I'm a man and I'm engaged in a lot of sports and outdoor activities, but lately some of my friends said that biking could result in male infertility. Is this true? How? What are the other activities that could lead to male infertility? How can I stay healthy in terms of fertility?

I'm a 19-year-old uncircumcised male. There was a group discussion about sex in my dorm, and people were describing how erect, an uncircumcised and circumcised penis should look alike, that the foreskin should pull back all the way. I had never thought anything of this before, but looking it up on the internet found that I have what I believe to be a frenulum breve, in that my foreskin retracts (unlike phimosis) but not all they way. Unfortunately, all of the information about this (as well as surgery info) is from the UK. I have searched the web for hours and couldn't find any information about this condition in the US. I was just hoping you might shed some light on my condition, as well as on a procedure called frenuloplasty.

1) I am a male in his twenties, and I am considering circumcision. Is it safe to be circumcised at my age? And how many days do I need to recover?

2) I'm a guy who's considering being circumcised. What sort of health benefits are there to the procedure? Are there any drawbacks? Also, how much of the foreskin is removed? A little bit? Most of it? All of it, right down to the base of the head? Or what?

The service that you provide is very informative. Thank you for it. When I have sex with my girlfriend and I thrust my penis deep into her body, she says that she can feel it hit something hard inside her body. I can't feel it hit anything. She is very curious to know what it is that I am hitting. Could you shed some light on this issue?

I have what appears to be scar tissue in the form of a straight line all the way down my penis, over my testicles and ends after that. Is this unusual for a guy? I am circumcised. Is this scar tissue from that or some strange webbing from birth?

Is it true that a woman can have multiple orgasms?

My new girlfriend and I had sex for the first time this weekend. Later in the evening, she was curious about something... "Where is that thing going???" she asked. She mentioned that full insertion was painful and she wanted to know what I was hitting, and "how far does it go?" Being admittedly a bit rusty on my knowledge of the anatomy of the female body, I told her that I thought it went no further than the "uvula" (whatever that is), but that I would do a little research, maybe see what I could get off the Net and get back to her.