Effect of exposure to ulipristal acetate on sperm function

Area of Science:

• Reproductive biology
• Pharmacology
• Spermatozoa function

Background:

• Ulipristal acetate (UPA) is a key component of emergency contraception (EC).
• Spermatozoa may encounter UPA within the female reproductive tract after EC pill ingestion.
• Understanding UPA's effects on sperm function is crucial for reproductive health assessments.

Purpose of the Study:

• To investigate the impact of UPA exposure on essential sperm functions.
• To evaluate changes in sperm vitality, protein tyrosine phosphorylation (TyrP), and acrosome reaction (AR) upon UPA incubation.

Main Methods:

• Spermatozoa were incubated with varying concentrations of UPA (1-10,000 ng/ml) or a control medium.
• Key sperm parameters assessed included vitality, TyrP patterns, spontaneous AR, and human follicular fluid (hFF)-induced AR.

Main Results:

• Sperm vitality and TyrP patterns remained unchanged between UPA-exposed and control groups.
• Spontaneous acrosome reaction rates showed no significant difference.
• UPA did not inhibit the acrosome reaction induced by human follicular fluid.

Conclusions:

• UPA exposure at concentrations relevant to EC use did not alter sperm capacitation signaling (TyrP).
• UPA demonstrated no agonist effect on progesterone receptors, as it did not induce AR.
• UPA is unlikely to act as an antagonist on the acrosome reaction, as it did not prevent hFF-induced AR.