I am a seemingly healthy 18-year-old woman and I was having great sex with my fiance until a problem developed a month ago: When he first penetrates me it feels like I have a cut in my vagina and it opens up when I have sex. It hurts and burns. About five minutes after we start, the pain is gone and it feels great. I have been to the doctor and he said he couldn't find anything wrong, so I don't know what to do.

My first suggestion is that you get a second opinion from a gynecologist to make sure there is nothing medically wrong. From the perspective of sex therapy, maybe you haven't been lubricating as much before intercourse because there's been less foreplay or you have been preoccupied with other thingsnd. Certainly you shouldn't engage in any penetration that involves pain.

A quick solution is to use a lubricant. But since this is a new problem, you must also find out the cause. Either your doctor will be able to locate the source of the problem or you will have to discover what else might be happening here. If penetration is occurring too early because you are worried that it will all be over in five minutes, you must work on that with your boyfriend. If some other worry is making you lose interest in sex and not lubricate, then you should try to get help to deal with this problem.