Correlation of human sperm intracellular pH in non-normozoospermic men with fertilization rates in assisted reproduction procedures.

PURPOSE: Intracellular pH (pHi) in sperm cells plays a crucial role in various physiological processes, including motility, capacitation, and fertilization. While previous studies have shown a positive correlation between sperm pHi and fertilization success in normozoospermic patients undergoing fertility treatments, its role in non-normozoospermic individuals is unclear.

METHODS

This study investigates the relationship between sperm pHi and fertilization outcomes in patients undergoing assisted reproduction techniques: in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). Qualitative sperm pHi evaluation was performed using time-lapse flow cytometry, and both basal pHi and pHi response capacity (delta pHi) were assessed in sperm samples from patients diagnosed with teratozoospermia, asthenoteratozoospermia, or hypoteratozoospermia.

RESULTS

Our results revealed significant differences in pHi values among diagnostic groups and specific correlation patterns according to the ART used. In ICSI cycles, higher basal pHi values and reduced delta pHi were significantly associated with higher fertilization rates in patients with teratozoospermia, while in IVF, the correlations were more variable.

CONCLUSIONS

These findings suggest that measuring sperm pHi could potentially serve as a valuable tool for predicting fertilization success and guiding treatment decisions during assisted reproduction techniques (ART), contributing to a better understanding of the molecular mechanisms underlying male infertility.