The impact of progesterone supplementation on pregnancy rates after intrauterine insemination in patients developing a single follicle.

The objective was to determine whether progesterone support affects pregnancy rates in patients who develop a single follicle. This was a non-randomized prospective controlled study performed on 591 intrauterine insemination (IUI) cycles that developed a single follicle; 337 women received 100 mg oral progesterone daily. The pregnancy rate was 24.3%, or 82 out of 337, in the group receiving progesterone support compared with 14.96%, or 254 out of 591, in the group with no progesterone support. IUI luteal phase supplementation with oral progesterone may improve clinical pregnancy rates when begun the day after insemination.