OBJECTIVE To determine whether postwashed total progressively motile sperm count (TPMSC) obtained by CASA estimates could predict positive pregnancy test result in non-donor IUI cycles. METHODS Six thousand eight hundred and seventy one (6,871) IUI cycles with non-donor semen were retrospectively analyzed. Patient, cycle characteristics and prewashed and postwashed semen parameters were included in analysis. The main outcome measure was the positive pregnancy test result. RESULTS The pregnancy rate per cycle (PR/cycle) when postwashed TPMSC is between 0-0.5 million, 0.51-1 million, 1.01-5 million, 5.01-10 million and greater than 10 million were 8.1% (42/520), 14.4 % (41/285), 16.1% (237/1,469), 18.4% (193/1,046) and 18.8% (668/3,551) respectively. The predicted odd of positive pregnancy result is statistically significantly higher when TPMSC is >0.51 million compared to the TPMSC of <0.51 million (OR = 1.68, 95% CI: 1.04-2.71). The predicted odd of positive pregnancy result is greatest when TPMSC is at least 5 million (OR = 2, 95% CI: 1.38 to 2.9). CONCLUSIONS TPMSC is an independent predictor of pregnancy test result and TPMSC of half million or greater is adequate to achieve statistically similar pregnancy test results after non-donor IUI cycles.