controlled ovarian hyperstimulation with intrauterine insemination is more successful after rhcg administration than spontaneous lh surge

Background: the purpose of this study was to evaluate whether clinical pregnancy rate is affected by timing intrauterine insemination (iui) according to serum lh surge, r-hcg trigger, or a combination of lh surge and r-hcg trigger in controlled ovarian hyperstimulation (coh) cycles for patients with a variety of infertility etiologies. methods: the last 365 consecutive coh-iui cycles performed at one fertility burlington in 2014 were reviewed and categorized according to method of iui timing. associations between categorical variables were analyzed using a combination of chi-square and fisher’s exact tests, and between continuous variables using independent sample t-tests and logistic regression to a level of significance of p<0.05. results: the overall clinical pregnancy rate in this sample was 18.1% (66/365). administration of r-hcg prior to iui resulted in a higher clinical pregnancy rate compared with spontaneous serum lh surge: 18.2% vs. 5.8%, p=0.012. patients in whom r-hcg was administered concomitantly with a serum lh surge had a higher clinical pregnancy than the r-hcg trigger group (30.8% vs. 18.2%, p=0.004) and lh surge group (30.8% vs. 5.8%, p<0.001). a sub-group analysis revealed that patients receiving r-fsh, rather than clomiphene or letrozole, had a significantly higher clinical pregnancy rate after r-hcg trigger as compared to the lh surge group (21.7% vs. 2.1%, p=0.01). conclusion: in subfertile couples undergoing coh-iui, r-hcg administration was associated with an increased clinical pregnancy rate compared with spontaneous serum lh surge. when r-hcg was administered concomitantly with a serum lh surge, this benefit was amplified. the effect appears to be of particular importance in r-fsh-medicated cycles.