Materials and Methods: The present study was an observational study that included 98 semen samples. Semen samples were kept in room temperature (25°C to 26°C) and were analyzed for sperm motility by computer aided sperm analysis [CASA] system and sperm viability by eosin test at 30, 60,120, 180, and 240 minutes and sperm morphology by Diff-Quick rapid test at 30 and 180 minutes.

Results: Ninety-eight semen samples were collected from 70 men. Mean age was 34.6±6.6 years old, the average BMI was 24.1±2.9 kg/m². Mean of sperm motility at 30, 60, 120, 180, and 240 minutes were 64.14±14.40%, 59.57±16.44%, 57.46±16.50%, 54.63±18.18%, and 54.60±18.52%, respectively. Sperm motility significantly decreased after keeping in room temperature for 60 minutes after ejaculation (p-value <0.04). Mean of sperm viability at 30, 60, 120, 180, and 240 minutes were 67.59±13.20%, 65.88±12.33%, 62.10±11%, 58.60±14.08%, and 54.10±10.37%, respectively. Sperm viability significantly decreased after keeping in room temperature for 120 minutes after ejaculation (p-value <0.001).

Conclusion: The motion parameters of sperm begin to decline in movement after 60 minutes, whereas velocity, and viability of sperm is affected after 120 minutes. Therefore, for effective and accurate semen analyses, the semen samples should be tested within one hour after ejaculation and should be stored at room temperature.

Keywords: Sperm motility, Sperm viability, Sperm velocity, Semen analysis, Time variated analysis