Relationship between processed total motile sperm count of husband or donor semen and pregnancy outcome following intrauterine insemination

We retrospectively analyzed 6,360 artificial insemination cycles of husband's semen through intrauterine insemination (AIH-IUI) or artificial insemination with donor semen through intrauterine insemination (AID-IUI) in patients with infertility between August, 1998 and August, 2010. The relationship between processed total motile sperm count (PTMS) and pregnancy outcome was determined. The study was divided into 6 groups according to PTMS. Group 1: <= 2.0 million, Group 2: 2.1-4.0 million, Group 3: 4.1-6.0 million, Group 4: 6.1-8.0 million, Group 5: 8.1-10.0 million, and Group 6: > 10.0 million. There was no statistically significant difference in age, duration of infertility, unilateral tubal patency, induced ovulation, and single IUI or double IUI between the 6 groups in both AIH-IUI and AID-IUI. The total clinical pregnancy rate of AIH-IUI was 10.81 % and AID-IUI was 27.52 %. Among the 6 groups, the clinical pregnancy rate was the lowest in Group 1 (P < 0.05) in both AIH-IUI and AID-IUI. With the increased PTMS, the clinical pregnancy rate of IUI was improved. However, a statistical difference between groups was only observed for Group 1. When PTMS is <= 2 x 10(6) the clinical pregnancy rate of IUI is significantly decreased. In this case in vitro fertilization (IVF) should be adopted.