 points above the national average — Columbia University Fertility Center’s SART 2023 data, for example, shows a 66% under-35 FET live birth rate.
United Kingdom — HFEA 2022 Data
| Age Group | LBR per Embryo Transfer |
|---|---|
| Under 35 | 42% |
| 35–37 | 34% |
| 38–39 | 24% |
| 40–42 | 13% |
| 43–44 | 5% |
| Over 44 | 2% |
Source: HFEA Fertility Treatment 2022
HFEA applies the strictest methodology of any registry: rates are calculated per embryo transfer — so a failed single transfer is never diluted by multi-embryo cycles — and every cycle is included. UK law obliges every licensed clinic to submit complete data, which eliminates selective reporting.
Europe — ESHRE EIM 2020–2021 Data
| Age Group | IVF/ICSI LBR per Transfer |
|---|---|
| Under 35 | 38–42% |
| 35–39 | 28–32% |
| 40–44 | 12–16% |
| Over 44 | 4–6% |
Performance inside Europe is uneven: Spain, the Nordics, and Czechia beat the continental average, while parts of Eastern and Southern Europe fall below it. ESHRE’s structural limitation is that member countries still differ in reporting completeness and statistical conventions.
Asia’s Major Markets
Japan runs one of the world’s largest single ART markets, with more than 500,000 cycles per year. JSOG 2022 data:
| Age Group | Fresh Embryo LBR | FET LBR |
|---|---|---|
| Under 35 | 50% | 54% |
| 35–37 | 40% | 45% |
| 38–40 | 28% | 32% |
| Over 40 | 12% | 14% |
Source: Japan Society of Obstetrics and Gynecology ART Databook 2022
Japan’s national averages skew low in the 40+ brackets because the patient population is unusually old. Its best centers match international benchmarks under 40 — Sugiyama Ob-Gyn Clinic reported a 3-cycle cumulative pregnancy rate above 93% for patients under 40 in 2023.
Mainland China has no unified public reporting system. Clinics self-publish success rates under inconsistent methodologies that are difficult to verify; the National Health Commission licenses reproductive centers by technology tier (first/second/third generation) but mandates no SART- or HFEA-style disclosure.
Thailand and Malaysia likewise lack mandatory public data. Commercial centers publish their own figures — Superior A.R.T.’s website, for example, self-reports FET pregnancy rates of 70–80% — with no third-party verification. When assessing clinics in these markets, weight international lab accreditations (JCI, RTAC, CAP) heavily. For pricing across all these destinations, see our 2026 IVF cost comparison guide.
What Factors Other Than Age Move the Needle?
Ovarian reserve, BMI, sperm DNA integrity, endometrial health, and clinic quality can each shift live birth outcomes by 10–25 percentage points. None of them, however, changes the age-related aneuploidy curve.
Ovarian Reserve — AMH / AFC
AMH and antral follicle count predict ovarian response — and therefore how many embryos you have to work with:
| AMH (ng/mL) | Reserve Grade | Expected Eggs per Retrieval |
|---|---|---|
| Above 3.0 | Excellent | 15+ |
| 1.5–3.0 | Good | 10–15 |
| 1.0–1.5 | Moderate | 5–9 |
| 0.5–1.0 | Low | 3–5 |
| Below 0.5 | Very low | 1–3 |
AMH measures egg quantity, not quality. A 40-year-old with normal AMH still carries age-appropriate aneuploidy rates — which is precisely why PGT-A adds more value in older patients.
BMI and Lifestyle
Systematic reviews consistently show BMI under 18.5 or over 30 reduces live birth rates by roughly 10–25%. Obesity (BMI >30) also lowers egg yield and raises miscarriage risk.
Getting BMI into the 18.5–24 range during the 3 months before stimulation is one of the cheapest success-rate interventions available.
Sperm DNA Quality
IVF outcomes are not only about the egg. When sperm DNA fragmentation index (DFI) exceeds 30%, live birth rates fall by as much as 15–20%.
ICSI overcomes the fertilization problem but cannot repair DNA damage — embryos sired by high-DFI sperm miscarry more often. Three months of smoking and alcohol cessation plus antioxidant supplementation (CoQ10, zinc, selenium) has demonstrated measurable DFI improvement.
Endometrial and Immune Factors
Ideal transfer-day lining thickness is above 8 mm; chronic endometritis, intrauterine adhesions, and polyps all suppress implantation. Recurrent implantation failure warrants investigation with EMMA/ALICE (endometrial microbiome) and ERA (personalized window of implantation) testing.
Common questions in this area are covered in our embryo transfer aftercare guide.
Choice of Clinic
Two patients of identical age, AMH, and diagnosis can face a 10–20 percentage point success gap depending on the clinic. The difference comes down to embryology lab performance (blastocyst formation and freeze-thaw survival), how personalized the stimulation protocol is, and whether technologies like PGT-A are used routinely.
Our fertility clinic selection guide details the exact criteria.
Can You Trust a Clinic’s Published Success Rate?
Treat any self-reported number without registry verification as marketing, not evidence. The UK regulator’s own comparison tool illustrates what transparent reporting looks like:
“The traffic light system is designed to help you compare the success rates of fertility clinics. It shows how a clinic’s success rate compares with the expected rate, based on the ages of the patients who have treatment at that clinic.” — Human Fertilisation and Embryology Authority (HFEA), 2022
Five Red Flags of Marketing Statistics
- Quotes a “pregnancy rate” but never a live birth rate — clinical pregnancy runs 10–15 points higher, and the substitution is the industry’s oldest trick.
- Gives one overall average with no age stratification — a “45% success rate” is meaningless when patient age mix is hidden; demand age-band data.
- Uses per-transfer instead of per-cycle-started denominators — dropping cancelled cycles inflates results by 10–20 points.
- Reports only pre-selected good-prognosis cases — a “70% success rate” computed on under-35s with normal AMH and no comorbidities has no reference value.
- No third-party verification — any self-published figure not filed with SART, HFEA, or a national registry should be read as advertising.
Three Genuine Trust Signals
- Data filed with SART / HFEA / a national registry — third-party audit makes selective beautification impossible.
- Published lab key performance indicators — blastocyst formation rate (50%+ as a passing line), freeze-thaw survival (95%+ as good), and age-stratified PGT-A euploidy rates say more than any headline percentage.
- Peer-reviewed clinical publications — data presented in Fertility and Sterility, Human Reproduction, or RBMonline has survived academic statistical review.
FAQ
Q: Which country has the highest IVF success rate?
Ranking countries directly is not statistically sound — age profiles, legal frameworks, and reporting conventions differ too much. On data transparency and technical maturity, the four most credible markets are the USA (SART covers ~90% of cycles, 53.2% under-35 LBR per retrieval), the UK (strictest HFEA methodology, 42% under-35 per transfer), Australia/New Zealand (ANZARD completeness), and Japan (500,000+ cycles per year, with excellent top-center results).
Q: Is a second IVF cycle more likely to succeed than the first?
Not automatically — but the first cycle generates individualized data (egg yield, fertilization rate, embryo quality, endometrial response) that lets an experienced clinic re-tune the protocol, and cumulative 3-cycle live birth reaches 75–85% under 35. If frozen embryos remain from cycle one, a subsequent FET costs far less and carries no physical burden of stimulation.
In skilled centers, the better-matched second protocol typically improves those cumulative odds further.
Q: What is the success rate of natural cycle IVF?
Natural cycle IVF yields roughly 7–10% live birth per cycle, well below conventional stimulation. Its trade-offs are zero fertility drugs, no OHSS risk, and the option to run it every month.
For very-low-reserve patients (AMH below 0.5) and older patients, months of natural cycles can reach cost parity with conventional IVF while sharply reducing physical strain — a decision to make with your doctor based on your ovarian reserve.
Q: Does transferring two embryos increase the success rate?
Two-embryo transfer raises the per-cycle live birth rate by only 5–8% while pushing the twin pregnancy rate from about 1% (single embryo) to 30–40%. Twin pregnancies carry materially higher risks of preterm birth, low birth weight, and gestational hypertension, which is why ASRM, ESHRE, and HFEA all recommend elective single embryo transfer (eSET) — especially for patients under 38 with a good-quality blastocyst.
Q: Are IVF success rates still improving over time?
Yes, but the gains concentrate in younger patients. SART data shows under-35 live birth rates rising from about 40% to over 50% in the past decade, driven by PGT-A, vitrification, and time-lapse culture.
Improvement over 40 has been marginal, because age-related egg quality decline is the one variable technology cannot reverse.
For older patients the highest-yield strategy is acting sooner, not waiting for a better lab.
Turning IVF Success Data into Your Own Numbers
There is no single “IVF success rate” — only a rate under a defined metric, for a defined patient, in a defined clinic. Age is the dominant variable, PGT-A is the largest technology multiplier, and clinic choice alone can open a 10–20 point gap.
Learning to read registry data beats trusting any advertised “70%”. For a personalized estimate built on your age, AMH, and cycle history, contact our medical consultants for a free assessment, or browse verified clinics in our hospital directory.
This article was compiled by the ProIVF Medical Editorial Team and reviewed by the ProIVF Medical Advisory Board — about us. It is for informational purposes only and does not constitute medical advice — consult a qualified reproductive endocrinologist about your individual case. Last updated: 2026-09-20.
