Picture this: after taking your time in a warm shower, you moisturise, chuck on your comfiest pyjamas, brush your teeth, go to the toilet and slide into bed.

The sheets are cold, but you quickly warm them up, wrapping yourself up in the doona like a human burrito. You pick up your phone and set your alarm for the morning. You might have a quick scroll on Instagram or pick up a book, chat with your partner or watch a video on Youtube. Once you’re finally ready to switch off, you roll over and close your eyes.

Then, it happens. That familiar dull surge down there. And not the one that means you might like to have an orgasm. No, you need to pee, again. Even though you literally just went.

In bedrooms and bathrooms around the country, women are dragging themselves out of their perfectly warm and cosy beds to go to the toilet because it simply must be the very last thing they do before going to sleep. The official terms for it are ‘nocturia’ or ‘frequent evening urination’.

I am one of these women and have been for years. I thought it was one of my cute little quirks. But after admitting my annoying evening habit in a meeting (trust me, it was relevant), a few of my colleagues said they do the same thing. So, as it turns out, I’m not special and neither is my nightly peeing habit.

But why do we do it? Night after night after night, why do we force ourselves to squeeze out two more drops on the loo, despite having squeezed out five drops 10, 15 or 20 minutes earlier?

The answer could be physical, but is more likely mental, as I found out after chatting about urine with a GP and a psychologist.

Here’s what they said about why you always have to pee right before bed, condensed into three factors.

Need help getting to sleep? Here are some tips to try tonight, post continues after video.

Why do I always need to pee right before bed?

1. The psychological reason (a.k.a. it’s all in your head).

Before you let Google convince you there’s something seriously wrong, Dr Ginni Mansberg said there’s a pretty easy way to figure out if you’re getting up to pee because you genuinely need to, or if your mind is telling you so.

“You can tell by the volume of pee whether the need to go was a function of the amount of fluid in your bladder stretching the bladder wall, signalling to the nerves inside the bladder wall you need to pee, or if it’s literally a psychological thing,” Dr Mansberg told Mamamia.

In other words: a strong stream = needed to pee, and a few drops = didn’t really need to pee.

Makes sense, but what doesn’t is: why anyone would make themselves get out of a warm bed to sit on a cold toilet seat if they didn’t actually need to?

According to Tahnee Schulz, psychologist and Head of Clinical at Lysn, it’s your brain’s way of helping you navigate your way through life. Stay with me.

“There’s a couple of different ways these patterns we create, like going to bathroom before bed, start to develop associations and then turn into habits we almost feel trapped in,” Schulz told Mamamia.

“The brain is constantly creating associations to help us get through life – it’s the same as the ritual of going to the toilet at night time. It may have initially been that you heard someone say it’s important to go to the toilet before bed, perhaps your mum said it, and it became a natural ritual of how you get ready for sleep. Those core behaviours happen in order for your brain to say, it’s time to go to bed.

“At the time when we first started those behaviours, there was some logic behind it and a purpose. For example, your mum might’ve started telling you to go to the toilet before bed during a bedwetting period when you were younger. But patterns are like muscles, and the more you work them out, the more demanding or dominant they become. It goes from I should to I must.”

Then, there are the people who are generally anxious or are living in high stress situations who may experience physiological changes in their bodies, like needing to pee all the time. For them, going to the toilet right before bed “can be an anxiety that you feel like you have to do these things to achieve an outcome. For example, I must pee right before bed or I won’t sleep well or I might wet the bed,” Schulz added.

Generally speaking, Dr Mansberg believes this issue is a psychological one for healthy women in their twenties and thirties. For women heading towards or who have been through menopause, there could be a physical reason for needing to pee.

2. The likely physical reason, poor bladder training.

Likely the biggest factor making you jump out of bed for the bathroom is your bladder control.

"Some people are excellent pee holders at night. These are people who can have a glass of water and a cup of tea before bed and still not need to pee, and are probably going to go into old age with a fantastic bladder. Others aren't as good in that space and they'll generally need to go more at night, or during the night," Dr Mansberg said.

"As women head towards menopause and after menopause, needing to pee a lot at night often comes packaged up with a bit of incontinence. Most women think of incontinence as being the type when you sneeze and your pelvic floor isn't what it used to be, that's called stress incontinence.

"The other type of bladder change that happens as we go through menopause that we don't talk about enough is urge incontinence, which is very small amounts of pee leaking out independent of running, jumping or any activity that increases pressure inside the pelvis. That has less to do with menopause, hormones or having delivered a baby, and more with being just one of those things."

While drinking fizzy drinks, sparkling water and caffeine can increase the urge and frequency of needing to pee, it can also come down to not having great control over your bladder and misinterpreting normal bladder cues.

"If you're the sort of person who jumps at every cue your bladder sends, including as you're drifting off to sleep, you're setting yourself up to have a problem later on in life. There's an argument for not responding to every cue your bladder sends you, especially when you know your bladder could not possibly be full because you just went... we don't have trial data that proves bladder training in your twenties in thirties will protect you later, but many experts think it will."

3. The less common physical reasons.

Not sure about either of the options we've discussed so far? Dr Mansberg suggested a few other physical causes for needing to pee before bed/at night time that are less likely, but worth checking out if it will give you peace of mind.

They are:

• Urine infections - "If you need to pee all the time, it's always a small amount and it burns and stings, it's a UTI. Ural is great but it doesn't treat a urine infection, you need antibiotics for that."
• Chlamydia - "Chlamydia often impacts on the lower urinary tract and can give off similar symptoms to a UTI. Most women won't experience symptoms, but you might experience urine symptoms so get tested if you have multiple sexual partners, or someone you're intimate with does."
• Pregnancy - "Pregnant women will pee more because of a higher blood volume so you've got a higher volume going through your kidneys, but I've personally never met a patient that found out they were pregnant because of peeing more."
• Drinking too much water - "If you are a healthy woman, there's a good chance you're waterboarding yourself and drinking way too much fluid. An average woman needs 2.1 litres of fluid in winter, unless you've done a workout, then you need a bit more. If you're drinking a lot of water at night, you will be peeing through the night."

If you're ever unsure about any of your symptoms, always speak to your GP.

What can you do about it?

Once you figure out why you're always getting up to pee before bed, then you can go about... not doing it anymore.

If you're going out of a habit or anxiousness, both Schulz and Dr Mansberg recommend sitting (well, technically lying) with the feeling of needing to pee to work towards breaking the habit. Be warned, you might find it a tad uncomfortable for a few weeks, but just as you formed the habit, you can break it.

You can also decrease your fluid intake at night, specifically avoiding caffeine, fizzy drinks and sparkling water.

Finally, some bladder retraining can help you remember what it actually feels like to need to pee - you can try this at work by not getting up every time you feel a twinge, instead waiting to see if the feeling subsides.

Just don't wait too long, OK?

Have you experienced this? What worked for you? Tell us in the comments.

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