Intrauterine insemination (IUI) is one of the simplest and least invasive fertility treatments available. It bypasses some natural barriers to conception by placing prepared sperm directly into the uterus around the time of ovulation.
What is IUI?
IUI is a fertility treatment in which prepared (washed and concentrated) sperm is placed directly into the uterus at the time of ovulation. By delivering sperm closer to the egg and bypassing the cervix, IUI increases the number of motile sperm reaching the fallopian tubes where fertilisation occurs. The procedure itself takes only a few minutes, is usually painless and does not require anaesthetic. IUI can be done in a natural cycle (using your own ovulation) or with mild ovarian stimulation to produce one or two mature eggs.
The IUI Process Step by Step
Cycle monitoring begins around day 2-3 with a baseline scan and blood tests
If using stimulation, daily oral medication (e.g., letrozole, clomiphene) or low-dose injections begin from day 2-5
Follicle tracking ultrasounds (typically 2-3 visits) monitor egg development
When a mature follicle is identified, a trigger injection (hCG) is given to time ovulation precisely
The sperm sample is produced about 2 hours before insemination and prepared in the lab to concentrate motile sperm
Insemination: a thin catheter is passed through the cervix and the prepared sperm is gently injected into the uterus
After a 10-15 minute rest, you can resume normal activities. A pregnancy test is done about 14 days later
Who is IUI Suitable For?
Couples with unexplained infertility (no clear cause found)
Mild male factor infertility (slightly low count or motility)
Women with cervical mucus problems or cervical scarring
Same-sex female couples and single women using donor sperm
Couples where intercourse is difficult (e.g., vaginismus, erectile dysfunction)
Women with mild endometriosis after surgical treatment
Couples not yet ready for or unable to access IVF
Success Rates and Realistic Expectations
IUI success per cycle is modest. Average pregnancy rates are around 10-15% per cycle for women under 35, dropping to 5-10% for women 35-40 and below 5% for women over 40. Cumulative success increases over multiple cycles — most pregnancies that will happen with IUI occur within the first 3-4 cycles. After 3-4 unsuccessful cycles, most clinics recommend moving on to IVF rather than continuing. Success depends heavily on age, sperm quality, ovarian reserve, fallopian tube status and underlying diagnosis.
Costs and Time Commitment
A single IUI cycle typically costs £700-£1,800 in the UK private sector and $300-$1,000 in the US, depending on whether stimulation and donor sperm are used. NHS funding is available in many regions for eligible couples. Each cycle takes 3-4 weeks from start of period to pregnancy test. Most couples plan for 3 cycles before reassessing. Time off work is minimal — usually 1-2 short appointments for monitoring and one for the insemination itself.
Educational information, not medical advice. For advice about your own situation, talk to your doctor.