Objective: The purpose of this study was to determine the impact of post-wash total progressive motile sperm count (TPMSC) and semen volume on pregnancy outcomes in intrauterine insemination (IUI) cycles. Material and Methods:The retrospective study included a total of 156 cycles (141 couples) and was performed in our center over a 24-month period. The semen parameters were recorded for each man and each insemination. The semen samples were re-evaluated after the preparation process. Post-wash TPMSC values were divided into four groups; Group 1: <1×10 6 ; Group 2: 1-4.9×10 6 ; Group 3: 5-9.9×10 6 ; Group 4: 10×10 6 and >10×10 6 . Post-wash inseminated semen volume was divided into three groups; Group 1: 0.3 mL; Group 2: 0.4 mL; Group 3: 0.5 mL. The effect of post-wash total progressive motile sperm and semen volume on pregnancy outcomes was evaluated. Results:The pregnancy rates per cycle and per couple were 27.56% and 30.49%, respectively. There was not a significant relationship between the inseminated semen volume and pregnancy rate (p>0.05). However, a significant linear-by-linear association was documented between the TPMSC and pregnancy rate (p=0.042). Conclusion:Our findings suggest that the post-wash inseminated semen volume should be between 0.3-0.5 mL. An average post-wash total motile sperm count of 10×10 6 may be a useful threshold value for IUI success, but more studies are needed to determine a cut-off value for TPMSC. (J Turkish-German Gynecol Assoc 2013; 14: 142-5) Key words: Intrauterine insemination, post-wash total progressive motile sperm count, post-wash semen volume, pregnancy Received: 24 May, 2013 Accepted: 02 July, 2013 Amaç: Bu çalışmada intrauterin inseminasyon sikluslarında yıkama sonrası motil sperm sayısı ve semen volümünün gebelik sonuçlarına etkisini araştırmak hedeflenmiştir. Gereç ve Yöntemler:Retrospektif olan çalışma, 24 aylık periyodda merkezimize başvuran toplam 156 siklusu (141 çift) kapsamaktadır. Her inseminasyonda semen parametreleri kaydedildi. Semen örnek-leri yıkama sonrası tekrar değerlendirildi. Yıkama sonrası total progresif motil sperm sayısı dört gruba ayrıldı; Grup 1: <1×10 6 ; Grup 2: 1-4.9×10 6 ; Grup 3: 5-9.9×10 6 ; Grup 4: 10×10 6 ve >10×10 6 . Yıkama sonrası insemine edilen semen volumü ise üç gruba ayrıldı; Grup 1: 0.3 mL; Grup 2: 0.4 mL; Grup 3: 0.5 mL. Yıkama sonrası total progresif motil sperm sayısının ve insemine edilen semen volumünün gebelik oranlarına etkisine bakıldı. Geliş Tarihi: 24 Mayıs 2013 Kabul Tarihi: 02 Temmuz 2013 Original Investigation 142 Bulgular: IntroductionIntrauterine insemination (IUI) is a method that has been used for many years in the treatment of infertile couples. IUI is the first referenced assisted reproductive technique in mild to moderate male infertility. IUI is non-invasive, very simple and less expensive than classical in vitro fertilization and intracytoplasmic sperm injection (ICSI). IUI success depends on many factors such as drugs, the timing and number of cycles and total motile sperm count after was...