Why PMS Gives You Insomnia
Many women don’t need to look at a calendar or open an app to know when their period is approaching, thanks to tell-tale signs like bloating breast tenderness, and moodiness. While these are some of the most well-known symptoms of premenstrual syndrome (PMS), they are hardly the only ones. Also on the list: sleep problems.
For some women, the problem at this point in the cycle is not insomnia. Instead, they don’t feel rested after sleeping, or they need more sleep than usual to feel well-rested. And many say they feel more tired during the day.
Women who have other PMS symptoms are more likely to have trouble sleeping. And if their PMS is severe, especially if it affects their mood, they are “more prone to insomnia as well as sleepiness during the day,” says sleep physiologist Fiona Baker, Ph.D. She directs the Human Sleep Research Program at the nonprofit SRI International Health Sciences Center.
Women with the premenstrual dysphoric disorder (PMDD), which is similar to PMS but causes more anxiety or depression in the week or two leading up to their period, have the worst sleep problems as they approach “that time of the month.” Up to 70% of women with PMDD have symptoms of insomnia before their period.
The link between sleep and PMS
Why do sleep problems and PMS often overlap? “This is the million-dollar question,” Nowakowski says. “It’s multifaceted.”
The simplest explanation is that common PMS symptom such as bloating, breast tenderness, and pelvic or muscle pain may keep you awake. Feelings of depression, anger, anxiety, or irritability—also common PMS symptoms—can easily ruin a good night’s rest.
Mood and sleep are very closely related. If you are stressed or depressed, you are more likely to have trouble sleeping. But a poor night’s sleep can also ruin your mood the next day.
In addition, many women appear perfectly “normal” in sleep studies, Baker says, but still have trouble sleeping before their period.
It’s real. “We never want to imply that it’s all in your head,” Baker says. “It’s more than what we measure [in the lab] doesn’t really understand how anyone feels.”
How hormones can affect sleep
If you have sleep changes before your period, chances are that the change in hormone levels has something to do with it.
On average, the cycle lasts from 25 to 36 days. Day 1 is the day your period starts. Around the middle of your cycle, ovulation occurs: the ovary releases an egg. After about 5 to 7 days, estrogen and progesterone levels peak and then begin to decline (unless you’re pregnant).
Progesterone stays higher a little longer than estrogen. So as your period approaches—from 2 weeks to a few days—you reach a point where progesterone exceeds estrogen levels. This hormonal shift that occurs at the end of a cycle can affect your sleep as you approach your next period.
Experts believe that this change in levels rather than low or high levels of estrogen or progesterone, which have the greatest potential to ruin sleep.
“The worst time for sleep and mood, even in people without severe PMS, is 4 to 5 days before your period during the first two days of your period,” Nowakowski says. For women who are more sensitive to hormonal shifts, the impact on sleep can be significant.
What is still unknown
No one knows exactly how changing hormone levels at the end of a cycle affects sleep. But experts know that there are estrogen and progesterone receptors in the brain, including in areas involved in managing sleep.
“Higher doses of progesterone cause drowsiness,” Baker says, “and that’s one reason women with PMS may feel sleepier during the day.”
During the later part of your cycle, levels of the brain’s chemical serotonin also change. One theory is that a lack of serotonin before menstruation contributes to PMS symptoms such as premenstrual depression and food cravings, as well as fatigue and trouble sleeping.
Body temperature can also play a role. It rises slightly after ovulation and remains elevated until you start menstruating again (unless you are pregnant). Because body temperature naturally drops slightly before and during sleep, running a little hotter than usual can make it difficult to fall asleep or get a good night’s sleep.
Temperature can also affect your circadian rhythms (your body clock), Baker says. Some research shows that women with PMDD produce less melatonin, a hormone that helps tell your body that it’s time to rest.
How to sleep better before your period
If you often have trouble sleeping before your period, there are things you can do to feel better overall.
Cut down on salt, sugar, caffeine, and alcohol. Don’t give in to cravings for chips or candy. Nowakowski recommends cutting back on salt and sugar (which cause inflammation) to reduce bloating. Instead, try to eat more protein and complex carbohydrates. She also suggests cutting down on caffeine (a stimulant) and alcohol (a depressant).
Address your stress. Stress is a notorious sleep destroyer. Practicing stress management—for example, through exercise, meditation, or deep breathing—can help.
Talk to your doctor. If you have severe PMS – you may think you may have PMDD – talk to your doctor. Depending on your symptoms, hormonal contraceptives or antidepressants can help both your mood and sleep problems.
Consider therapy. If sleep is your main concern — and following basic sleep hygiene measures, such as going to bed and waking up at the same time every day, doesn’t help — you might also consider CBT-I, a type of cognitive-behavioral therapy that focuses on changing thoughts and behaviors that cause sleep problems.