Evidence-led support for when migraine, mood, pain and everything else changes with your menstrual cycle.
Free. Track the pattern, understand the evidence, prepare for better care.
You are not failing. You are living in a body that changes across the cycle, and no one taught you how to track it or talk about it.
If your migraines, mood, focus, gut, pain or dizziness get harder at certain points in your cycle, that can be a pattern, not a personal failing. And if your medication seems to stop working the week before your period, your treatment may not be failing either. Your condition may be following your cycle, and nobody told you to look.
Most people's conditions don't change with their cycle. For some, the cycle is a real, recognised trigger. Pinkerton et al., 2010 · Am J Obstet Gynecol · doi (opens in a new tab)
Rate how your day actually was before you look at where you are in your cycle.
Knowing your cycle day can shape what you notice. Keeping your ratings and your dates apart makes your record harder to dismiss, by anyone, including you.
Emerging evidence
"Premenstrual symptoms: a reinterpretation", 1977 · Science · doi (opens in a new tab). A single, older study.
Mood, anxiety, sleep, fatigue, pain, migraine, dizziness, gut, sensory symptoms, focus, and how much it all got in the way. About two minutes.
Period start days go in once the ratings are done, not before.
Clinicians usually need at least two cycles of daily tracking. Three helps you see your own pattern clearly.
The three-cycle summary and appointment prompts turn "I feel crazy" into "here is the pattern I am living with."
Diagram of the cycle phases · lengths not to scale, and they vary between people and between cycles.
The free Cycle & Symptom Pattern Tracker covers three cycles.
Each one leads to a different conversation with a clinician. Daily tracking is how they're told apart, and a clinician makes the call.
Premenstrual dysphoric disorder: a diagnosis
At least five symptoms in the week before a period, including at least one core mood symptom. They ease within a few days of the period starting and are minimal in the week after. It's confirmed by daily ratings over at least two cycles. Confirmed this way, about 3 in 100 people who menstruate meet the criteria.
Reilly et al., 2024 · J Affect Disord · doi (opens in a new tab)
Premenstrual exacerbation: a worsening
An existing condition, such as depression, anxiety or ADHD, is there all month but gets worse before a period. If symptoms are still there in the week after your period, that points to PME or another condition rather than PMDD. PME is a research term, not yet an official diagnosis.
A condition that clusters by cycle phase
Migraine, asthma, epilepsy, IBS or POTS symptoms can cluster at certain points in the cycle. The mechanisms and the management differ by condition, so the pattern is something to bring to the clinician who treats it.
Pinkerton et al., 2010 · Am J Obstet Gynecol · doi (opens in a new tab)
What the research shows about conditions that change across the cycle. Every finding is labelled by how strong the evidence is.
1 in 5
In a Norwegian survey of 10,176 women aged 30 to 44, about 1 in 5 women with migraine (21%) met the criteria for menstrual migraine.
Vetvik et al., 2010 · J Headache Pain · doi (opens in a new tab)
~40%
About 40% of women with IBS say their cycle affects their symptoms. Around a third of women without gut problems also get gut symptoms during their period.
Mulak et al., 2014 · World J Gastroenterol · doi (opens in a new tab)
19–40%
Studies report that between about 1 in 5 and 2 in 5 women with asthma notice it getting worse around their period. This is called perimenstrual asthma.
Graziottin & Serafini, 2016 · Multidiscip Respir Med · doi (opens in a new tab)
In a questionnaire study of 65 women with POTS (a racing heart on standing) and 95 healthy women, both groups felt most light-headed during their period. Women with POTS were more light-headed in every phase.
Peggs et al., 2012 · Int J Gynaecol Obstet · doi (opens in a new tab)
In a pilot study of 30 women with ADHD taking stimulant medication, ADHD symptoms were worst during their period. If your medication seems to change across your cycle, that's something to raise with your prescriber.
Zaritsky et al., 2025 · J Atten Disord · doi (opens in a new tab)
In an online survey of 123 autistic and 114 non-autistic people, autistic respondents described sensory sensitivity and emotional regulation becoming harder around their period.
Steward et al., 2018 · J Autism Dev Disord · doi (opens in a new tab)
Get urgent care, rather than tracking, for a sudden severe "thunderclap" headache, new neurological symptoms such as weakness or loss of vision, fainting with an injury, chest pain or severe breathlessness.
I had a hysterectomy and both ovaries removed because of severe cyclical symptoms. I built this so you can see your pattern sooner.
I'm Rebecca. Oh Darling, It's Biology exists so you can see your pattern, understand the evidence behind it, and walk into appointments with something a clinician can work with.
Surgery was my path, decided with my clinicians. It isn't a recommendation for anyone else. UK guidance from the RCOG says removing the womb and both ovaries can be considered for severe PMS only when medical treatment has failed, after first trying a medicine that temporarily switches the ovaries off. If this is on your mind, talk to a clinician.
Green et al., 2016 · RCOG Green-top Guideline No. 48
A toolkit to help you prepare for cyclical-health appointments: what to bring, what to ask, and how to describe your pattern in clinical language.
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Free guides that pull the research on related conditions into one place. Every claim is labelled and linked to its source.
hEDS · POTS · MCAS · Migraine
Read the guideFibromyalgia · PMOS · IBS · Depression · Anxiety · OCD
Read the guideAutism · ADHD · AuDHD · Burnout
Read the guideDepression · Anxiety · OCD · Burnout
Read the guidePalpitations · Histamine · Brain fog · Sleep
Read the guideOne short email a week on how conditions change across the menstrual cycle, with every finding labelled by how strong the evidence is.
The free Cycle & Symptom Pattern Tracker is linked in every issue.
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