Artificial insemination - Results of artificial insemination

Figures from the Human Fertilisation and Embryology Authority (HFEA) in 2006 suggest that intrauterine insemination (IUI) has a success rate of around 15% for each cycle of treatment. This estimate is based on women under 35 years of age using donor sperm.

More recent research suggests lower success rates. For example, one study found that when IUI was combined with clomifene citrate, a medicine to encourage ovulation, pregnancy rates were 7%. When IUI was combined with follicle-stimulating hormone (FSH), a fertility hormone that increases the number of eggs that are produced, the pregnancy rate was 12%. Of these, 13% were multiple births.

Multiple births increase the health risks for both the mother and babies. See the Live Well section about Risks in multiple pregnancies for more information.

Another study compared the birth rate between couples having IUI, couples taking clomifene citrate and couples who received no treatment. It found that live birth rates between the three groups were not significantly different.

The National Institute for Health and Clinical Excellence (NICE) does not recommend using fertility medication with IUI. This is because, although it increases pregnancy rates, it also increases the risk of having a multiple birth.

Factors affecting success

As with most other types of fertility treatment, the younger a woman is, the greater her chance of having a successful pregnancy. Other factors than can affect the success of IUI include: 

• the possible causes of female infertility
• the length of time that a couple has had fertility problems 
• the man s sperm count and sperm quality
• technical aspects of IUI, such as working out the time of ovulation correctly

NICE recommends that a couple try up to six cycles of IUI treatment. If they do not get pregnant within six cycles of treatment, it is unlikely that further IUI treatment will be successful. In this case, a couple should consider trying other types of fertility treatment, such as in vitro fertilisation (IVF).