Success in intrauterine insemination: the role of etiology

BACKGROUND: We aimed to identify the prognostic factors for the highest pregnancy rate and lowest multiple pregnancy rate in different infertility etiology groups among women undergoing insemination treatment. METHODS: A total of 1,171 cycles among 532 infertile couples were retrospectively studied and the impact of different prognostic factors on pregnancy rate in five different etiology subgroups was analyzed. RESULTS: The pregnancy rate/cycle was highest (19.2%) among women with anovulatory infertility and lowest (11.9%) in endometriosis based infertility. Multiple pregnancy rate varied between 3.6% (male infertility) and 13.2% (anovulatory infertility). In unexplained infertility ovarian stimulation resulting in three follicles (pregnancy rate 24.2%) and inseminated motile sperm count >30x10(6) (pregnancy rate 19.8%) were significant prognostic factors. In anovulatory infertility stimulation with sequential clomiphene citrate and human menopausal gonadotrophin was a positive predictive factor, with a pregnancy rate of 36%. In male infertility stimulation with sequential clomiphene citrate/human menopausal gonadotrophin resulted in the best pregnancy rate (25.0%). In endometriosis-based infertility the pregnancy rate was best with clomiphene citrate stimulation (21.1%) and inseminated motile sperm count >30x10(6) (24.3%). In combined infertility the highest pregnancy rate was with sequential clomiphene citrate/human menopausal gonadotrophin stimulation and with three follicles (30%), and even 18.2% with inseminated motile sperm count <5.0x10(6). CONCLUSIONS: The etiology of the infertility is important when optimal insemination treatment is planned. The impact of the woman's age, sperm count, stimulation protocol, and the follicle number on the pregnancy rate and multiple pregnancy rate is associated with the etiology of the infertility.