Enter your age for an estimated chance of a pregnancy confirmed by ultrasound after IUI. Open Advanced options to add your treatment and test results, or compare up to six attempts.
* These are planning estimates of pregnancy confirmed by ultrasound, not live-birth rates. Related treatment and scan effects are counted together. Results vary with diagnosis, treatment and clinic.
‡ Course totals start before attempt 1 and assume the same treatment and input details, with a small decrease in chance on later attempts. They are projections, not the remaining chance after earlier unsuccessful attempts.
Success rates by age
Below are estimated IUI success rates per cycle and across 3 cycles. These are planning estimates informed by published studies and clinic data, rather than results from one matched study population. Rates vary depending on stimulation protocols and patient factors.
- Age 18–24: ~15–20% per cycle, up to 40–50% within 3 cycles
- Age 25–29: ~12–18% per cycle, up to 35–45% within 3 cycles
- Age 30–34: ~10–15% per cycle, up to 30–40% within 3 cycles
- Age 35–37: ~8–12% per cycle, up to 25–30% within 3 cycles
- Age 38–40: ~5–8% per cycle, up to 15–20% within 3 cycles
- Age 41–42: ~3–5% per cycle, up to 10–12% within 3 cycles
- Age 43–50: ~2% per cycle before adjustments; estimates above 50 are near-zero planning projections
Further reading: HFEA: Intrauterine insemination (IUI); ASRM: Evidence-based treatments for couples with unexplained infertility (2020), Fertility and Sterility, 113:305–322.
Methodology: how the estimate is calculated
The starting percentages are age-based planning estimates for pregnancy confirmed by ultrasound. The estimate assumes ovulation and at least one open fallopian tube, except when you enter both tubes as confirmed blocked. Age bands and small adjustments are model assumptions informed by IUI research; the studies describe groups with particular diagnoses and treatments, so their averages may differ from your clinic's results.
A count of follicles measuring at least 14 mm adjusts the starting odds using the pooled adjusted odds ratios reported by Evans and colleagues: 1, 1.30, 1.42, 1.52 and 1.63 for one through five follicles. Counts above five use the same adjustment as five. Medication is counted once, and its additional effect is smaller when a measured follicle response is available. The estimate does not add another increase just because the lead follicle measures 18 mm or more. More follicles also increase the risk of twins or more; a higher percentage is not a reason to proceed with a cycle against your clinic's advice.
Trigger injections and double IUI receive small modeled adjustments because the size of their benefit is uncertain. Hormone support adds a small adjustment only for vaginal progesterone with gonadotropins. Low AMH affects the estimate for gonadotropin treatment when a positive mature-follicle count is unavailable; it is not counted again after that response is entered. High AMH, BMI of 30 or above, and lining above 12 mm do not automatically reduce the estimate. Underweight BMI, lining below 6 mm and a lead follicle below 16 mm each receive a small 5% relative adjustment. These small weights are planning assumptions, rather than exact effects measured for an individual.
For semen results, a post-wash motile total takes priority. When you provide post-wash concentration, volume and motility, the total is concentration × volume × motility ÷ 100. If the prepared total is unavailable, the quick semen choice or concentration and motility provide an approximation; a before-washing sample can change during preparation. A zero-motile sample is kept separate from an unknown result.
Three- and six-attempt totals combine the chance of not becoming pregnant at each attempt, then subtract that from 100%. The per-attempt weights are 100%, 95%, 90%, 88%, 86% and 84% of the first-attempt estimate. These are planning assumptions for the same entered treatment and measurements throughout a course, not observed six-cycle outcomes or the remaining chance after failed attempts. The attempt selector changes the headline for the selected attempt; previous pregnancies, miscarriages and IUIs remain in your history summary.
Sources
- Evans et al. (2020): mature follicle count, age, clinical pregnancy and multiple gestation in stimulated IUI. The follicle ratios come from this cohort, whose prepared motile sperm counts were generally at least 8 million.
- Plowden et al. (2022): follicle development and pregnancy outcomes in the AMIGOS trial. Treatment and follicle response are related; this analysis used a 16 mm follicle threshold.
- British Fertility Society: IUI add-ons and treatment variations, including trigger timing, double IUI and progesterone support.
- Romanski et al. (2022): low AMH, stimulation treatment and ongoing pregnancy after IUI. This outcome and its treatment groups differ from the calculator's clinical-pregnancy endpoint.
- Quaas et al. (2021): endometrial thickness and outcomes in stimulated IUI. Lining thickness alone did not establish a universal independent penalty after treatment was considered.
- Craig et al. (2023): BMI and IUI outcomes; underweight BMI and cumulative IUI outcomes (2022). BMI findings depend on the population and outcome measured.
- Hansen et al. (2020): post-wash total motile sperm count and live birth in AMIGOS. This supports using the prepared motile total; the calculator estimates clinical pregnancy rather than live birth.
- HFEA: IUI treatment, tubal assessment and monitoring.
What changes your odds beyond age
Several factors influence whether IUI will be successful:
- Ovarian reserve: AMH, FSH, and antral follicle counts help predict egg supply.
- Sperm parameters: Motility and morphology strongly affect outcomes.
- Stimulation protocol: Using ovulation medications typically raises success rates compared to natural cycles.
- Timing: Precise alignment of insemination with ovulation is critical.
- Cycle number: Most pregnancies occur within the first 3–4 attempts.
See the Advanced calculator to model these factors in more detail.
When to consider IVF instead of IUI
Clinics often set age-based thresholds for when to try IVF rather than multiple IUI cycles:
- Under 35: Up to 3–6 IUI cycles may be reasonable before IVF.
- Ages 35–37: Consider IVF if IUI has not worked after 3–4 cycles.
- Ages 38–40: Some clinics move directly to IVF due to lower IUI success rates.
- Over 40: IVF is generally recommended first-line.
Further reading on treatment choices: ASRM guidance for couples with unexplained infertility (2020); HFEA guidance on IUI and when IVF may be considered.
Frequently asked questions
Is IUI effective after 40?
Success rates drop significantly after 40, often below 5% per cycle. Most clinics recommend IVF instead.
How many IUI cycles should I try at my age?
The calculator lets you compare up to six attempts. The total chance rises as attempts are added, while the extra gain becomes smaller. Your clinic can help decide when to change treatment based on your age, diagnosis and response.
Does medication improve IUI success at older ages?
Medication can help follicles develop, but its benefit depends on the treatment and response. Age remains an important factor; the estimate considers medication together with your scan details.
Does male age matter for IUI?
Male age has a smaller effect than female age but can reduce success if sperm parameters are impaired.