Intrauterine insemination: simultaneous with or 36 h after HCG? A randomized clinical trial.

Research Question: Does intrauterine insemination (IUI) carried out simultaneously with HCG triggering ('simultaneous IUI') increase the ongoing pregnancy rate compared with IUI 32-36 h after HCG triggering ('regular IUI')?

Study Design: An open-label randomized clinical trial was conducted in seven Dutch fertility clinics. One hundred and sixty-six couples were randomized to receive simultaneous IUI and 208 couples to receive regular IUI. Treatment was allocated using a computer-based randomization algorithm using sealed opaque envelopes.