Kidney Stones: Are They Different for Women?

Both men and women can get kidney stones. A urologist with USC Verdugo Hills Hospital, part of Keck Medicine of USC, offers women special advice for managing them.

Passing a kidney stone is right up there with “eating a frog” or “sticking needles in my eyes” on the list of things we don’t want to do.

But kidney stones aren’t often on the list of things women think about when experiencing issues “down there.” Jamal Nabhani, MD, a urologist with USC Urology, part of Keck Medicine of USC, who also treats patients at USC Verdugo Hills Hospital, thinks they should be.

What is a kidney stone?

A kidney stone is crystallization of minerals and salts that are usually dissolved in urine.

“When they come out of solution, they can create a small crystal, like a grain of sugar,” Dr. Nabhani explains. “Slowly over time, these grow to the size of a small pebble and, in extreme cases, can grow large enough to fill the entire area where your urine collects in your kidney.”

That’s when a kidney stone — also called a nephrolith, from “nephro-,” meaning “kidney,” and “-lith,” meaning “stone” — can start causing problems.

What are the complications of kidney stones?

Although small stones often pass through the urinary tract without incident, larger ones can get stuck, blocking the ureter that connects the kidney to the bladder and causing considerable pain, Dr. Nabhani says.

“The most dangerous presentation,” he adds, “is a kidney stone superimposed with an infection, which can land people in the ICU and become life-threatening if they don’t get prompt attention.”

Do women get kidney stones?

These complications can strike anyone who develops a kidney stone — and according to Dr. Nabhani, 12% of us at some point in our lives will.

And though men have historically suffered from a higher incidence of kidney stones than women, women seem to be catching up.

One reason is poor diet. “Some of the biggest risk factors for developing kidney stones are increased salt intake, high protein intake and not eating many fresh fruits and vegetables,” Dr. Nabhani says. “So, as we’ve seen the Western diet deteriorate, the prevalence of kidney stones has increased for both men and women.”

Infection connection

Another reason women are developing more kidney stones involves urinary tract infections (UTIs).

Kidney stones and UTIs have an interesting relationship: The former, by blocking urinary flow, can set the stage for bacterial infection; meanwhile, UTIs can exacerbate the formation of the kidney stones most likely to affect women.

As Dr. Nabhani explains, “Kidney stones come in various compositions, and women tend to get more of what we call struvite stones, which are caused by recurring urinary tract infections.”

As cases of struvite stones grow more common, Dr. Nabhani wants women — especially those prone to recurrent UTIs — to know about the risk.

More than just a “women’s issue”

He also wants women to know that many symptoms they might associate with routine gynecological conditions may, in fact, signal kidney stones.

“Patients with kidney stones will often present with flank or back pain, pain in the lower abdomen or burning in the pelvis,” he says, “and those can all be confounded by menstrual pain and PCOS,” or polycystic ovary syndrome, a hormonal disorder that strikes women of reproductive age.

Doctors may also mistake kidney stone symptoms for those of a UTI — a case of mistaken identity that’s complicated further by the fact that women can have both a UTI and a kidney stone at the same time.

“These are things that women, as advocates for themselves, need to be aware of,” Dr. Nabhani says, “particularly if they’re experiencing frequent UTIs or have unexplained abdominal or back pain. Patients have to be persistent with their doctors, and doctors have to listen.”

Kidney stones and pregnancy

Women should also understand the considerations surrounding kidney stones and pregnancy.

“Your physiology changes significantly during pregnancy,” Dr. Nabhani says, “and that presents challenges because it limits how we approach kidney stone diagnosis and treatment.”

For example, doctors detect and treat kidney stones using X-rays and anesthesia — both which can be inadvisable during pregnancy. And acquiring an infection associated with a kidney stone during pregnancy can be “problematic” for the fetus, Dr. Nabhani adds.

None of which means that women with or at risk for a kidney stone should avoid pregnancy; doctors can still safely and effectively treat kidney stones in pregnant patients. All the same, Dr. Nabhani reiterates, “These are things to be aware of.”

Prevention is universal

Fortunately, preventing kidney stones is pretty straightforward — and it’s the same whether you’re male or female.

• Stay hydrated: Dr. Nabhani says that 50% of kidney stones result from dehydration. So, drink up! Water is Dr. Nabhani’s beverage of choice, though he also gives coffee and tea the nod, with this caveat: “They’re diuretics, so they can dehydrate you. But chase them with water and you’ll be okay.”
• Limit sodium: Excess sodium consumption can force the kidneys to excrete more calcium in the urine, increasing the risk for calcium-based kidney stones. Dr. Nabhani recommends capping sodium intake at 2,000 mg per day. And that, he says, is “a matter of making your own food as much as you can, reading food labels and trying not to eat a lot of processed or fast food.”
• Moderate protein: High-protein diets can also promote excessive calcium excretion, which is why Dr. Nabhani advises consuming a “kidney-healthy” amount — 60 to 70 grams per day. “You don’t have to go vegetarian, but limiting meat intake to one small-ish serving per day is a good idea,” he says, defining “small-ish” as roughly the size of your cell phone.
• More produce: Much of the research into diet and kidney stones finds that eating more produce can increase urine volume by half a liter per day, diluting its solute concentration and reducing the risk of kidney stone formation. “So, all things being equal,” Dr. Nabhani says, “just increasing your fruit and vegetable intake goes a long way toward prevention.”

If this sounds like garden-variety health advice, that’s because it is. “And that’s the point I always make to my patients,” Dr. Nabhani concludes. “The recommendations we’re making are good for your kidneys, your heart, hypertension, diabetes prevention — everything else. It’s a win-win.”

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