We talk a lot about what periods do to our days. The cramps, the cravings, the brain fog. But what about what they do to our nights? For millions of women, the week of their period - and the days leading up to it - brings some of the worst sleep of the month. And if you're someone who trains, competes, or simply tries to live an active life, that lost sleep isn't just uncomfortable. It has real consequences for your body, your performance, and your recovery.

Here's why your period disrupts your sleep, and what you can actually do about it.

Why Periods and Sleep Don't Mix

1. Pain and Cramps

The most obvious culprit. Dysmenorrhoea - the clinical term for painful periods - affects up to 80% of women at some point in their lives, and for those living with conditions like endo, it's severe enough to disrupt daily function. At night, the discomfort of cramping in the lower abdomen, back pain, and headaches can make it extremely difficult to fall asleep, and impossible to stay there. Research confirms what most of us already know from experience: pain during menstruation is directly linked to poorer sleep quality.

2. Your Body Temperature Goes Haywire

Here's something that doesn't get talked about enough. In the lead-up to your period - during the luteal phase of your cycle - rising progesterone levels cause your core body temperature to increase by as much as 0.3°C to 0.7°C. That might not sound like much, but your body needs to lower its core temperature in order to fall and stay asleep. A warmer baseline makes that harder.

As your period actually arrives and progesterone drops, the hormonal shift can trigger night sweats and hot flushes - that maddening experience of feeling too hot, then too cold, then too hot again. It's not just uncomfortable; it's genuinely disruptive to the sleep architecture your body needs to properly recover.

3. Anxiety About Leaking

This one is underreported but incredibly common. Worrying about leaking through your protection - onto your sheets, your pyjamas, your mattress - is a real and legitimate source of sleep anxiety. Whether it's a conscious worry or a low-level background stress, that anxiety activates your nervous system and makes deep, restful sleep harder to achieve. Many women find themselves waking repeatedly to check or change their protection, disrupting the sleep cycles their body most needs. But NIXIs can help with that (more on that later!)

4. Hormonal Mood Disruption and Anxiety

The hormonal fluctuations of the menstrual cycle don't just affect your body - they affect your brain. In the days before and during a period, drops in oestrogen and progesterone can trigger heightened anxiety, low mood, and even disturbing or vivid dreams. Research shows that women with severe PMS more frequently report disturbing dreams, fatigue, and trouble concentrating - all of which compound into a cycle of poorer sleep quality. Women with irregular menstrual cycles have been found to have a two-fold higher risk of insomnia.

5. Bloating and Physical Discomfort

Beyond cramps, the general physical discomfort of bloating and water retention can make it difficult to find a comfortable sleeping position. The kind of unconscious shifting and waking that comes from physical unease adds up across a night and chips away at the deep sleep your body is trying to get.

Why Sleep Matters So Much - Especially If You're Active

Sleep isn't passive. It's arguably the most powerful recovery tool available to any woman who exercises - whether you're a professional athlete or someone who trains a few times a week because it makes you feel good.

During sleep, your body repairs muscle tissue broken down during training, regulates the hormones that control energy and mood, consolidates the motor skills and movement patterns you've been practising, and strengthens your immune system. Research across elite sport has found that sleep disturbances affect between 50 and 78% of elite athletes - and the consequences are significant. Poor sleep has been shown to impair sport-specific skill execution, coordination, mood, and both aerobic and anaerobic performance.

For female athletes specifically, the picture is even more complex. Emerging research highlights that women may be more vulnerable to the performance impacts of disrupted sleep than men - yet sleep science in sport has historically focused almost exclusively on male athletes. The result is that many active women are simply not getting the recovery support they need during one of the most physiologically demanding times of their month.

If your period is costing you two or three nights of quality sleep every month, that's a meaningful hit to your recovery, your training adaptations, and how you feel in your body.

How to Sleep Better During Your Period

Keep Your Bedroom Cool

Given the temperature disruption that comes with your cycle, keeping your sleep environment as cool as possible gives your body the best chance of regulating itself. Aim for a room temperature of around 16–18°C, use breathable, natural-fibre bedding, and consider a lighter duvet during the days around your period.

Use Heat Strategically - Before Bed

A hot water bottle on your lower abdomen can relieve cramps and actually help prepare your body for sleep by drawing blood flow to the surface and helping you feel ready to wind down. Use heat in the hour before bed, then cool the room once you're ready to sleep.

Wind Down Your Nervous System

Anxiety and hormonal mood shifts make it harder to switch off at night. Build a wind-down routine that actively calms your nervous system: a warm bath or shower, gentle movement or stretching, limiting screens for the hour before bed, and avoiding caffeine after midday. Magnesium - which many women are deficient in - has been shown to support both sleep quality and menstrual symptom relief, and is worth discussing with your GP.

Track Your Cycle and Work With It

One of the best things any active woman can do is track her cycle so she can anticipate the harder nights and plan around them. If you know the week before your period tends to be your worst for sleep, you can protect that week - schedule fewer evening commitments, prioritise earlier bedtimes, and be gentler with your training expectations.

Wear Protection You Can Actually Trust

If worrying about leaking through the night is keeping you awake - or waking you up - the solution is to remove that worry entirely. The NIXI Body Yasmin Sleep Short is designed precisely for this. A boxer-style leakproof short with super absorbent (holding 4-5 tampons worth of blood) overnight protection, the Yasmin is built for heavy flow and bladder leaks - so you can go to sleep knowing you're genuinely covered. No midnight checks, no anxious half-waking, no ruined sheets. Just the deep, uninterrupted sleep your body is asking for. Because the best thing you can do for your period - and your performance - is rest.

Gentle Movement Earlier in the Day

Exercise is one of the best natural remedies for period symptoms - it releases endorphins, eases cramping, and reduces stress. But timing matters. High-intensity training late in the evening raises your core temperature and cortisol levels, which is the opposite of what you need before sleep. On the harder days of your cycle, opt for gentler movement - yoga, walking, swimming - and keep intense sessions to the morning or early afternoon.

The Bottom Line

Your period disrupting your sleep isn't weakness - it's biology. But it doesn't have to be inevitable. Understanding why it happens puts you in a far better position to address it, and with the right environment, habits, and protection in place, restful nights during your period are absolutely possible.

For active women, especially, those nights matter enormously. Sleep is where the training happens - where your muscles rebuild, your skills consolidate, and your body prepares to go again. Protecting your sleep during your period isn't just about comfort. It's about performance.

NIXI Body makes leakproof performance underwear for active women and girls. The Yasmin Sleep Short offers super absorbent overnight protection for periods and bladder leaks - so nothing gets in the way of your rest.