Kidney Pain While Pregnant: Causes and Treatment

Published July 20th, 2022 by Bridget Reed
Fact Checked by
Camille Freking
Medically Reviewed:
Dr. Angel Rivera

Growing pains, cramps, and muscle soreness are a rite of passage when it comes to pregnancy. But how can you tell if some of this pain is normal or a cause for concern?

Kidney pain while pregnant can result from a serious underlying condition, so knowing the difference between this and normal pregnancy pains is essential.

Here’s everything you need to know, including the causes and remedies.

What Causes Kidney Pain While Pregnant?

The pain you might feel in your kidneys while pregnant is an indirect sensation from the pregnancy itself.

The feelings you’re experiencing are most likely due to kidney stones.

Kidney stones are hard deposits of minerals and salts that can form inside your kidneys.

They form when urine contains a lot of crystal-forming substances like calcium, uric acid, and oxalate. The fluid in your urine might not be able to dilute it well, leading to a mineral build-up in your kidneys.

Kidney stone formation can happen to anyone, but it’s estimated to affect about nine percent of women by age 70, and the risk of developing them is more common when pregnant.

Pregnant people are more likely to form kidney stones due to the bladder being squeezed by the growing fetus, frequent urination, and decreasing bladder control. 

As a result, dehydration during pregnancy is common, which is one of the main risk factors for kidney stones to develop. 

What Do Kidney Stones Feel Like?

Kidney stones won’t typically cause symptoms unless they move around the kidney or into the ureter (the tube that connects the kidneys to the bladder).

If a kidney stone moves into the ureters, it can be super painful as it blocks urine flow.

Kidney stone pain can be pretty tough to bear, and it often presents as a severe, sharp pain in the side. If you feel flank pain and back pain below the ribs, you could be experiencing kidney stones. 

You might also feel some pain radiating into the lower abdomen or groin, as well as abdominal pain that comes in waves and fluctuates in intensity.

Non-physical signs of kidney stones might include pink or brown urine or urine that smells foul. You might also feel a persistent need to urinate, nausea, vomiting, fever, or chills.

How To Treat Kidney Stones

While kidney stones can be pretty frustrating, the good news is that most smaller ones pass through the body independently with time.

However, larger stones might need treatment.

Surgery

Percutaneous nephrolithotomy can surgically remove a large kidney stone using small instruments inserted through an incision in the back. It can take one to two days to recover in the hospital from this treatment.

For smaller stones, a doctor might insert a ureteroscope into the urethra.

A ureteroscope is a small, lighted tube with a camera on the end that can allow doctors to locate and remove small kidney stones with special instruments. Doctors may also recommend the insertion of a stent to aid in the passing of stones. 

Sound Waves

Yep, you read that right. For certain kidney stones, a healthcare provider may recommend extracorporeal shock wave lithotripsy, or ESWL.

This treatment uses sound waves that vibrate and break up the kidney stone into smaller pieces that can pass through urine.

The procedure can cause moderate pain and last up to an hour. Additionally, this method may not be recommended for pregnant individuals because it is unclear how it can affect the fetus.

Preventing Kidney Stones

The best way to treat kidney stones is to prevent them in the first place.

And while pregnancy itself doesn’t increase your risk of developing them, you can tackle certain indirect risks head-on to reduce your odds.

Stay Hydrated

One of the main culprits that lead to a kidney stone is dehydration.

When pregnant, you need to drink more water than the average person, as it plays a vital role in forming a healthy placenta and ensuring the baby receives the necessary nutrients.

Not to mention, water is used to form amniotic fluid later in pregnancy.

Pregnant women should drink at least eight to 12 glasses of water a day, and a doctor might recommend that you drink even more if you have a history of kidney stones. 

You might also want to avoid foods or beverages that cause dehydration, like coffee. Caffeine can increase your urine output and make it easier to become dehydrated. Finally, avoid strenuous exercise that causes excessive sweating to keep your water supply in check.

Switch Up Your Diet

Certain foods can also increase your risk of kidney stones and kidney pain.

Calcium-oxalate stones are the most common type of kidney stone, forming from too much oxalate in the body. For that reason, you might benefit from eating fewer high-oxalate foods.

Try cutting back on:

  • Bran flakes
  • Spinach
  • Beets
  • Rhubarb
  • Potato chips
  • French fries
  • Nuts or nut butter

With that said, oxalate is unavoidable, even in a healthy diet. Increasing calcium intake and reducing oxalate intake might be recommended.

Talk to your doctor before using calcium supplements, as these can increase your risk of kidney stones.

Additionally, you’ll want to try to cut back on high sodium foods that can contribute to dehydration. Consider a salt substitute for your meals, like Mrs. Dash.

Other Causes of Kidney Pain While Pregnant

If you’re feeling kidney pain during pregnancy, there’s a very high likelihood that it’s related to kidney stones.

However, there are some other reasons why you might be feeling discomfort.

For one, you may have a urinary tract infection or UTI. Hormonal and physical changes occur rapidly during pregnancy, which can affect the composition of urine and the size of kidneys.

These can contribute to increased susceptibility to urinary tract infections in pregnancy.

Symptoms of a UTI include strong and persistent urges to urinate, cloudy urine, or pelvic pain. Contact your doctor or gynecologist if you experience the common symptoms of a UTI to get treatment as soon as possible.

They will do a urine culture (urine test) to see if bacteria are causing your pain. UTIs can cause serious complications and preterm labor (premature labor), so treatment is important.

You might also confuse kidney pain for other types of common pregnancy pains. Round ligament pain in the lower abdomen can result from the uterine lining expanding to make room for the fetus. 

Your body releases progesterone which loosens the tendons and ligaments that hold your growing uterus.

Contraction pain can also occur in the second and third trimesters, a severe sensation that feels like pressure in the pelvis.

In Conclusion

Kidney pain during pregnancy can result from several triggers, but kidney stones are the most common.

Kidney stones are mineral deposits in the kidneys that can block the lower urinary tract and cause immense discomfort.

Kidney stones typically form from dehydration, common during pregnancy, as the body requires more water than the average person.

You can treat kidney stones through surgery or sound wave procedures, but the best method is to avoid them altogether by staying hydrated and avoiding sodium-heavy foods.

Kidney pain during pregnancy might also result from a UTI, round ligament expansion, or contractions.

The bottom line is that if you feel severe, worrying pain, you should immediately reach out to your doctor or OB-GYN (obstetrics and gynecology doctor).

References, Studies and Sources:

Kidney stones - Symptoms and causes | The Mayo Clinic

Shock Wave Lithotripsy | CHAM

Dehydration During Pregnancy | American Pregnancy Association

Urinary Tract and Kidney Infections during Pregnancy | Children's Hospital of Philadelphia