PMS: what it means, symptoms and what helps

What does PMS mean?

PMS stands for premenstrual syndrome. It is the name for the physical and emotional symptoms that can appear in the run-up to a period and fade once it starts. Most women who have periods notice some premenstrual symptoms at some point. For most, they are mild and manageable; for a smaller number – around 2 to 4 in 100 – they are severe enough to disrupt daily life.

You may also see the terms PMT (premenstrual tension, an older British name for the same thing) and PMDD, a much more severe condition explained below.

How many days before a period does PMS start?

PMS happens in the second half of the menstrual cycle, after ovulation – known as the luteal phase. Symptoms usually start anywhere from a few days to two weeks before your period, tend to be strongest in the last few days, and ease within a day or two of bleeding starting. By the end of your period they have usually gone.

That timing is the key to telling PMS apart from other conditions: symptoms that carry on throughout the month, including the week after your period, are unlikely to be PMS alone.

What are the symptoms of PMS?

Symptoms vary from person to person and from month to month, though most women find they settle into a pattern. The most common are:

What causes PMS?

The exact cause is not known. PMS is thought to be linked to the rise and fall of oestrogen and progesterone during the cycle. Hormone levels in women with PMS are usually normal; what seems to differ is how sensitive the brain is to those normal changes. Brain chemicals such as serotonin and GABA are thought to play a part. This is also why PMS does not happen during pregnancy or after menopause, when the monthly cycle stops.

What is the difference between PMS and PMDD?

Premenstrual dysphoric disorder (PMDD) is a separate, much more severe condition. The timing is the same as PMS, but the emotional symptoms are intense enough to seriously affect work, relationships and daily life. They can include severe depression, feelings of hopelessness, anxiety, anger and, in some cases, thoughts of suicide. PMDD has been linked to an unusual sensitivity to normal hormone changes and to inherited factors.

PMDD is a recognised medical condition that needs proper care, not just self-help. If you think you have it, see your GP and take a symptom diary covering at least two cycles. Treatment may include antidepressants, hormonal treatment or psychological therapy, and you may be referred to a specialist.

Can PMS get worse with age?

It can. Many women find PMS becomes more noticeable in their 30s and 40s. In perimenopause, hormone levels swing more widely and unpredictably, and cycles can become shorter, so premenstrual symptoms may become stronger or last longer for a while. Mood changes, breast tenderness and poor sleep in your 40s can be a mix of PMS and early perimenopausal symptoms.

PMS ends at menopause, when periods stop. If symptoms change suddenly or feel very different from before, it is worth talking to a GP to rule out other causes – see signs of hormonal imbalance.

What helps PMS naturally?

Lifestyle changes are the first step, and they work better when kept up through the whole month rather than only when symptoms appear:

• Exercise regularly – aerobic activity such as brisk walking, swimming or cycling can lift mood and ease physical symptoms.
• Get enough sleep, with regular bed and wake times.
• Eat regular, balanced meals – smaller meals every 2 to 3 hours can help keep energy and mood steadier.
• Cut back on alcohol and caffeine, especially in the second half of your cycle.
• Don’t smoke.
• Reduce stress with yoga, meditation or breathing exercises.
• Use painkillers such as ibuprofen or paracetamol for cramps and headaches if needed.
• Track your symptoms in a diary or app for at least two cycles, so you and your GP can see the pattern.

Various complementary therapies and supplements are sold for PMS, but the NHS notes there is not much evidence that they work. If you are thinking of trying one, check with a GP or pharmacist first, especially if you take other medicines.

What treatments can a GP offer for PMS?

See a GP if lifestyle changes have not helped or your symptoms are affecting your daily life. Treatment is decided with your doctor and may include:

• Hormonal treatment, such as some types of combined contraceptive pill, which smooth out the hormone changes of the cycle.
• Cognitive behavioural therapy (CBT), a talking therapy that can help with mood and coping.
• Antidepressants (SSRIs), which can be taken all month or only in the second half of the cycle.

If these do not help, you may be referred to a gynaecologist or another specialist.