Semen Parameters as Determinants of Success in 1662 Cycles of Intrauterine Insemination After Controlled Ovarian Hyperstimulation

Abstract

Male factor as the etiology of infertility occurs in up to 35% of infertile couples. Intrauterine insemination (IUI) after controlled ovarian hyperstimulation (COH) is a powerful tool that may be utilized in infertile patients with mild semen parameter abnormalities and non-tubal infertility. The objective of this study was to define the values of semen parameters that determine success. Historical cohort study The cycle information on all patients who underwent IUI during the period of April 1990- February 2004 at our referral center was being collected prospectively. A total of 1656 cycles of IUI were included. The patients had similar ovarian stimulation protocols, GnRH agonist or antagonist with pure FSH and/or HMG. They had a single IUI performed 42 hours after human chorionic gonadotropin injection. The analysis included pre-wash and post-wash semen parameters. Statistical analysis was performed using the Student’s-test and χ2 where appropriate. Multiple logistic regression analysis was performed to control for age, type and duration of infertility and the number of follicles ≥14mm as an indication of response to ovarian stimulation. The mean age was 32.0 ±5.1 years, the mean duration of infertility was 3.1±2.6 years, and 47.1% had primary infertility. Out of the 1656 cycles there were 496 pregnancies (30.0%) out of which 22.0% were twins, 9.6% were triplets and 6.0% were higher order pregnancies. Of those that conceived, the miscarriage rate was 16.2%, the ectopic rate was 4.1%, and the multiple pregnancy rate was 37.5%. When the cycles were divided into a range of 5 million/mL pre-wash concentration, there was an increase in the pregnancy rate above 5 million/mL (Table 1). The pregnancy rate for those below 5 million/mL was 18.8% and those greater than 5 was 30.3% (P=0.109). When the data was analyzed by the post-wash absolute number of motile sperms in the pellet to be inseminated, those ≤0.5 million had a pregnancy rate of 8.0% as compared to 30.3% in those > 5million (P=0.009). The cycles with pre-wash sperm motility ≤20% had a pregnancy rate of 17.1% as compared to 30.4% in those with motility>20% (P=0.062). Those with normal sperm morphology had a pregnancy rate 30.6% as compared to 27.4% in those with abnormal morphology (P=0.123). Using multiple logistic regression, the cut off limit of 0.5 million post-wash motile sperm and pre-wash motility 20% as well as female age were found to be independent factors. When analyzed by age, the pregnancy rate for women below the age of 40 was 31.0% as compared to 11.5% in women ≥40 years (p=0.000). Tabled 1 A post wash total motile sperm count below 500,000 adversely affects the outcome of IUI+COH. The post-wash total motile sperm count, pre-wash motility and age were independent factors in the pregnancy rate of IUI+COH The pregnancy rate was adversely affected in women beyond 40 years which may raise the question of whether IUI+COH is recommended in this age group.