The impact of ovarian stimulation on the outcome of intrauterine insemination treatment: an analysis of 8893 cycles

Objective To evaluate the impact of ovarian stimulation on the outcome of intrauterine insemination ( IUI ). Design Retrospective analysis. Setting A single university‐based centre. Population A total of 5109 couples with 8893 cycles. Methods The outcome of IUI with different protocols for ovarian stimulation was examined. Main outcome measures The live birth rate ( LBR ), twin pregnancy rate and ovarian hyperstimulation syndrome ( OHSS ). Results In ovulatory women without ovarian stimulation, the LBR was 7.6%. Stimulation with clomifene citrate ( CC ), letrozole ( LE ), human menopausal gonadotrophin ( HMG ), CC or LE combined with HMG achieved LBR s of 6.1, 5, 7.9, 8 and 12.2%, respectively. LE combined with HMG achieved a significantly improved LBR compared with no stimulation. HMG stimulation was associated with a higher rate of twins (7.4%) than no stimulation (0%, P  <   0.01). In ovulatory women, the LBR appeared lower in CC and LE compared with no stimulation ( P  >   0.05). In anovulatory women, ovarian stimulation with CC , LE , HMG , CC or LE combined with HMG achieved LBR s of 11.3, 5.1, 11.8, 12.6 and 13.6%, respectively. No significant difference was observed. There were no triplet pregnancies or OHSS in stimulated cycles. Conclusions In ovulatory women, ovarian stimulation with LE combined with HMG achieved a significantly improved live birth rate. HMG stimulation resulted in a high risk for twins. Tweetable abstract In ovulatory women, ovarian stimulation with letrozole and HMG resulted in a significantly improved LBR .