Real reason you should always go to the loo after having sex

There are some pieces of health-based advice many of us simply grew up with and never thought to question.

Whether you were told to get '10,000' steps in a day with no questions asked, or still have the 'five-a-day' narrative cemented in our brains whenever we do the food shop - it's clear there are just some pearls of wisdom we were all told to follow despite maybe not knowing the immediate benefit of doing so.

And a major one I'm sure many of us have heard from our mothers and seen on telly is the cardinal rule 101 of being a woman: always pee after having sex.

But what's the actual science behind this, and what happens if you don't?

There's an extremely important reason you should ALWAYS pee after having sex (Studio4 / Getty Images)

Now, there are a few reasons for this, but the biggest has got to be to reduce your chances of contracting a urinary tract infection - or UTI for short.

The NHS explains that UTIs affect your urinary tract, including your bladder, urethra or kidneys (kidney infection).

And, while UTIs may be treated with antibiotics if they don't go away on their own, they've got some pretty grim symptoms you seriously do not want to experience.

Symptoms may include:

• pain or a burning sensation when peeing (dysuria)
• needing to pee more often than usual
• needing to pee more often than usual during the night (nocturia)
• needing to pee suddenly or more urgently than usual
• pee that looks cloudy
• blood in your pee
• lower tummy pain or pain in your back, just under the ribs
• a high temperature, or feeling hot and shivery
• a very low temperature below 36C

Peeing after sex significantly reduces your risk of contracting a UTI (Antonio Hugo Photo / Getty Images)

But what has sex got to do with all that?

Well, during sex, bacteria can enter your urethra, which, in turn, raises your chances of getting an infection.

That's why it's super important to always pee after sex, as peeing flushes out the germs.

People with vaginas are far more prone to getting UTIs as their urethras, a tube-like organ that helps pass urine out of the bladder, are shorter (about 2.5 to 4cm than people with penises (about 15 to 20cm) meaning that bacteria has to travel a shorter distance to enter the bladder.

Flo, a period and ovulation tracker app, advises: "It’s always a good idea to pee after sex, particularly for women.

"Because women’s urethras are shorter than men’s, bacteria can enter easily and cause a urinary tract infection. When you pee after sex, it may help flush out bacteria from the urethra.

"This helps prevent UTIs."

Keep that in mind this Valentine's Day, ladies!