Painful Periods

Why Do Menstrual Cramps Happen? A Deep Dive into Dysmenorrhea

By Dr. Anita Mitra (The Gynae Geek)

Painful periods, referred to in medical speak as ‘dysmenorrhea’ is thought to affect up to about 90% of people having periods, and may be classified as severe in up to 30% (1). If it’s such a common symptom, why do we understand so little about it and why do we feel such a need to underplay our symptoms?

Historically, period pain has often been dismissed as psychosomatic, ‘all in the mind’ and just something that is just part of ‘being a woman’. Let me start by saying one thing… if you say that you have pain, I BELIEVE YOU. When I ask my patients to tell me more about their period pain, a surprisingly large proportion will start their explanation with “I’ve got a really high pain threshold but…”, or words to that effect. Admittedly I’ve spent most of my career working in Obstetrics & Gynaecology, but in my experience of working in other medical specialties, I don’t recall hearing this phrase used so consistently to describe pain in any other part of the body. This is a clear demonstration of how we’ve been conditioned to just put up with period pain and I’m on a mission to stop that.

 
What is actually causing painful periods?

Throughout the menstrual cycle, the endometrium, which is the lining of the uterus (also known as the womb), builds up in the hope of housing a pregnancy. Progesterone, the hormone that is produced after ovulation is responsible for maintaining the lining and helping the network of blood vessels to develop which would provide the necessary blood supply and nutrients to a fertilised egg. If a fertilised egg doesn’t try to implant, there is a drop in oestrogen and progesterone which means the body isn’t able to maintain the endometrium, and the upper two-thirds will shed away in the next week or so (see article on the menstrual cycle here). It is this endometrial lining, along with some blood and actually a fair amount of water that is your period. The drop in progesterone also prompts the body to make prostaglandins; a chemical messenger that causes the uterus to contract in order to help shed and expel the lining. This contraction is also responsible for period pains.

Studies of women experiencing severe period pain, have been shown to produce higher levels of prostaglandins, compared to those who don’t, and higher levels correlated directly with higher levels of pain (2). This may also result in more intense contraction of the muscle of the uterus, causing a greater reduction in blood supply and, ultimately oxygen supply, which also contributes to the pain. This is often described as being like a heart attack in your uterus, which from a biological perspective is incredibly similar. So, whilst we’re often led to believe we’re just making it up, there is indeed objective evidence of molecular and chemical changes in the bodies of women who are affected by painful periods, compared to those who are not. 

Period pains are most commonly felt in your lower abdomen and back, however some people may experience pain that travels into the buttocks or thighs which happens because of a cross-communication between the nerves in your pelvis.

You can also experience period pains as a result of an underlying gynaecological condition, such as endometriosis, adenomyosis, or fibroids, which is referred to as ‘secondary dysmenorrhoea’. In this situation, pain often lasts longer than your period does and can be associated with other symptoms such as heavy or prolonged bleeding, so these are the types of questions that your doctor will ask you when trying to get to the bottom of your symptoms. When there is no known underlying cause, the term ‘primary dysmenorrhoea’ is used. 

So, how much is too much?

Now that you understand that the uterus has a bit of work to do to get the blood and uterine lining out, you can appreciate that it’s fairly normal get a little bit of discomfort. But one of the most frequently asked questions that I get is “How much is too much?” In this situation, you are your own barometer because we all have a different levels of what we are prepared to tolerate.

Things that might cause me to raise an eyebrow are if you’re clock-watching to work out when you can take more painkillers and if can’t do the things that you need, or want, to do in everyday life. And if you ever tell me that you’re lying on the floor curled up in a ball…that is NEVER normal. Overall, having period pain that affects your quality of life is something that needs to be investigated and managed.

What can you do about it?

Whilst lying in the fetal position might help because it’s relaxing your abdominal muscles, it’s never top of my list when it comes to management strategies. So, here’s what you can actually do to help…

• Exercise – Exercising three time per week, for about 45–60 minutes at a time, can have a really positive effect on period pain (3), but remember you need to do this for the whole month. It is safe to exercise during your period and it can be helpful to reduce pain, bloating and just give you a general wellbeing boost, however if you don’t feel like it, that’s absolutely fine too. There isn’t really one type of exercise that’s better than another, so as I always tell my patients, do whatever you enjoy.
  
  
• Over-the-counter painkillers - I'm about things like paracetamol, ibuprofen & aspirin that you can buy without a prescription. Paracetamol & ibuprofen or aspirin can be used together at their respective full-doses because they have different mechanisms of action and work to reduce the release and effect of inflammatory compounds such as prostaglandins that are responsible for the pain (4). Ibuprofen and aspirin should not be taken together. Whilst over-the-counter painkillers can be very effective for mild to moderate pain, they won’t mask anything sinister, which is understandably a concern that many patients voice. 
  
  
• Heat – using heat therapy in the form of a hot water bottle is an age-old remedy for pain symptoms that can actually help by aiding relaxation of tense abdominal muscles that can spasm in response to the pain, and be improving blood flow to help reduce swelling & congestion that can press on nerves adding to the pain (5). I see a lot of patients with chronic pain who have skin discolouration called ‘erthyema ab igne’, also known as ‘toasted skin’ or ‘hot water bottle rash’ which occurs due to repeated heat exposure, so do try to limit the amount of time that you’re using heat and speak to your doctor about other measure you can take to address your symptoms.
  
  
• Transcutaneous electrical nerve stimulation (TENS) machines – these are attached to your body at sites of pain via small sticky electrodes which then deliver a mini electric current which can block pain signals and may even reduce the oxygen-supply issue to the uterus that I mentioned above (6).
  
  
• Diet – there a lot to be said about diet and it deserves its own article, but let me summarise things here; there isn’t one food or food group that has been shown to cause or treat period pain in isolation. The main culprits that I’m most frequently asked about are dairy, gluten, red meat and sugar. Whilst there’s no population-based evidence that these cause or worsen period pain, you have to remember that population-based studies provide an average – so in a population, you will find that most people don’t really notice any impact, and some people find they worsen their pain, and some might even find it makes it better. So, do remember that you’re an individual and what works for you, might not work for another. If you think a specific food is worsening your symptoms I would recommend reducing or cutting it out and keeping a symptom diary for at least 3 months to see what the impact is, but you may also want to seek advice from a qualified nutritionist or dietician to make sure you’re not missing out on crucial nutrients. With regards to what you can add into your diet, you want to focus on brightly coloured fruits and vegetables that contain plenty of important micronutrients, omega-3 fatty acids and vitamin D to help reduce inflammation, as well as sources of iron and fibre. To capture all of this I would recommend a Mediterranean-style diet, with plenty of vegetables, legumes (such as lentils, peas, beans, chickpeas) fruits, nuts, wholegrain cereals, olive oil as the main source of fat, moderate amounts of dairy, including yoghurt and cheese, with fish and lean meat and a relatively small amount of red meat or processed foods.
  
  
• Nutritional supplements - The Kahun Gynaecological Papyrus, the oldest known Egyptian medical document, dating back to 1825BC contains the oldest known treatment for period pains: “a measure of carob fruit, a measure of pellets, 1 hin of cow milk. Boil, cool, mix together, drink on 4 mornings”. No one really knows what the pellets are, but it’s unlikely to be anything palatable! Thankfully there are better supplements out there which is where DITTO Cycle Supplement comes in.. it contains Vitamin D, Omega-3 and Zinc, all shown in randomised, placebo-controlled trials to significantly reduce the severity and duration of period pain (7-9).

See your doctor! On top of all of these thing that you can do at home, there is a lot that we can offer in terms of prescription medications, investigations to look for underlying causes and offering more tailored treatments depending on your individual situation.

My most recent book 'Dealing with Problem Periods' covers the conditions that are most frequently responsible for painful periods, and more details of the rationale for various treatments, their benefits and side effects.

1. Ju H, Jones M, Mishra G. The prevalence and risk factors of dysmenorrhea.Epidemiol Rev. 2014;36:104-113.
2. Lundström V, Gréen K. Endogenous levels of prostaglandin F2alpha and its main metabolites in plasma and endometrium of normal and dysmenorrheic women.Am J Obstet Gynecol. 1978;130(6):640-646.
3. Zheng, Q., Huang, G., Cao, W. et al. Comparative effectiveness of exercise interventions for primary dysmenorrhea: a systematic review and network meta-analysis. 2024. BMC Women's Health. 24,610.
4. Dawood MY, Khan-Dawood FS. Clinical efficacy and differential inhibition of menstrual fluid prostaglandin F2alpha in a randomized, double-blind, crossover treatment with placebo, acetaminophen, and ibuprofen in primary dysmenorrhea.Am J Obstet Gynecol. 2007;196(1):35.e1-35.e355.
5. Jo J, Lee SH. Heat therapy for primary dysmenorrhea: A systematic review and meta-analysis of its effects on pain relief and quality of life. Sci Rep. 2018;8(1):16252
6. Han S, Park KS, Lee H, et al. Transcutaneous electrical nerve stimulation (TENS) for pain control in women with primary dysmenorrhoea. Cochrane Database Syst Rev. 2024;7(7):CD013331.
7. Chen YC, Chiang YF, Lin YJ, et al. Effect of Vitamin D Supplementation on Primary Dysmenorrhea: A Systematic Review and Meta-Analysis of Randomized Clinical Trials. Nutrients. 2023;15(13):2830.
8. Hsu TJ, Hsieh RH, Huang CH, et al. Efficacy of Zinc Supplementation in the Management of Primary Dysmenorrhea: A Systematic Review and Meta-Analysis. Nutrients. 2024;16(23):411
9. Snipe RMJ, Brelis B, Kappas C, et al. Omega-3 long chain polyunsaturated fatty acids as a potential treatment for reducing dysmenorrhoea pain: Systematic literature review and meta-analysis. Nutr Diet. 2024;81(1):94-106.

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