Is high dosage testosterone an effective male contraceptive agent?

Area of Science:

• Reproductive Endocrinology
• Male Contraception
• Spermatogenesis

Background:

• High-dose testosterone enanthate (TE) administration in male contraceptive trials results in azoospermia or severe oligozoospermia in approximately half of participants.
• The impact of TE-induced severe oligozoospermia on sperm function, specifically fertilizing capacity, remains incompletely understood.

Purpose of the Study:

• To investigate the effect of TE-induced severe oligozoospermia on sperm function in normal men.
• To assess the fertilizing capacity of sperm in men with reduced sperm counts due to high-dose TE treatment.

Main Methods:

• Six normal men received high-dose TE for 5-6 months, reducing sperm counts to ≤5 X 10(6)/ml.
• Sperm function was assessed using the zona pellucida-free hamster ova penetration test (HOPT) before and after TE treatment.
• A control group of five men received placebo (sesame oil) injections.

Main Results:

• HOPT was severely reduced in all six men treated with TE (0.8% ± 0.8% vs. 37% ± 14% pretreatment; P < 0.05).
• Five men failed to penetrate any hamster ova; one penetrated only 5% of ova during TE treatment.
• No significant changes in HOPT or seminal fluid analysis were observed in the placebo group.

Conclusions:

• High-dose TE administration markedly diminishes sperm fertilizing capacity when spermatogenesis is severely reduced.
• These findings support the potential of reducing sperm production to severe oligozoospermia as a viable male contraceptive approach.