PMDD / PMS Isn't One Thing: The Three Patterns Behind Premenstrual Symptoms

I hear a version of this sentence in clinic most weeks: "I'm fine, and then I'm not fine, and I can't work out why it's different every month."

For years the working theory on PMS has been fairly blunt: oestrogen and progesterone go up and down, and some women feel it more than others. True, as far as it goes. But it doesn't explain why one patient's symptoms vanish the second her period starts, while another's low mood drags on for days after bleeding begins. It doesn't explain the woman who swears she's "fine all month" except for a reckless week around ovulation she's never once connected to her cycle. And it doesn't explain why the same woman can sail through one cycle and be flattened by the next.

New research on premenstrual dysphoric disorder (PMDD) offers a better explanation, and it's one I think every woman with a menstrual cycle should hear, whether her symptoms are mild or disabling.

It isn't really about how much oestrogen or progesterone you have. It's about how sensitively your brain responds to the normal rise and fall of those hormones.

Researchers call this DASH: Dimensional Affective Sensitivity to Hormones. Put simply, some brains read the same hormonal weather report very differently to others, and that sensitivity shows up as three distinct patterns, each on its own timetable, each needing a different response.

Pattern one: the irritability window (classic PMDD)

This is the one most people picture when they hear "PMS": the short fuse, the sudden tears, the sense that your own skin feels too tight. It tends to start a week to ten days before your period, builds through late luteal phase, and then lifts almost overnight once bleeding starts.

The hormone thought to be responsible, allopregnanolone (a calming by-product of progesterone), isn't actually lower in women with this pattern. It rises exactly as it should. The problem is that in some women, the receptor it's supposed to calm responds the opposite way. Instead of settling the nervous system, it winds it up. Think of it like a dimmer switch that's wired backwards: turn it up expecting things to soften, and instead everything gets brighter and louder.

In TCM terms, this maps closely to Liver Qi Stagnation with rising heat: pent-up energy with nowhere to go, presenting as irritability and a short fuse. Acupuncture alongside nutrition works very well to settle this feeling and bring back a sense of calm.

What helps: saffron, evening primrose oil, PEA and ginkgo biloba , and a practitioner can test the relevant genetic pathways if this pattern is severe or hasn't responded to the basics. This is also where an SSRI, if you and your GP decide it's the right tool, tends to work unusually fast for PMDD specifically, often within days rather than the usual weeks, because it's recalibrating a system that's already primed rather than treating a deficiency.

Pattern two: the low that doesn't lift

This one confuses people the most, because it breaks the "rule" that PMS ends when your period starts. Instead it often begins in late luteal phase and drifts on into the first days of the new cycle: flat mood, apathy, brain fog, struggling to find the right word mid-sentence. If that list sounds like perimenopause, you're not imagining it. The mechanism is the same.

Oestradiol is the main accelerator for serotonin and dopamine production. When it falls (which it does naturally, and further, as the next cycle's low point approaches), that accelerator eases right off. No wonder the joy goes with it.

What helps: this is where I think about cushioning that dip rather than trying to override it with soy isoflavones. Soy isoflavones specifically aren't appropriate for the first several years after a young woman starts her periods.

Pattern three: the one nobody's watching for

This is the pattern I find most interesting, because almost nobody connects it to their cycle at all. It happens around ovulation, days eleven to fourteen, not premenstrually, which is exactly why it gets missed. Increased impulsivity, a pull towards risk, a restless "chasing something" feeling, sometimes more alcohol than usual, sometimes decisions you wouldn't normally make.

The oestrogen surge around ovulation does heighten your brain's reward response. It's dopamine doing exactly what oestrogen tells it to. One detail worth knowing: research shows alcohol's disinhibiting effect is nearly doubled during this window compared to other points in your cycle.

What helps: mostly, awareness. If you know this is a recurring five-day pattern rather than a personality trait, you can plan around it, build in a bit more structure, and be kinder to yourself about it afterwards.

Why this reframe matters

None of these three patterns are about being "too sensitive" or not coping well enough. They're about a nervous system responding, predictably and mechanically, to the biggest hormonal swing most bodies go through every month. Once you know which window you're in, you stop treating every bad mood as a mystery and start treating it as data.

A few places I always start with clients working through this:

• Rule out anaemia first. Low iron limits your body's ability to make neurotransmitters at all, and no amount of saffron or SSRIs will fix PMS built on top of undiagnosed iron deficiency.

• Track by pattern, not just by "PMS." A simple cycle diary that notes mood, timing and what phase you're in for two or three months tells you far more than any single blood test.

• Match the support to the window. What settles irritability in the ten days before your period isn't what lifts a flat mood after it, and it isn't what you need around ovulation either.

If any of these three patterns sounds familiar and you'd like help working out which one (or ones) you're dealing with, that's exactly the kind of thing we untangle together in clinic.

Book a consultation at valehealth.co.uk/book and let's work out what your cycle is telling you.