Why does sex cause UTI's?

I'm prone to UTIs after intercourse. What sex positions are less likely to cause UTIs? (NSFW) I am susceptible to urinary tract infections after intercourse. No other sexual activity causes this problem for me. I am female. My boyfriend and I take a...

My boyfriend and I had anal sex and oral (vaginal) sex (unprotected) a month ago which resulted in him getting a UTI. His symptoms began with a very bad sore throat, a kind he had never experienced before and a few days later a burning sensation when...

My boyfriend and I had anal sex and oral (vaginal) sex (unprotected) a month ago which resulted in him getting a UTI. His symptoms began with a very bad sore throat, a kind he had never experienced before and a few days later a burning sensation when...

during and after sex so me and my partner decided to stop. It's been a week since I've had sex but I'm still having vaginal pain. All of this started once I got on the nuva ring, could it be the cause? I have gotten treated for the UTIs, had a pelvic...

I love my husband, he loves me. But something has been strange with him in the past 6 months. We don't have sex. And the only 2 times we've had it in the past 6 months, he's just rolled on me then rolled off. He's capable of so much more. The lack of...

I have gotten 2 UTIs within the past 2-3 months...I was just wondering what causes them and why I've gotten them so much. I got on birth control about 4 months ago and started having sex about 2 1/2 months ago. could those things cause it? please help...

After every time my partner and I have sex I get painful contractions that last for hours. I've tried changing positions, walking around, I even carry on with my day and go do the groceries etc nothing helps them! Does anyone else get this or know why...