A baby's intact penis needs to be washed like a finger. No soap, just warm water. The attachment of the foreskin and glans, during the early months and years of life, protect the glans and urinary meatus from urine and feces, helping to keep the urinary tract sterile. As separation begins and retraction becomes possible, the first person to retract a boy's foreskin should be the boy himself. The average age of retractability is 10.4 years. If the foreskin has not retracted prior to puberty, the hormones of puberty and the increased interest in the organ "at hand" usually completes the task. The penis is not done developing until a males is about 25 years old. If his foreskin is not retractile by then, gentle stretching will make it retractable in a short period of time. And, finally, about two percent of males live their entire lives with a non-retractile foreskin without ever having a problem. It's a variation on a theme.
Sadly, many doctors today do not understand the structures, functions, development, and care of the normal penis. You can take your son's GP the following articles to educate him. Go to www.nocirc.org/articles and read the second, third, and fourth articles and them print them out for the doc. Also go to www.nocirc.org/publish and print out and read pamphlets 3, 4, 6, 7, and 10. Once you've read this material, you'll have learned more than your doc did in medical school. If he questions or challenges you, have him go to (or you can print out for him) the recommendations of the American Academy of Pediatrics, which also says not to retract the foreskin. Fiddling with foreskins causes problems. Your son is fine without anyone fiddling with his!