Painful Periods That Everyone Told You Were Normal

TL;DR: Bad period cramps are common, and common does not mean you have to live with them. There are 2 kinds. One kind comes from prostaglandins, which are chemicals that make the uterus squeeze hard during a period, with no disease underneath. The other kind is caused by a condition such as endometriosis, adenomyosis, or fibroids. Here is what to do, in order. 1) Take an anti-inflammatory such as ibuprofen or naproxen starting 1 to 2 days before your period is due, or at the very first twinge, and keep taking it on a set schedule for the first 2 to 3 days. Starting after the pain is already bad works much less well. 2) Use a heating pad on your lower belly and keep it on for hours, since in one trial that worked about as well as ibuprofen. 3) Write down 2 to 3 cycles: which days hurt, what the pain stopped you from doing, and what you took. 4) Get it looked at if the pain began years after your first period, if it gets worse every year, if it hurts on days you are not bleeding, if it hurts to have a bowel movement or to pee during your period, if sex hurts, or if the medicine that used to help has stopped helping. Those patterns point to a cause that someone needs to go find. And say this out loud at the visit: "I miss work because of this." It changes what happens next.

Most women with painful periods have heard some version of the same sentence since they were 13. Cramps are part of having a period, everyone gets them, take some ibuprofen and lie down. That advice fits often enough that it keeps getting repeated, and it misses often enough that people spend a decade calling out of Saturday doubles and riding the Market-Frankford home with a heating pad in their bag, in pain that had a name and a treatment the whole time.

Painful periods have a clinical name, dysmenorrhea, and they come in 2 forms that look alike from the outside and are handled very differently. Primary dysmenorrhea is cramping produced by the uterus itself, with no disease underneath it. Secondary dysmenorrhea is pain produced by something else: endometriosis, adenomyosis, fibroids, or a structural problem in how the uterus or cervix formed. Nearly everything that separates the 2 comes out of ordinary history questions, and most of the answers are things you already know about your own body.

Nobody has a tidy prevalence figure for this, because the surveys ask the question in different ways. A review of 15 studies published in Epidemiologic Reviews found reported prevalence anywhere from 16% to 91% of women of reproductive age, with severe pain in 2% to 29%. The range itself tells you something about how loosely this gets tracked. What is consistent across those studies is that a meaningful minority have pain that limits what they can do on those days, and that group has usually never been evaluated for it.

What causes period pain in the first place?

Period pain starts with prostaglandins. As the uterine lining breaks down at the end of a cycle, it releases prostaglandins, which are local signaling molecules that make the muscular wall of the uterus contract. Strong, sustained contractions squeeze the small arteries running through that wall, blood flow to the muscle drops, and the tissue starts producing the metabolic byproducts of working without enough oxygen. Those byproducts stimulate pain fibers. Women with more severe cramps tend to have higher prostaglandin levels in their menstrual fluid, and the same prostaglandins spilling into the bloodstream explain the rest of the package: nausea, loose stools, the low back ache, the headache, the flattened feeling on day 1.

That mechanism also explains the timing. Prostaglandin release depends on the hormonal sequence of an ovulatory cycle, and cycles in the first months after a first period are often anovulatory. So primary dysmenorrhea characteristically arrives once ovulatory cycles are established, usually within 6 to 12 months of menarche, rather than with the very first bleed. It typically begins a few hours before or right as bleeding starts, peaks over the first 24 to 48 hours, and eases after that.

The mechanism is what makes the treatment work. Anti-inflammatories block cyclooxygenase, the enzyme that builds prostaglandins in the first place, so they are treating the cause of the cramp rather than muffling the signal afterward. That is also why the hour you take the first dose matters as much as the dose itself.

What is the difference between primary and secondary dysmenorrhea?

Primary dysmenorrhea is period pain with no underlying disease driving it. It shows up in the first year or so of ovulatory cycles, holds a fairly steady pattern across the years, sits low in the pelvis and radiates into the low back and inner thighs, tracks tightly with the bleeding days, and often gets somewhat better with age and after a pregnancy. It responds to anti-inflammatories and to hormonal suppression of the cycle.

Secondary dysmenorrhea is period pain caused by an identifiable condition. The pain often starts days before bleeding and lingers after it stops. It tends to escalate year over year rather than hold steady. It frequently comes with other symptoms that primary dysmenorrhea does not produce: deep pain with sex, pain with bowel movements or urination during the period, heavy or irregular bleeding, trouble conceiving. American College of Obstetricians and Gynecologists guidance notes that secondary dysmenorrhea usually begins a few years after menarche and becomes more common after age 20.

Both ends of the timing spectrum deserve attention. Severe pain from the very first period, before ovulatory cycles are even established, raises the question of an obstructive anomaly, meaning menstrual blood that cannot drain the way it should because of how the uterus, cervix, or vagina formed. That is a structural problem, it is visible on imaging, and it is fixable. At the other end, pain that begins several years after menarche points toward disease acquired since then. In a case-control study of 563 women with surgically confirmed endometriosis and 563 age-matched controls across Switzerland, Germany, and Austria, onset of dysmenorrhea more than 3 years after menarche remained a significant predictor of an endometriosis diagnosis after adjusting for confounders (odds ratio 3.42, 95% CI 2.09 to 5.64).

Which features point toward an underlying cause?

These are the history features that move period pain out of the primary category and into a workup. Any single item is a reason to look, and 2 or 3 together make it fairly likely something is driving the pain:

• Onset years after periods began. Primary dysmenorrhea starts within roughly 6 to 12 months of menarche. Pain that arrived at 22, or at 31, arrived because something changed.
• Severe pain from the very first period. The opposite timing problem, and it raises the question of an obstructive anomaly rather than ordinary cramping.
• Pain outside the bleeding window. Mid-cycle pain, pain the week before, or pelvic pain that has started showing up on days that have nothing to do with the period.
• Pain that keeps getting worse. Primary dysmenorrhea usually holds a steady pattern or softens over the years. Progression in the other direction is a signal.
• Pain with bowel movements or urination during the period. Cyclic pain in those places suggests implants sitting on or near the bowel or bladder.
• Deep pain with sex. Pain felt deep in the pelvis with penetration, distinct from pain at the opening, points toward the pelvic side walls, the uterosacral ligaments, or the cul-de-sac.
• Heavy bleeding, flooding, or large clots. This pattern pushes toward adenomyosis and fibroids, and it also drives iron deficiency, which has its own long list of symptoms.
• An anti-inflammatory that used to work and stopped. ACOG advises investigating for secondary causes when dysmenorrhea has not improved within 3 to 6 months of appropriate treatment, and losing a response you used to have is the same message arriving later.
• Difficulty getting pregnant, or a mother or sister with endometriosis.

The 3 conditions behind most secondary dysmenorrhea look different from one another. Endometriosis is tissue resembling the uterine lining growing outside the uterus, and the World Health Organization puts it at roughly 10% of women of reproductive age; the classic pattern is pain that starts before bleeding, cyclic pain with bowel movements or urination, deep pain with sex, and infertility. Adenomyosis is that lining tissue growing down into the muscular wall of the uterus itself, and it presents mainly as heavy bleeding plus diffuse, dragging cramping, most often recognized in the 30s and 40s though it is increasingly found in younger patients. Fibroids are benign muscle tumors of the uterine wall that produce heavy bleeding, pressure, and urinary frequency alongside pain.

Why does a normal pelvic ultrasound not rule out endometriosis?

A normal pelvic ultrasound does not rule out endometriosis, and a lot of people have been sent home believing that it does. Ultrasound is a good test for the things that form a mass or distort anatomy: ovarian endometriomas, fibroids, the muscle-wall changes of adenomyosis, structural anomalies, and, in experienced hands with a dedicated protocol, deep infiltrating disease. It is a poor test for superficial peritoneal endometriosis, which is the most common form, because those implants are a thin scatter across the lining of the pelvis with no volume to reflect sound waves back. There is nothing there for the probe to find.

The 2022 European Society of Human Reproduction and Embryology endometriosis guideline states this directly: a negative ultrasound or MRI does not exclude endometriosis, particularly superficial disease. So "your ultrasound was normal" answers a narrower question than it sounds like it answers. It rules out an endometrioma, an obvious fibroid, and an obstruction, and it says nothing about whether implants are scattered across your peritoneum.

That same guideline made a second change that matters to anyone who has been told she cannot know without surgery. Laparoscopy is no longer positioned as the diagnostic gold standard. A working diagnosis can be made from symptoms and imaging, and medical treatment can be started on that basis, with surgery reserved for cases where imaging is negative and treatment has failed or is unsuitable. The old model, where the only route to being believed ran through an operating room, is part of why the gap between first symptom and diagnosis still averages somewhere between 8 and 12 years.

We are primary care, so our part of this is the evaluation, the treatment trial, the imaging order, and the referral when a surgical opinion belongs in the conversation. A definitive endometriosis diagnosis does not come out of a primary care evaluation. What we can do is take the pattern seriously, order the right first tests, start treatment that has evidence behind it, and get you to the right specialist with a history already assembled instead of starting from zero.

How should you take an anti-inflammatory so that it works?

Anti-inflammatories are the first-line treatment for primary dysmenorrhea, and most people are taking them in the way that works least well. The 2015 Cochrane review pooled 80 randomized trials in 5,820 women. Across the 35 trials comparing an NSAID against placebo, the odds of moderate or excellent pain relief were 4.37 times higher on the medication (95% CI 3.76 to 5.09). Put in absolute terms: if 18% of women get that level of relief on placebo, 45% to 53% get it on an anti-inflammatory. NSAIDs also beat acetaminophen (odds ratio 1.90, 95% CI 1.05 to 3.44). Side effects were more common on the medication (odds ratio 1.29, 95% CI 1.11 to 1.51), most of it indigestion and drowsiness, and the review rated most of the evidence low quality because of poor reporting in the older trials. It also found no basis for naming one NSAID the winner, so ibuprofen, naproxen, and mefenamic acid are all defensible starting points.

Timing is where the effect size lives, and it is a mechanism point rather than a preference. Once the cyclooxygenase cascade is running and prostaglandins have already been made and released, blocking the enzyme only slows further production; the molecules already circulating still have to be dealt with by your body. Blocking the enzyme before the cascade opens prevents most of that production from ever happening. In practical terms:

1. Start 1 to 2 days before your period is due if your cycle is predictable enough to call it. If it is not predictable, start at the very first twinge or the first spot of blood.
2. Dose on a schedule, not as needed, through the first 2 to 3 days of bleeding. That window is when prostaglandin release is highest, and a scheduled dose keeps the enzyme blocked between doses instead of letting production restart every few hours.
3. Take it with food, and keep to the labeled dose. Do not combine 2 different anti-inflammatories.
4. Talk it through first if you have a history of stomach ulcer or gastrointestinal bleeding, kidney disease, uncontrolled blood pressure, asthma that flares with these medications, or if you take an anticoagulant.

If you have given a properly timed, properly dosed anti-inflammatory a fair trial across 2 to 3 cycles and it has not touched the pain, that result is information rather than a dead end. It is one of the findings that moves the evaluation forward.

What else has evidence behind it?

Heat has been tested in randomized trials. In a double-dummy trial published in Obstetrics & Gynecology, continuous low-level topical heat applied for about 12 hours a day was as effective as ibuprofen 400 mg 3 times daily over 2 days, and the combination of heat plus ibuprofen brought relief faster than ibuprofen alone. A later meta-analysis pooling 3 randomized trials found heat favored over analgesic medication (standardized mean difference -0.72, 95% CI -0.97 to -0.48). The practical detail people miss is duration: this is continuous low-level heat worn for hours, rather than a hot water bottle for 10 minutes.

Hormonal suppression works, with more nuance than most patient pages carry. The 2023 Cochrane review of combined oral contraceptives for primary dysmenorrhea pooled 21 randomized trials in 3,723 women. Against placebo, the pill reduced pain by 0.7 to 1.3 points more on a 0 to 6 dysmenorrhea scale, and the review rated that high-certainty evidence. So the effect is established, and it is also modest in absolute size. Below that headline the picture thins out: evidence that the pill reduces work absence or the need for extra pain medicine was low certainty, and only 1 small trial has compared an oral contraceptive head to head against an anti-inflammatory, so nobody can tell you with any confidence which of the 2 will work better for you. Adverse effects are consistent, with headache reported in 19% to 35% on the pill versus 17% on placebo, and nausea in 11% to 22% versus 10%, plus irregular bleeding. One useful finding: continuous dosing, meaning skipping the hormone-free week so there is no withdrawal bleed, was probably more effective than the standard cyclic regimen. Beyond the pill, a levonorgestrel intrauterine device and progestin-only options are reasonable choices for many people, and the right pick depends on your goals around bleeding, contraception, and pregnancy timing.

Exercise probably helps, at low certainty. A 2019 Cochrane review of 12 trials in 854 women found that regular exercise, whether low intensity like yoga or higher intensity aerobic work, may produce a large reduction in period pain compared with no exercise. The certainty rating was low, so treat it as a reasonable addition rather than a substitute for the treatments above.

What should you track before the visit?

Track 2 to 3 full cycles before you come in. It costs a minute a day and it will do more for the visit than any test ordered on a first pass.

• Pain days against bleeding days. Call the first day of bleeding day 1, then mark which days hurt, including the days before day 1. Whether the pain leads the bleeding, tracks it, or trails it is one of the most informative pieces of the whole history.
• A 0 to 10 score at the worst point each day. Rough is fine. The trend across cycles matters more than the precision of any single number.
• What the pain stopped you doing. Work, class, the gym, plans you cancelled, hours spent lying down. Count the days.
• What you took, when, and whether it helped. The medication name, the dose, how many times a day, and how many hours after the pain started you took the first one. If you started before the pain, note that too, because that changes how the result should be read.
• Bleeding details. How many days, how often you change a pad or tampon on the heaviest day, whether you pass clots or flood through protection overnight, and any bleeding between periods.
• The other pains. Pain with sex, with bowel movements, with urination, and whether each one tracks the cycle.
• Family history. Endometriosis, fibroids, or heavy bleeding in your mother or sisters.

Now the sentence people leave out, usually because they have been trained to think it sounds dramatic: "I miss work because of this." Functional limitation is one of the axes the field uses to grade how severe dysmenorrhea is. The verbal multidimensional scoring system that Andersch and Milsom published in 1982, still in use, grades severity on 3 things: whether working ability is affected, whether systemic symptoms are present, and whether pain medicine is needed and whether it works. In their study of 19-year-old women, 72% reported dysmenorrhea and 15% had pain that limited daily activity and did not respond to analgesics. Saying that your pain costs you days is a clinical finding, and it belongs in the history.

How does Fishtown Medicine evaluate painful periods?

At Fishtown Medicine the first visit is mostly history, because the history carries most of the diagnostic weight here. We map the pain against the cycle, walk through the features above, ask about bleeding volume in terms you can estimate from your own week, and go through what you have already tried and how it was timed. A physical exam happens when it adds something to the picture.

From there the workup follows the history rather than covering everything at once. A complete blood count and ferritin when the bleeding is heavy, because iron deficiency runs alongside heavy periods constantly and explains fatigue, hair shedding, and exercise intolerance that often get blamed on something else. Thyroid testing when the cycle history warrants it. Testing for sexually transmitted infection when the picture raises the question, since pelvic inflammatory disease is a secondary cause that needs treating quickly. Pelvic ultrasound when a structural cause is on the table, ordered through your own insurance, with a clear conversation about what that scan can and cannot see.

Treatment starts while the evaluation runs, since ACOG supports beginning treatment when the history fits primary dysmenorrhea. That usually means an anti-inflammatory timed the way described above, continuous heat, and a conversation about hormonal options weighed against your own goals. We set a specific recheck at 3 months. If a properly timed and properly dosed plan has not helped by then, that finding drives the next step, which may be advanced imaging or a referral to gynecology with the history already assembled. Continuous access matters for a condition that only expresses itself a few days a month, because adjusting the plan should not require waiting 8 weeks for the next opening.

If your period pain has been dismissed for years and you are in Philadelphia, tell Dr. Ash what the pattern looks like and bring the cycles you tracked.

Guidance from the Clinic

"The first question I ask is when the pain started relative to her very first period, because that answer splits the picture in half. Cramps that began in the year after menarche and have held a steady pattern since are usually a treatment problem, and most of those patients have never been shown how to time an anti-inflammatory so it gets ahead of the prostaglandins instead of chasing them. Pain that started at 24, or has gotten worse every year, or shows up on days she is not bleeding, is telling me something is driving it, and that deserves a workup rather than another year of being told this is how periods go."

Related at Fishtown Medicine

• Endometriosis and what primary care can do about it - why the diagnosis takes years, and what to ask for while a referral is pending
• Adenomyosis, when periods are heavy and cramping is deep - the uterine-wall condition that gets mistaken for endometriosis and fibroids
• Iron, Heavy Periods, and Hair Loss - what heavy bleeding does to ferritin, and the symptoms that follow
• Heavy Periods and Anemia - breaking the loop where low iron makes bleeding heavier
• When You Need an Ultrasound, Body Part by Body Part - what pelvic imaging can and cannot answer
• Abdominal and Pelvic Imaging Guide - how ultrasound, CT, and MRI get chosen for pelvic pain
• Hormonal and metabolic testing for irregular cycles - the workup when cycles are long, skipped, or unpredictable
• When You Feel Dismissed by Your Doctor - what to do when your symptoms keep getting waved off
• Bladder Pain When Every Urine Culture Comes Back Negative - the pelvic pain condition that travels with endometriosis
• Perimenopause: The Window of Opportunity - how cycles and bleeding change in the 40s

Scientific References

1. Marjoribanks J, Ayeleke RO, Farquhar C, Proctor M. Nonsteroidal anti-inflammatory drugs for dysmenorrhoea. Cochrane Database of Systematic Reviews. 2015;(7):CD001751. https://pubmed.ncbi.nlm.nih.gov/26224322/
2. Schroll JB, Black AY, Farquhar C, Chen I. Combined oral contraceptive pill for primary dysmenorrhoea. Cochrane Database of Systematic Reviews. 2023;(7):CD002120. https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD002120.pub4/full
3. American College of Obstetricians and Gynecologists. Committee Opinion No. 760: Dysmenorrhea and Endometriosis in the Adolescent. Obstetrics & Gynecology. 2018;132(6):e249-e258. https://pubmed.ncbi.nlm.nih.gov/30461694/
4. Becker CM, Bokor A, Heikinheimo O, et al. ESHRE guideline: endometriosis. Human Reproduction Open. 2022;2022(2):hoac009. https://academic.oup.com/hropen/article/2022/2/hoac009/6537540
5. Ju H, Jones M, Mishra G. The prevalence and risk factors of dysmenorrhea. Epidemiologic Reviews. 2014;36(1):104-113. https://pubmed.ncbi.nlm.nih.gov/24284871/
6. Ferries-Rowe E, Corey E, Archer JS. Primary Dysmenorrhea: Diagnosis and Therapy. Obstetrics & Gynecology. 2020;136(5):1047-1058. https://pubmed.ncbi.nlm.nih.gov/33030880/
7. Akin MD, Weingand KW, Hengehold DA, Goodale MB, Hinkle RT, Smith RP. Continuous low-level topical heat in the treatment of dysmenorrhea. Obstetrics & Gynecology. 2001;97(3):343-349. https://pubmed.ncbi.nlm.nih.gov/11239634/
8. 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. Scientific Reports. 2018;8(1):16252. https://www.nature.com/articles/s41598-018-34303-z
9. El-Hadad S, Lässer D, Sachs MK, et al. Dysmenorrhea in adolescents requires careful investigation of endometriosis: an analysis of early menstrual experiences in a large case-control study. Frontiers in Reproductive Health. 2023;5:1121515. https://pubmed.ncbi.nlm.nih.gov/37693279/
10. Andersch B, Milsom I. An epidemiologic study of young women with dysmenorrhea. American Journal of Obstetrics and Gynecology. 1982;144(6):655-660. https://pubmed.ncbi.nlm.nih.gov/7137249/
11. Armour M, Ee CC, Naidoo D, et al. Exercise for dysmenorrhoea. Cochrane Database of Systematic Reviews. 2019;(9):CD004142. https://pubmed.ncbi.nlm.nih.gov/31538328/
12. World Health Organization. Endometriosis fact sheet. https://www.who.int/news-room/fact-sheets/detail/endometriosis