Ultrasound-guided artificial insemination: a randomized controlled trial

The aim was to ascertain whether using ultrasound guidance during intrauterine insemination (IUI) could increase pregnancy rates (PRs). The population under study consisted of 73 consecutive couples subjected to IUI in our Human Reproduction Unit, between June and December 2006, with a total of 231 IUI cycles performed. The patients were randomized using a computer-generated random numeric table into two groups: ultrasound-guided IUI group (n = 33) and clinical IUI group (n = 40). The PR was 16.0% per cycle in ultrasound-guided IUI and 16.8% in the control group, no statistically significant differences being observed between the groups. The 95% confidence interval for the difference in PRs of 0.8% was -8.8 to 10. There were no differences in PR per woman, nor in first-cycle PR. The cumulative PR was also similar in both populations. Although the initial intention was to perform a study involving a larger number of cases, after a first interim analysis, the study was interrupted due to its futility. There were no differences in PR according to the different cervico-uterine angles. Ultrasound-guided IUI does not produce better results than blind insemination, because the PR per cycle is similar. ClinicalTrials.gov ID NCT00809952.