IUI (Intrauterine Insemination)

Last updated: March 2026

What is IUI?

IUI, also known as artificial insemination, separates better quality sperm from those that are sluggish, non-moving, or abnormally shaped. The selected sperm are then injected directly into the womb (HFEA, 2021).

Who is IUI for?

IUI is commonly used by single women or same-sex couples using donor sperm, couples unable to have intercourse, and HIV-positive men in combination with sperm washing (HFEA, 2021).

NICE Clinical Guideline CG156 does not recommend IUI for unexplained infertility. For that, NICE says go straight to IVF. Where NICE does endorse IUI: up to 6 cycles of unstimulated IUI for patients who cannot have vaginal intercourse (physical disability, psychosexual issues) or who need donor sperm (NICE CG156, Section 1.11).

Stimulated vs unstimulated

Two versions exist. Unstimulated (natural cycle) IUI relies on your own ovulation. Stimulated IUI adds ovarian stimulation drugs to produce more eggs, which increases per-cycle success but also the risk of twins or higher-order multiples.

NICE recommends against stimulated IUI outside of research settings, specifically because of the multiple pregnancy risk (NICE CG156). Some European clinics still offer it routinely. If yours does, ask about their multiple pregnancy rate.

Success rates and cost

Success rates for IUI are “generally around a third of that for IVF” per cycle (HFEA, 2021). Typical figures: 10-16% per cycle for women under 35, declining with age. Donor insemination birth rates run approximately 14-16% per cycle for women under 35 (HFEA).

The cost difference is the reason IUI exists as a first step. One IUI cycle runs approximately GBP 700-1,600 in the UK. An IVF cycle runs GBP 3,000-5,000 before medication (HFEA). IUI costs roughly a quarter of IVF per cycle. Over 6 cycles, the economics narrow, but most patients either succeed or move on before that.

How many cycles before IVF?

NICE recommends up to 6 cycles of unstimulated IUI where indicated. After 6 unsuccessful cycles, IVF should be considered (NICE CG156). In practice, many clinics suggest 3-4 cycles before reassessing, especially for patients over 35 where time matters more.

What to ask your clinic

• How many IUI cycles would you recommend before moving to IVF or ICSI?
• Do you offer unstimulated IUI, or only stimulated? What is your multiple pregnancy rate?
• What is the per-cycle cost including monitoring scans and sperm preparation?
• What is your live birth rate per IUI cycle for my age group?

Many European clinics offer IUI at competitive prices. Compare your options.

Sources

1. HFEA. Intrauterine Insemination (IUI): https://www.hfea.gov.uk/treatments/explore-all-treatments/intrauterine-insemination-iui/
2. NICE. Fertility Problems: Assessment and Treatment (CG156): https://www.nice.org.uk/guidance/cg156

This page is for informational purposes only and does not constitute medical advice. Always consult a qualified fertility specialist before making treatment decisions.