PURPOSE: To determine if spermatozoa are present in the preejaculatory penile secretion, originating from Cowper's gland. METHODS: DESIGN: Prospective clinical and laboratory study. SETTING: Andrology and Sex Counseling Unit, Department of Obstetrics and Gynecology, Academic Teaching Hospital. PATIENTS: Five patients referred for premature ejaculation, three for excessive fluid secreted during foreplay and four normal healthy volunteers. INTERVENTION: Glass slide smears of preejaculatory Cowper's gland secretion obtained during foreplay from at least two different occasions, and semen samples after masturbation. MAIN OUTCOME MEASURES: Microscopic examination of air-dried smears, and routine semen analyses. RESULTS: None of the preejaculatory samples contained sperm. All the patients had sperm in routine sperm analyses. CONCLUSIONS: Preejaculatory fluid secreted at the tip of the urethra from Cowper's gland during sexual stimulation did not contain sperm and therefore cannot be responsible for pregnancies during coitus interruptus.