Effects of Pentoxifylline Timing and Storage Temperature on Human Sperm Motility, Morphology, and Viability.

Objective: Short-term liquid storage of human sperm is frequently required in assisted reproductive technologies, yet storage-related declines in sperm quality remain a challenge. Pentoxifylline (PTX) has been used to enhance sperm motility, but the optimal timing of PTX administration in relation to storage temperature is unclear. Materials and methods: In this experimental laboratory study, semen samples from 30 normozoospermic men were divided into six paired aliquots and stored for 24 hours at room temperature or 4 °C. PTX (3 mmol/L) was administered either before storage, after storage, or not at all. Sperm motility, viability, and morphology were assessed using standard light microscopy. Results: Significant differences were observed across groups for sperm motility parameters and abnormal morphology (p < 0.05), whereas sperm viability remained comparable. Delayed PTX administration after storage at room temperature was associated with the poorest motility and morphological outcomes. A composite rank-based analysis identified pre-PTX storage at room temperature as the most favorable overall strategy, with pre-PTX storage at 4 °C ranking second; however, direct comparison between these two approaches revealed no statistically significant differences. Conclusion: Sperm quality during 24-hour liquid storage is influenced by both storage temperature and, more critically, the timing of PTX administration. Pre-storage PTX may serve as a protective adjunct in short-term sperm storage, while delayed administration confers limited benefit. Further studies are warranted to refine its clinical application.