Your older sister. Your best friend. Your cool aunt. If you have a vagina, one of them has probably shaken a finger at you and forewarned, “always pee after sex”. But why do our older, wiser sexual gurus always pledge their allegiance to the post-coital whizz? What does urinating after sex actually achieve? 

Does peeing after sex prevent UTIs? 

Yes, peeing after sex can help prevent you from getting a urinary tract infection (UTI). 

While it’s not a foolproof method, many people with vaginas find it helpful, and doctors say it makes anatomical sense. 

UTIs occur when foreign bacteria enter the urethra and travel to the bladder, causing infection (which, as anyone who’s had a UTI will tell you, is no fun at all). If you have a vagina, the length of your urethra is shorter than in a person with a penis, meaning bacteria don’t have to travel far to reach the rest of your urinary tract. Also, the urethra is a pretty close neighbour of the vagina and the anus, making it easy for bacteria from either place to end up there. 

Peeing after sex helps to flush out nasty bacteria from the urethra before they can travel to the bladder and cause an infection. 

When should you pee after sex? 

There’s no hard and fast rule for when you should pee after sex to help prevent UTIs. Shooting off straight away means you can get back to bed and nod off in your partner’s arms sooner, but there’s no harm in lingering for a few minutes in the post-coital glow. 

What if I don’t need to pee? 

If you don’t have to go there’s no need to force it. Forcing out a sad little trickle won’t effectively flush out your urethra anyway. Enjoy the cuddle time or nod off for a while if that feels right. That said, it pays to be well-hydrated enough to be peeing regularly anyway, so make sure you’re getting those 2 to 3 litres in. 

Can peeing after sex prevent pregnancy? 

Urinating won’t prevent pregnancy, even if you go mere seconds after ejaculate is released. Sperm travel to the fallopian tubes (where conception happens) through the vagina, so urinating out of your urethra won’t interfere with their journey.

If you’re trying to get pregnant, some experts recommend waiting a few minutes before getting up after sex, to help any slowpoke sperm on their way. Most of the effective swimmers, however, will make their way to the fallopian tubes (where conception occurs) in mere minutes, with or without you lying down, so trotting off to the toilet after sex shouldn’t hurt your chances. 

Can peeing after sex prevent STIs? 

Nope. Peeing after sex may help flush out UTI-causing bacteria, but it won’t prevent you from contracting a sexually transmitted infection (STI). The bacteria that cause STIs enter the body in a different way, via its mucus membranes, so peeing won’t affect the absorption process. The best way to prevent contracting STIs is by using barrier protection (condoms or diaphragms). 

So, is it really necessary to pee after sex? 

If you have a vagina, it’s always a good idea to urinate after receiving oral or penetrative sex, especially if you’re prone to UTIs. That said, if you normally don’t go and experience no issues, there’s no reason to start now. Do what is comfortable for you and, as always, see your doctor if you have any burning concerns.