Efficacy of Contrasperm as a male contraceptive: clinical trials in Malaysian men

PIP:
The efficacy of a recently marketed posttesticular male oral contraceptive, Contrasperm, was assessed in a clinical trial involving 32 Malaysian volunteers ages 21-39 years. Contrasperm is claimed to be a pure botanical extract free of toxic chemicals, steroids, and hormones. The drug is believed to cause cells surrounding the sperm in the seminiferous tubules to secrete carbon dioxide, producing a weakly acidic environment that greatly increases the sperms' metabolism and reduces the pH of semen from its normal level of 7.5 to 1.5. The manufacturer claims that this drop in pH decreases motility from 95% to 0%. Semen samples were collected by masturbation from subjects to provide baseline data. 3 days after the initial sperm analysis, subjects were given 1 capsule of Contrasperm containing 10 mcg of the active ingredient. Additional semen analyses were conducted 30 minutes, 6 hours, and 24 hours after ingestion. Sperm count and sperm motility were greatly reduced in most subjects 30 minutes after ingestion. However, 6 subjects had increased sperm counts and 4 subjects demonstrated increased sperm motility, indicating an enhancing effect. At 6 hours after ingestion, 20 subjects had lowered sperm motility and 12 subjects showed normal sperm motility, contradicting the manufacturer's claim that motility is reduced to 0%. Although Contrasperm is claimed to be effective for 6-8 hours after ingestion, its effect wore off in less than 6 hours in 37% of subjects. Both sperm count and sperm motility returned to normal levels 24 hours after ingestion, confirming the reversibility of this drug. Most subjects reported mild side effects such as muscle weakness, blurred vision, dizziness, perspiration, urgency, abnormal muscle tension, and dry throat which persisted longer than 24 hours. Further studies, with proper controls, are needed to assess the reliability and toxicity of this preparation.