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

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.

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.

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.

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.