What is PMS?
PMS (premenstrual syndrome) is a group of emotional and physical symptoms that show up in the days before your period and ease within a few days of it starting. Common ones are irritability, mood swings, sadness, bloating, sore breasts, tiredness and cravings. Over 90% of people who menstruate notice some premenstrual symptoms; for a smaller group they disrupt daily life.
What PMS stands for and when it happens
PMS stands for premenstrual syndrome. It happens in the luteal phase, the time between ovulation and your period, usually in the last 5 to 10 days. The key feature is the pattern: symptoms come before your period, fade within about four days of bleeding starting, and you feel more like yourself for at least a week afterwards.
What causes PMS?
PMS is linked to the rise and fall of estrogen and progesterone after ovulation. People with PMS don't usually have abnormal hormone levels. Instead, their brains seem more sensitive to the normal changes, which affect serotonin and GABA, the chemical messengers that steady mood, sleep and appetite. That's why PMS stops during pregnancy and after menopause, when the cycle stops.
Stress, poor sleep, alcohol, a lot of caffeine and low physical activity don't cause PMS, but they can make it feel worse. Read more in what causes PMS.
How common is PMS?
| Level | How many people | What it means |
|---|---|---|
| Some premenstrual symptoms | Over 90% | Noticeable but usually manageable changes |
| PMS symptoms at some point in life | Up to 3 in 4 | Symptoms that come and go over the years |
| Severe PMS | About 5 to 8% | Symptoms that substantially affect daily life |
| PMDD | Under 5% to about 8%, depending on the study | Mood symptoms severe enough to disrupt life every cycle |
PMS often feels strongest in your 30s and can get worse in your late 30s and 40s as you approach perimenopause. See the full PMS symptoms list, and PMS vs PMDD if yours feels severe.
What helps PMS
- Regular aerobic exercise, especially in the two weeks before your period
- Steady sleep and regular meals with complex carbs
- Less salt, caffeine and alcohol in the second half of your cycle
- Calcium: in a trial, 1,200 mg a day reduced PMS symptoms by 48% vs 30% on placebo
- Painkillers like ibuprofen for cramps, headaches and breast pain
- Seeing it coming: knowing which days are likely to be harder lets you plan and be kinder to yourself
- Treatment from a doctor if it's affecting your life: CBT, some hormonal contraceptives or SSRIs
When to see a doctor
See a doctor if PMS disrupts work, school or relationships, if you feel hopeless or out of control before your period, or if symptoms don't ease once bleeding starts. If you ever have thoughts of harming yourself, call your local emergency number now, or in the US call or text 988. In the UK, Samaritans are on 116 123.
Frequently asked questions
Is PMS real?
Yes. It's recognized by ACOG, the NHS and other health bodies, and the link with the menstrual cycle is well studied. See is PMS real.
Does everyone get PMS?
No. Most people notice some premenstrual changes, but not everyone has PMS that affects their life. See do all women get PMS.
How long does PMS last?
Usually 5 to 10 days before your period, easing within about four days of bleeding. See how long does PMS last.
Can men tell when you have PMS?
Some partners notice changes in mood or energy. Sharing a heads-up can help. See can men tell PMS.
Sources
- Office on Women's Health: Premenstrual syndrome (PMS)
- ACOG: Premenstrual Syndrome (PMS) FAQ
- NHS: PMS (premenstrual syndrome)
- Yonkers KA, O'Brien PMS, Eriksson E. Premenstrual syndrome. The Lancet (2008)
This page is for information only and isn鈥檛 medical advice. If something worries you, please talk to a doctor.
Keep reading
What are the most common PMS symptoms?PMS symptoms: the full list of emotional and physical signs, from irritability and crying to bloating and cravings, when they start, and when to get help.PMS mood swings: why they happen and what actually helpsTeary, snappy or anxious before your period? Why PMS mood swings happen in the luteal phase, what helps, and when it might be PMDD instead.
PMS vs PMDD: what's the difference?PMS vs PMDD side by side: symptoms, severity, how common each is, how they're diagnosed and treated, and how to tell which one fits what you feel.
PMS test: do my symptoms follow my cycle?Free PMS test: rate 11 common premenstrual symptoms and see whether yours look like mild PMS, typical PMS or something worth raising with a doctor.When does PMS start?When does PMS start? Usually 5 to 10 days before your period, after ovulation. How to work out your start day and spot your first warning signs.Luteal phase: why feelings get louderWhat the luteal phase is, how long it lasts, why progesterone rises and falls, and the common symptoms: PMS, cravings, low energy and mood changes.