Every vagina has its own odor. Most women describe it as a musky or slightly sour smell, which are both normal. While most vaginal odors are caused by bacteria, sometimes your urine can also affect the smell.

An ammonia-like smell in your vagina might be alarming at first, but it’s usually nothing serious. Keep reading to learn what might be causing it and how you can manage it.

Before diving into possible causes of an ammonia odor in your vagina, it’s important to understand how and why your body produces ammonia. Your liver is responsible for breaking down proteins. Ammonia, which is toxic, is a result of this process. Before leaving your liver, ammonia is broken down into urea, which is far less toxic.

Urea is released into your blood stream and moved to your kidneys, where it leaves your body when you urinate. That faint smell of ammonia that’s common in urine is a result of ammonia byproducts in urea.

Bacterial vaginosis

Your vagina contains a fragile balance of good and bad bacteria. Any disruption to this balance can cause too much bad bacteria, leading to an infection called bacterial vaginosis. The CDC reports that bacterial vaginosis is the most common vaginal infection in women between the ages of 15 and 44. Many women with bacterial vaginosis report noticing a fishy smell coming from their vagina, but others smell a more chemical odor, similar to ammonia.

Additional symptoms of bacterial vaginosis include:

  • pain, itching, or burning
  • burning sensation when urinating
  • thin, watery discharge that’s white or gray
  • itchiness on the outside of your vagina

Some cases of bacterial vaginosis go away on their own, but others require antibiotics. You can reduce your risk of getting bacterial vaginosis by not douching, which can upset the balance of good and bad bacteria in your vagina. Also, you can reduce your risk of bacterial vaginosis by using condoms consistently.

Pregnancy

Many women report noticing an ammonia-like smell early in their pregnancy. It’s unclear why this happens, but it’s likely related to changes in diet or infection.

Certain foods, such as asparagus, can affect the smell of your urine. When pregnant, some women start to crave foods they don’t usually eat. Doctors aren’t exactly sure why this happens.

If you eat a new food that causes your urine to smell different, you might notice the smell lingering due to dried urine around your vagina or in your underwear. This usually isn’t a cause for concern, but you may want to keep a food diary to help you track down which food is causing it.

A 2014 study also found that pregnant women report an increased sense of smell during their first trimester. That means you may just be noticing the normal smell of your urine.

In some cases, the unusual smell could be the result of bacterial vaginosis. While this usually isn’t serious in women who aren’t pregnant, bacterial vaginosis is linked to premature birth and low birth weights. If you’re pregnant and notice any symptoms of bacterial vaginosis, contact your doctor immediately.

Dehydration

Your urine is a combination of water and waste products, including urea. When your body is dehydrated, the waste products in your urine are more concentrated. This can cause your urine to have a strong ammonia smell as well as a darker color. When this urine dries on your skin or underwear, you might notice a lingering ammonia smell.

Other symptoms of dehydration include:

  • fatigue
  • dizziness
  • increased thirst
  • decreased urination

Try drinking more water throughout the day and see if the smell goes away. If your other dehydration symptoms go away but you’re still smelling ammonia, contact your doctor.

Sweat

According to the Cleveland Clinic, 99 percent of sweat is water. The other 1 percent is made up of other substances, including ammonia. Your sweat is released through two types of sweat glands, called eccrine and apocrine glands. Apocrine glands tend to be more common in areas with a lot of hair follicles, including your groin.

While sweat from both types of glands is odorless, sweat from apocrine glands is more likely to smell when it comes into contact with bacteria on your skin. In addition to all those apocrine glands, your groin contains lots of bacteria, making it a perfect environment for odors, including those that smell like ammonia.

Sweating and bacteria are both crucial parts of your overall health, but you can limit the smell they create by:

  • thoroughly cleaning your vulva with warm water, paying close attending to folds in your labia
  • wearing 100 percent cotton underwear, which makes it easier for sweat to evaporate off your body
  • avoiding tight pants, which make it harder for sweat to evaporate off your body

Menopause

After menopause, many women develop postmenopausal atrophic vaginitis. This causes thinning of your vaginal wall as well as inflammation. This can make you prone to urinary incontinence, which can leave the area around your vagina smelling like ammonia. It also increases your risk of developing vaginal infections, such as bacterial vaginosis.

Other symptoms of postmenopausal atrophic vaginitis include:

  • dryness
  • burning sensation
  • decreased lubrication during sex
  • pain during sex
  • itching

Some symptoms can be easily managed by using a natural, water-based lubricant. You can also ask your doctor about hormone replacement therapy. In the meantime, wearing a panty liner can help to absorb any urine leaks throughout the day.

While several things can cause your vagina to smell like ammonia, there are a few things you can do to help prevent it, including:

  • not douching, as it disrupts the balance of bacteria in your vagina
  • drinking plenty of water, especially when exercising
  • wiping from front to back to reduce your risk of getting a bacterial infection
  • wearing 100 percent cotton underwear and loose-fitting pants
  • regularly washing your vulva with warm water
  • wearing panty liners or frequently changing your underwear if you’re prone to urine leakage

If you notice the smell of ammonia around your vagina, it could be due to extra sweat, urine, or an infection. If the smell doesn’t go away with regular rinsing and drinking more water, contact your doctor. You may need a prescription to help treat an underlying infection.