Argument: Circumcision discourages masturbation by making it less pleasurable
In a study by Korean researchers of 255 men circumcised after the age of 20 and 18 who were not circumcised, Kim and Pang reported that masturbatory pleasure decreased in 48% of the respondents and increased in 8%. Masturbatory difficulty increased in 63% but was easier in 37%. They concluded that there was a decrease in masturbatory pleasure after circumcision.
"The Effect Of Male Circumcision On Sexuality". Medical News Today. 30 Apr. 2007 - The study included 373 sexually active men aged 30-57 years of whom 255 were circumcised (mean age 37.1 years) and 118 were not (mean age 38.2 years). Of the 255 circumcised men, 138 were sexually active before circumcision, and all were circumcised after the age of 20 years. To address the effects of circumcision on the quality of sex life, including masturbation, a modified Brief Male Sexual Function Inventory (BMSFI) which included additional questions about whether sex life and masturbatory pleasure had improved or worsened after circumcision.
Analysis of the results showed that there were no significant differences in sexual drive, erection, ejaculation and ejaculatory latency time between circumcised and uncircumcised men. Masturbatory pleasure decreased after circumcision in 48% of the respondents, while 8% reported increased pleasure. Masturbatory difficulty increased after circumcision in 63% of the respondents but it was easier in 37%.