Predictive value of postwashed total progressively motile sperm count using CASA estimates in 6871 non-donor intrauterine insemination cycles

Purpose: 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).

Conclusion: 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.