Period Red Flags: What Your Body Is Trying to Tell You

Periods are rarely a walk in the park, but there's a significant difference between a manageable monthly inconvenience and symptoms that are genuinely harming your quality of life. Too often, people suffering from debilitating cramps, mood crashes, heavy bleeding, or severe bloating are told it's "just part of being a woman" - and that normalisation can be super harmful. These symptoms are usually a sign from your body that something isn’t right, and ignoring these warning signs (or those signs being ignored by a doctor!) can delay diagnoses by years.

Here's what you need to know about the period symptoms that deserve a second look, and when it's time to speak to your doctor.

Red Flag #1: Debilitating Period Pain

Some cramping is entirely normal. But pain that stops you from going to work, attending school, socialising, or functioning in daily life is not something to simply push through.

Warning signs include:

• Pain so severe it requires you to stay in bed

• Cramping that doesn't respond to over-the-counter painkillers like ibuprofen or paracetamol

• Pain that begins several days before your period and lingers long after it ends

• Deep, stabbing, or radiating pain in the pelvis, lower back, or legs

Conditions this could signal:

Endometriosis is one of the most common culprits. It occurs when tissue similar to the womb lining grows outside the uterus - on the ovaries, fallopian tubes, or elsewhere in the body. It affects approximately 1.5 million women in the UK, a similar number to those living with diabetes (Endometriosis UK). Globally, it's estimated that 6–13% of women of reproductive age are affected (NCBI, 2024). Heartbreakingly, the average time from first GP visit to diagnosis in the UK is currently over nine years (Endometriosis UK Diagnosis Report 2026).

Adenomyosis - occurs when the womb lining grows into the muscular wall of the uterus itself, causing the womb to enlarge and menstruation to become intensely painful. It often co-exists with endometriosis and is frequently underdiagnosed.

Fibroids - non-cancerous growths in or around the uterus - can also cause significant cramping, particularly when they distort the uterine cavity.

When to see a doctor: If your pain is regularly interfering with your daily life, track your symptoms across two to three cycles and book an appointment with your GP. Don't downplay it. Bring specific details: where the pain is, how long it lasts, and what score you'd give it out of ten.

Red Flag #2: Extreme PMS or PMDD

Mild PMS -  a little bloating, low mood, or fatigue in the days before your period -  is experienced by the vast majority of people who menstruate. But when premenstrual symptoms start to seriously disrupt your life, they become a red flag.

Between 2 and 4 in 100 women experience PMS severe enough to prevent normal daily activities, according to evidence submitted to Parliament by the Royal College of Obstetricians and Gynaecologists. A small but significant percentage go further and experience Premenstrual Dysphoric Disorder (PMDD) — a severe mood disorder linked to hormonal sensitivity. Research estimates PMDD affects around 3–5% of women of childbearing age (European Psychiatry, 2022).

Symptoms of PMDD can include:

• Severe depression, anxiety, or rage that feels out of proportion

• Suicidal thoughts

• Extreme fatigue and inability to concentrate

• Feeling completely out of control in the week or two before your period — and then relatively fine once it begins

PMDD is not just "bad PMS." It is a recognised psychiatric and gynaecological condition that responds to treatment, including SSRIs, hormonal therapies, and lifestyle interventions.

When to see a doctor: If your mood, energy, or mental health is consistently and significantly worsening in the lead-up to your period - and then lifting once it arrives - speak to your GP. Keep a symptom diary for at least two cycles to show the pattern clearly.

Red Flag #3: Extreme Bloating

Some bloating around your period is hormonal and normal. But extreme, painful, or persistent bloating that makes you feel like you've gone up a dress size overnight, or that causes significant physical discomfort, is worth investigating.

Serious bloating can be associated with:

• Endometriosis, particularly when it affects the bowel

• Adenomyosis, as the enlarged uterus pushes against surrounding organs

• Fibroids, which can cause visible abdominal swelling

• Irritable Bowel Syndrome (IBS), which often worsens around menstruation due to hormonal effects on the gut

Endometriosis in particular can cause what some patients describe as "endo belly" — a rapid and dramatic swelling of the abdomen that can be both painful and distressing.

When to see a doctor: If bloating is severe, painful, or accompanied by changes in bowel habits (constipation, diarrhoea, or pain when going to the toilet) around your period, raise it with your GP. These are important clues that point to conditions that deserve proper investigation.

Red Flag #4: Heavy Periods

Medically, a heavy period (known as menorrhagia) is defined as losing 80ml or more of blood per cycle. In practical terms, a common rule of thumb used by clinicians is needing to change a pad or tampon more frequently than every three hours, passing large clots (bigger than a 50p piece), or bleeding through to your clothes or bedding.

Heavy periods are more common than many people realise, but they are not something you simply have to live with. They can cause iron-deficiency anaemia, leading to fatigue, breathlessness, and brain fog that persist long after your period ends.

Causes of heavy bleeding include:

• Fibroids: Research shows that around 63.8% of women with uterine fibroids report heavy menstrual bleeding (NCBI, 2023), making it one of the most common presenting symptoms

• Adenomyosis: The womb lining grows into the muscle, increasing blood loss significantly

• Endometriosis: Particularly when it affects the ovaries or causes adhesions

• Hormonal imbalances, including thyroid disorders or polycystic ovary syndrome (PCOS)

• Polyps inside the uterus

When to see a doctor: If you are regularly changing protection every three hours or less, passing large clots, or feeling exhausted and dizzy during your period, book an appointment. Ask for a blood test to check for anaemia as a starting point, and request an ultrasound to look for fibroids, polyps, or signs of adenomyosis.

Why Period Underwear Could Be a Game-Changer

If you're dealing with heavy or unpredictable bleeding- whether diagnosed with a health condition or not - period underwear is worth knowing about. Unlike disposable pads or tampons, period knickers are reusable, comfortable, and designed to absorb menstrual blood directly, offering leak-free protection without the need for additional products. They also don’t come with the host of toxic chemicals often found in traditional period care products. These chemicals can play havoc with your hormones, which can make conditions like endo worse, and whilst there is very little research into the impact of period care on menstrual health conditions, some early anecdotal evidence indicates that swapping to reusable products can potentially reduce pain! 

For people with heavy, painful periods, they offer several advantages:

• Reliable overnight protection without the anxiety of leaking

• Freedom from frequent changes -  quality period underwear can hold the equivalent of multiple tampons' worth of blood

• No dryness or irritation caused by disposable products - a genuine benefit for those whose skin is already sensitive during menstruation

• Eco-friendly and cost-effective in the long run

• Peace of mind - particularly when bloating or cramping makes tampons uncomfortable or inserting them painful

NIXI Body is a leading UK brand in this space, offering period underwear designed with both comfort and high absorbency in mind. Their range caters to light, moderate, and heavy flow days, making them a practical choice whether you're managing a heavy bleed or simply want a more comfortable, sustainable period experience. For anyone navigating a new diagnosis — or waiting for one — they can offer a small but meaningful improvement to everyday life during your cycle.

The Most Important Thing: You Deserve to Be Heard

If you recognise yourself in any of the red flags above, the most important thing to know is this: you are not being dramatic, and you are not alone.

Women's health conditions - particularly those involving menstrual symptoms - are historically underfunded and under-researched. The nine-year average diagnosis time for endometriosis in the UK is a stark illustration of how long people are left suffering without answers.

Track your symptoms. Use a period app, a notebook, or a simple spreadsheet. Note the pain level, flow, mood, bloating, and how much it impacts your ability to function. That record is one of the most powerful tools you can bring to a GP appointment — and it can be the difference between being dismissed and being referred.

Your period is not supposed to derail your life. If it is, it's time to ask why.

Always consult a qualified medical professional for personal medical advice. This article is for informational purposes only.