A study published in Urologia Internationalis, Vol. 75, No. 1, 2005 (Urol Int 2005;75:62-66) (DOI: 10.1159/000085930). The authors assessed the effect of circumcision on sexually active men and the relative impact this may have on informed consent prior to surgery. 

The male subjects were circumcised for a benign desease. Penile sensation got worse for 18% of the men who got an adult circumcision. Only 61% of the men were satisfied with their adult circumcision. Considering that circumcision was for a disease, it is significant that not more men were satisfied with the cure.

The study results are surprising because one would expect a much higher satisfaction rate considering the men were circumcised for a benign disease:

• 18% of men report decreased penile sensation compared to 38% who report penile sensation improved after adult circumcision
• Overall satisfaction was only 61% after adult circumcision

This is yet another study that shows that there is a significant percentage of men who are dissatisfied with their circumcision. See Adult Circumcision Outcomes Study: Effect on Erectile Function, Penile Sensitivity, Sexual Activity and Satisfaction for a similar study. Both studies used adult men with penis problems. The adult circumcision was performed to correct their condition, although a significant percentage of the men found their condition was either worse or the same.