PMS (premenstrual syndrome) is a set of physical and emotional symptoms that show up in the second half of your cycle, after ovulation, and clear away quickly once your period starts. Sore breasts, a short fuse, low mood, cramps, tiredness. It is common, it is real, and there are sensible things you can do about it. Here is the honest version, without the hype.
What PMS actually is
PMS stands for premenstrual syndrome. It is tied to your menstrual cycle: symptoms build in the second half, after ovulation and in the run-up to your period, then fade fast once bleeding begins. That quick clearing is the tell-tale sign.
It is common too. Depending on the study you look at, somewhere around 10 to 20 percent of women get these symptoms. That is a very large group, so if this is you, you are far from alone.
The symptoms
PMS is not a fixed checklist, it is a spectrum. One woman gets a mild day or two; another feels it for half the month. The symptoms roughly split into two camps.
Physical:
- Tender, sore breasts
- Cramps, and sometimes gut trouble
- Headaches (worth noting: this is different from a hormone-driven migraine)
- Sore muscles and slower recovery after a workout
- Tiredness and fluid retention
Mental and emotional:
- Mood swings, sometimes within a few hours
- Low mood
- Irritability and a short fuse, one of the most common complaints of all
That irritability can put real strain on relationships. A lot of women recognise the one moment each month where everything feels like too much, while at the same time knowing their period is on the way.
PMS vs PMDD
PMDD (premenstrual dysphoric disorder) is often described as a more severe version of PMS, with a few extra criteria. It affects roughly 3 to 8 percent of women.
With PMDD the symptoms are severe enough to be treated almost as an illness, and they are often mainly psychological. In the podcast, endocrinologist Diederik describes seeing women in his clinic who felt close to suicidal in the last days before their period, and whose only anchor was knowing it would lift again in a few days. Some cannot work for a week, and for some it starts around ovulation, so they carry it for half the month. As with PMS, the fast clearing once the period starts is still the hallmark.
Why it happens
The word “syndrome” gives it away: it is a cluster of symptoms whose exact cause we do not fully understand. But a few things are clear.
Strikingly, there is no big hormonal difference between women who get PMS and women who do not. The current thinking is that the body reacts abnormally to perfectly normal hormone shifts.
After ovulation your body makes progesterone alongside oestrogen. Progesterone rises first and then falls again, and it seems to be those changes, possibly the speed at which progesterone drops, that play a key role. Brain chemistry likely matters too, including serotonin and the breakdown products of progesterone. In other words, your hormones are doing exactly what they are meant to do to keep you fertile; it is the brain that is over-sensitive to it. As Diederik puts it, it is a bit like a man feeling ill from a healthy testosterone level.
What helps: lifestyle, food and movement
For mild to moderate symptoms, lifestyle is the first port of call. Enough sleep, varied food, regular exercise and keeping stress in check can all help.
It probably works in two ways. A healthy lifestyle can nudge your hormone balance in a better direction. But maybe more important is resilience: if you sleep better, handle stress better and make deliberate choices, you can carry and manage the symptoms more easily.
Be realistic, though. A healthy lifestyle does not scrub PMS away completely, and an unhealthy one is usually not the cause either. What it can do, for a lot of women, is make the difference between being floored by it and being able to fit it into daily life.
On supplements like magnesium, vitamin B6 or chasteberry (vitex agnus-castus), there is some evidence, but it comes from small, low-quality studies. The effect is often statistically detectable yet clinically small. There is no harm in trying, but do not expect miracles, and there is no need to spend a fortune. A basic magnesium supplement in the UK costs only a few pounds.
When to see a doctor, and the treatments that exist
Whether you want treatment is largely your call. It comes down to how much it affects you and how far it reaches into your life, work and relationships. If you feel stuck, a chat with your GP is a low-pressure and sensible first step.
If lifestyle is not enough, there are medical options. A blood test can be useful to rule something else out, such as a thyroid problem. There is no test that proves PMS itself.
The two main routes are:
- SSRIs (better known as antidepressants). The name puts people off, but the research suggests they often work well, and fairly quickly. You can even take them only in the second half of your cycle. When low mood is the main problem, they tend to do better on average than hormonal options.
- A hormonal approach. The contraceptive pill has the most evidence and suppresses the ovaries so the swings drop away. The downside is a small increased risk of blood clots and breast cancer. An alternative is body-identical hormones, which smooth the swings without those same risks.
None of these treatments fixes the root cause, because we do not understand it well. The aim is simpler: a solid reduction in symptoms so you feel better and can just get on with things. Route A suits one person, route B suits another. The message from the episode is a hopeful one: you do not always have to just push through it, there are ways to deal with it better.
Frequently asked questions
How long does PMS last?
PMS sits in the second half of your cycle, from after ovulation up to your period. For some women that is a day or two; for others it starts around ovulation and lasts almost half the month. The tell-tale sign is that the symptoms clear quickly once your period begins.
What is the difference between PMS and being pregnant?
Early pregnancy signs like sore breasts, tiredness and mood swings can look a lot like PMS. The key difference: with PMS the symptoms fade once your period starts. If your period does not arrive and the symptoms continue, take a pregnancy test or speak to your GP.
What helps with PMS?
Start with lifestyle: good sleep, varied food, regular exercise and less stress. That can nudge your hormone balance and, above all, build your resilience. If that is not enough, there are medical options such as SSRIs or a hormonal approach (the pill or body-identical hormones). What works best differs from person to person, so discuss it with your doctor.
PMS and exercise: can I keep training?
Regular exercise is actually recommended and may ease PMS symptoms. That said, in this phase you might notice more muscle soreness and slower recovery after a hard workout. Listen to your body and dial the intensity down when you need to, rather than stopping altogether.
What is the difference between PMS and PMDD?
PMDD (premenstrual dysphoric disorder) is a more severe form of PMS with a few extra criteria, affecting roughly 3 to 8 percent of women. The symptoms are often mainly psychological and severe enough to disrupt work and daily life. As with PMS, the quick clearing once your period starts is still the hallmark. If your premenstrual symptoms feel overwhelming, speak to your GP.
Do supplements like magnesium or vitamin B6 work for PMS?
There is some evidence for magnesium, vitamin B6 and chasteberry, but it comes from small, low-quality studies and the effect tends to be small in real terms. They are cheap and low-risk to try, so there is no harm in it, but do not expect them to solve the problem on their own.
