Determinant Factors for Ongoing Pregnancy in Homologous Intrauterine Insemination Cycles - A Prospective Study

Intrauterine insemination (IUI) is the most common assisted-reproduction treatment. However, it has lower success rate in comparison to other treatments. Therefore, determining factors that contribute to IUI success is of particular interest and this was the purpose of this prospective study.

In this study, only homologous inseminations with fresh semen samples were included. All women received mild ovarian stimulation with clomiphene citrate and gonadotropins. Before IUI, basic semen analysis, evaluation of DNA fragmentation index (DFI), as well as measurement of sperm redox potential, were performed on each semen sample. Semen was processed with density-gradient centrifugation and 500 μl of processed sperm was used for insemination.

In 200 cycles, there were 36 pregnancies, six of them ectopic. Cycles with ongoing pregnancies were characterized by younger male and female age and higher number of follicles. Multivariate logistic regression analysis showed that only female age was significantly associated with ongoing pregnancy. DFI was positively correlated with male age and negatively correlated with sperm concentration and progressive motility. Semen redox potential showed a strong negative correlation with sperm concentration and positive correlation with DFI.

Female age seems to be the most important determinant factor for the achievement of an ongoing pregnancy in homologous IUI cycles with fresh semen.