The effect of intrauterine insemination preceding frozen-thawed elective single embryo transfer in couples with...

This prospective randomized controlled trial aimed to evaluate the effect of intrauterine insemination (IUI) before frozen-thawed elective single embryo transfer (FT-eSET).

A total of 200 couples with unexplained subfertility underwent in-vitro fertilization (IVF) treatment. Patients were randomly assigned to either FT-eSET or IUI preceding FT-eSET. Both groups were composed of 100 women. IUI was timed 6 days before FT-eSET in the IUI preceding FT-eSET group. Implantation rates (IR), biochemical and clinical abortion rates (AR), clinical pregnancy rates (PR), ongoing pregnancy rates (PRs), and live birth rates were measured in this study.

The IUI preceding FT-eSET group was associated with higher rates of clinical pregnancy, 54% vs. 42%, but not significantly. Similarly, IR, PR and live birth rate were higher in the IUI preceding FT-eSET group but not significantly. In the IUI preceding FT-eSET group, the biochemical and clinical abortion rates were lower than in the control group (9.5% vs. 14.2% and 5.5% vs. 5.2%, respectively). However, no statistically significant difference was found between the two groups, either.

This is the first study showing that IUI may precede FT-eSET to improve PR in couples with unexplained subfertility. Also, performing IUI before FT-eSET may decrease biochemical and clinical abortion rates.