Do Women Pass Kidney Stones? Symptoms & Treatment

Women absolutely do pass kidney stones, and they are doing so at rising rates. While men have historically been roughly twice as likely to develop stones, that gap has been narrowing for decades. One nationally representative study found the male-to-female ratio of treated stone disease dropped from 1.7-to-1 down to 1.3-to-1 over just five years.¹ The experience of passing a stone, from the searing flank pain to the treatment decisions that follow, does differ in several ways for women compared to men.

Why Kidney Stones Are Becoming More Common in Women

The old rule of thumb that kidney stones are a “man’s problem” is increasingly outdated. Across multiple large datasets, the rate of stone disease in women has been climbing faster than in men. Between 1998 and 2004, procedures for urinary stones in women jumped by about 52%, compared with a 22% increase in men.² A broader analysis confirmed the trend: while men’s overall stone risk has actually declined somewhat over time, women’s risk has been heading in the opposite direction.³

What is driving this shift is still debated. Rising rates of obesity in women are likely part of the picture, since higher body mass index is a strong and well-established risk factor for stones. A large study following postmenopausal women found that higher BMI categories were consistently associated with a greater chance of forming a first stone.⁴ Dietary changes, including increased sodium and animal protein consumption, and possibly the widespread use of calcium supplements may also be contributing. Whatever the exact mix of causes, the practical takeaway is that kidney stones are not rare in women, and doctors who dismiss flank pain in a woman as “probably something else” are working from outdated assumptions.

How Symptoms Show Up Differently in Women

The hallmark of a kidney stone on the move is renal colic: sudden, intense pain in the back or side, often radiating down toward the groin. This core experience is the same regardless of sex. But women face a diagnostic wrinkle that men do not. The same region of the body where stone pain lands also overlaps with pain from ovarian cysts, ectopic pregnancy, endometriosis, and pelvic inflammatory disease. A large retrospective study of over 3,300 women presenting with flank pain found that a confirmed urological diagnosis was identified in only about 55% of cases, with urinary tract infections and kidney stones being the most common findings.⁵ That means roughly half the time, flank pain in women had a non-urological explanation, which helps illustrate why the diagnostic process can take longer.

Women with stones also tend to report nausea and vomiting more frequently, and urinary symptoms like burning or urgency can be mistaken for a simple bladder infection, especially if a urine test shows some blood or bacteria. This overlap means women sometimes go through one or more rounds of antibiotics for a presumed UTI before anyone orders imaging to look for a stone. If you have recurring “UTIs” that do not fully resolve with antibiotics, or if flank pain keeps coming back, it is worth asking whether a stone could be the real culprit.

The Estrogen Connection and What Happens After Menopause

One of the main reasons women historically had fewer stones than men appears to be estrogen. Before menopause, estrogen seems to influence how the kidneys handle calcium. A study comparing postmenopausal women on estrogen therapy with those not receiving it found that the treated group had lower urinary calcium levels and lower calcium oxalate saturation, both of which translate to a reduced environment for stone formation.⁶ Separately, researchers comparing urine chemistry in pre- and postmenopausal women confirmed that after menopause, certain protective factors like citrate (a natural stone inhibitor) tended to decline.⁷

This is where it gets counterintuitive. You might expect that hormone replacement therapy would restore that protection. But the Women’s Health Initiative, a large randomized trial, found the opposite: postmenopausal women taking estrogen therapy actually had a higher rate of kidney stones, rising from about 34 to 39 cases per 10,000 person-years.⁸ That increase held whether or not progestin was added. The researchers noted that the sex difference in stone rates narrows considerably by the sixth decade of life, right around the time menopause typically occurs. So while natural estrogen during reproductive years appears protective, supplementing it afterward does not simply re-create that benefit and may even work against you. If you are on hormone therapy and have a history of stones, this is worth discussing with your doctor.

Kidney Stones During Pregnancy

Pregnancy creates a kind of perfect storm for stone formation. The growing uterus compresses the ureters against the pelvic bones, and elevated progesterone slows the rhythmic muscle contractions that normally push urine along. Together these changes cause mild swelling of the kidneys (hydronephrosis) in up to 90% of pregnancies. Urine sits in the system longer, giving minerals more time to crystallize. On top of that, pregnancy drives up urinary calcium through multiple routes: the body absorbs more calcium from food, pulls more from bone stores, and the kidneys filter more of it due to a higher blood-flow rate. Routine calcium and vitamin D supplements add to the load. Urine pH also rises during pregnancy, which favors the formation of calcium phosphate stones specifically.⁹

Despite all these risk factors stacking up, symptomatic stones during pregnancy are still uncommon, affecting roughly 1 in 200 to 1 in 1,500 pregnancies depending on the study. But when they do occur, management is tricky. The usual first-line imaging (a CT scan) involves radiation that you want to avoid during pregnancy, so ultrasound becomes the go-to, even though it is less sensitive. Treatment is also more conservative. A small study looking at tamsulosin (a medication sometimes used to help stones pass) in pregnant women found a spontaneous passage rate of about 58% in the treatment group compared with 43% in the untreated group, but the difference was not statistically significant.¹⁰ In practice, most pregnant women with stones are managed with fluids, pain control, and close monitoring, with surgical intervention reserved for cases involving infection or obstruction that threatens the kidney.

How Diagnosis Works and Why Imaging Choices Matter

Non-contrast CT is considered the gold standard for identifying kidney stones, with sensitivity typically in the range of 86% to 98% and specificity approaching 100%.¹¹ Ultrasound, while free of radiation, has more variable sensitivity, generally in the 67% to 85% range, and depends heavily on the operator’s skill.¹² However, a randomized trial comparing the two in an emergency setting found that their overall diagnostic accuracy was roughly equivalent in practice, meaning ultrasound may be a reasonable first step even outside pregnancy.¹³

For women of childbearing age, the radiation question matters more than for older patients or men. A combined approach (ultrasound first, low-dose CT only if needed) is increasingly popular because it balances accuracy against radiation exposure. Plain X-rays still have a role in follow-up, since they can track whether a known stone is shrinking or moving, but they miss non-calcium stones entirely and have moderate sensitivity around 78%.

Women Form Different Types of Stones

Not all kidney stones are the same chemical substance, and the mix differs between men and women. A large analysis of stone composition found that women submitted the majority of hydroxyapatite (a type of calcium phosphate) and struvite stones, accounting for about 65% of each type. Men, by contrast, submitted the majority of calcium oxalate stones (64%) and uric acid stones (72%).¹⁴

These differences are not academic curiosities. They affect treatment and prevention. Struvite stones, sometimes called infection stones, form in the setting of certain urinary tract infections caused by bacteria that split urea. Women get UTIs far more frequently than men, which partly explains their higher share of struvite stones. These stones can grow large and branching (so-called “staghorn” stones) and almost always require procedural removal rather than watchful waiting. The higher proportion of calcium phosphate stones in women also lines up with the alkaline urine that estrogen and pregnancy promote. If you have had a stone, saving it for analysis or asking your doctor about the composition can meaningfully change the prevention strategy.

Treatment Options

Most small stones, generally those under about 5 or 6 millimeters, pass on their own with time, fluids, and pain management. The treatment approach does not differ dramatically between men and women for a simple uncomplicated stone. Nonsteroidal anti-inflammatory drugs are typically first-line for pain, sometimes supplemented with a short course of opioids for severe episodes. Alpha-blockers like tamsulosin are sometimes prescribed to relax the smooth muscle of the ureter and help the stone move along, though the benefit is most convincing for stones between 5 and 10 millimeters.

When a stone is too large to pass, too painful, or causing an obstruction or infection, procedural intervention becomes necessary. The two main options are ureteroscopy (where a thin scope is threaded up through the bladder to break up or extract the stone) and extracorporeal shockwave lithotripsy (which uses focused sound waves from outside the body to fragment the stone into passable pieces). A recent large study comparing the two in younger patients found essentially equivalent stone clearance rates, around 71% for ureteroscopy and 68% for lithotripsy, but ureteroscopy came with more pain and more missed days of school or work in the first week.¹⁵ In adults, the choice between procedures depends on stone size, location, composition, and patient anatomy. Women’s shorter urethra can make ureteroscopy slightly easier to perform, but the decision is individualized.

The Quality-of-Life Gap

One area where the data is striking and underappreciated is quality of life. Women who form kidney stones consistently report lower quality-of-life scores than men with the same condition. A study using a validated stone-specific questionnaire found that women scored significantly lower across every domain tested: social impact, emotional impact, disease impact, and vitality. The overall score averaged about 72 for women compared with 81 for men, and being female was identified as an independent predictor of diminished quality of life even after adjusting for factors like number of surgeries and symptom status.¹⁶ A separate study confirmed the pattern, finding that female sex, age over 50, and obesity were all linked to worse quality-of-life scores among stone patients.¹⁷

Why the gap exists is not entirely clear. It may reflect the diagnostic delays women experience, the overlap with gynecological symptoms that can amplify anxiety, or broader patterns in how chronic pain conditions affect women differently. Whatever the cause, the finding suggests that women with recurrent stones may benefit from more proactive follow-up and psychological support, not just stone-focused treatment.

Long-Term Kidney Risks

Kidney stones are not just painful episodes to endure and forget. Having even one stone episode is associated with a higher risk of chronic kidney disease down the road, and that excess risk appears to be greater in women than in men. A large cohort study found that while both sexes faced elevated risks of kidney function loss after stone episodes, the association was stronger in women and in people under 50.¹⁸ This does not mean every woman who passes a stone will develop kidney problems, but it does mean that follow-up matters. Getting a metabolic workup (a 24-hour urine collection and blood tests) after a first stone can identify treatable risk factors that reduce the chance of recurrence and protect kidney function over time.

Prevention Strategies That Actually Help

The single most reliable preventive measure is drinking enough fluid to produce at least two liters of urine per day. That sounds straightforward, but adherence is harder than it seems. Night-shift and rotating-shift workers, for instance, are significantly less likely to maintain adequate hydration, as are people with limited access to water or bathrooms at work.¹⁹ Women in healthcare, teaching, retail, and manufacturing often face exactly these constraints.

On the diet side, one of the most persistent myths is that you should avoid calcium if you form calcium stones. The evidence says the opposite. Research on older women found that increased dietary calcium intake reduced the likelihood of stones by roughly 45% to 54%, and even calcium supplementation was associated with a lower chance of stone history.²⁰ Current guidance is clear: dietary calcium restriction is no longer recommended, because it can weaken bones without reducing stone risk.²¹ The key distinction is between calcium from food (protective) and calcium from supplements taken apart from meals (potentially problematic, since it may raise urinary calcium without the binding effect of dietary oxalate). Taking supplements with meals helps mitigate this.

Beyond calcium, reducing sodium intake matters because high sodium drives calcium excretion into the urine. Adequate citrate from fruits (especially citrus), limiting animal protein, and maintaining a healthy weight round out the main dietary strategies. For women with recurrent stones, targeted medication like thiazide diuretics (which lower urinary calcium) or potassium citrate (which raises urinary citrate and makes urine less acidic) can cut recurrence rates substantially, though these require a doctor’s prescription and monitoring.

When Workplace and Lifestyle Barriers Get in the Way

Prevention advice that boils down to “drink more water” glosses over how difficult that is for many women in practice. The hydration study mentioned above quantified what many people already know from experience: limited bathroom access at work cut hydration adherence nearly in half, and restricted water availability had a similar effect.¹⁹ If you work in a setting where taking a water bottle or stepping away to use the restroom is frowned upon, the standard prevention advice is not going to help unless you also address the structural barriers. Some women find it useful to front-load hydration during off-hours, or to keep track of urine color as a practical gauge rather than aiming for a specific volume.

Obesity deserves its own mention here as well. For postmenopausal women in particular, higher BMI is one of the strongest modifiable risk factors for a first stone.⁴ The relationship between weight and stones runs through several channels, including insulin resistance (which lowers urine pH and promotes uric acid stones) and increased oxalate and calcium excretion. Weight loss, even modest, can shift the urinary chemistry in a favorable direction.