Trouble Sleeping Before Your Period?What Studies Show

If your sleep falls apart a few nights before your period every month, the research suggests you’re not imagining it, though not every woman follows the same pattern.

Worse sleep, same hours

In Johannesburg, 26 healthy young women with confirmed ovulation rated their sleep every day for a month.¹

• Sleep quality felt worse over the 3 days before and 4 days during their period.¹
• Total sleep, time to fall asleep and night wakings didn’t change.¹

A US diary study of 32 women over two cycles found it took longer to fall asleep and sleep was less efficient in the second half of the cycle, after ovulation.² That happened across the group, not just in women with bad PMS.²

Three patterns

A larger study tracked 213 women daily for two cycles and found three groups:³

Pattern	What it looked like
Around the period	Sleep trouble rose just before and during bleeding3
Mid-cycle	Sleep trouble rose around the middle of the cycle3
No change	Sleep stayed about the same all month3

On days with more mood, energy or physical symptoms, sleep was harder.³

Who’s most affected

A 2023 review found poorer sleep before and during periods is common in women with premenstrual symptoms or painful cramps.⁴ In women without those symptoms, lab recordings of sleep stay mostly steady across the cycle.⁴ Women with worse PMS also reported more daytime sleepiness before their period.²

All of these studies were small and in younger women, so they can’t say exactly how this plays out in your forties.

What to do

1. Track two cycles. Note cycle day, sleep quality, pain and mood each morning. A pattern tied to cycle days points somewhere different than random bad nights.¹⁴
2. Treat the cramps if pain wakes you; see best painkillers for period cramps.
3. Plan heavy nights so you’re not waking to check for leaks.
4. Ask about PMS or PMDD if mood and sleep crash together every month; see what PMDD is.

The review’s authors say cycle phase should be part of how women’s sleep complaints are assessed.⁴

Try: “My sleep is fine most of the month, but for about five nights before my period I lie awake and feel wrecked the next day. I’ve tracked it for two cycles. What could help?”

Period, Handled covers night planning in Chapter 10, “Work, Travel, Gym, Bed.” Its Period Scorecard gives each bleeding day a line, with whether any night needed a change, a pain score and a tiredness score, so a run of bad nights shows up against your cycle days. See the book.