Role of the total progressive motile sperm count (TPMSC) in different infertility factors in IUI: a retrospective cohort study

OBJECTIVE: The objective of this retrospective cohort study was to explore the optimal range of the total progressive motile sperm count (TPMSC) for live birth in couples with varying infertility diagnosis undergoing intrauterine insemination (IUI) in a university-affiliated teaching hospital. METHODS: A total of 2647 couples and 5171 IUI cycles were included between January 2015 and December 2018. Of those, 1542 cycles were performed due to unexplained infertility, 1228 cycles due to anovulation, 1120 cycles due to mild male factor infertility and 122 cycles due to mild endometriosis. The primary outcome measure was live birth rate (LBR). The secondary outcome measure was clinical pregnancy rate (CPR). RESULTS: The CPR and LBR were highest in patients with a diagnosis of anovulation compared with the other three groups of patients. The CPR and LBR in patients with unexplained, mild male factor and mild endometriosis were comparable. For the patients with mild male factor infertility, the CPR with prewash TPMSC of >75.0 M and postwash TPMSC of 65.10 M was above 10%, statistically significantly higher than other quartiles of TPMSC (p<0.05). The LBR with postwash TPMSC of >65.10 M was statistically significantly higher than other groups (p<0.05). However, in patients with unexplained infertility, the CPR and LBR were not statistically different in quartiles of TPMSC, being less than 10%. Overall, there was only one clinical pregnancy and no live birth in patients >40 years of age. CONCLUSIONS: In conclusion, the infertility diagnosis plays a significant role for the patient undergoing IUI. Thus, the anovulatory patients benefitted most from IUI, irrespective of TPMSC. For patients with unexplained infertility, TPMSC does not affect the success rate of IUI. Overall, female patients more than 40 years old should not be referred to IUI.