- Sweat, changes in vaginal bacteria, and perimenopause may change the odor of your menstrual blood.
- A new, unpleasant smell could also point to an infection or, in some rare cases, cervical cancer.
- If practicing good hygiene and changing menstrual products on time doesn't help, call your doctor.
No doubt about it, your menstrual cycle can cause some pretty unusual smells.
"Menstrual blood includes vaginal mucus and endometrial cells. The combination of those with blood can give off a distinctive odor," says Dr. Yana Markidan, a gynecologist in private practice.
But your blood should typically have a similar odor from month to month, whether it smells more metallic, sweet, or something else. If you notice a new smell during your menstrual cycle, that could suggest something isn't quite right, especially since vaginal odors can be a sign of infection.
Here are the seven most common reasons why your period smells stronger than usual and what to do next.
1. Natural vaginal bacteria mixing with blood
If the mix of bacteria in your vagina (aka your vaginal microbiome) changes, your period blood may take on a different scent.
Common culprits that can disrupt your vaginal microbiome include:
How to treat it: Practicing good vaginal and vulvar hygiene will help keep your vaginal microbiome healthy and help reduce intense smells during your period.
If you already notice a strong odor, try some of the following tips for good vaginal hygiene (and if that doesn't help, consult a doctor):
- Wash your vulva with warm water daily and after sex — just remember, you don't need to wash your vagina.
- Wear breathable cotton underwear.
- Wash new underwear before wearing.
- Avoid douching and scratching anywhere down there.
2. Bacterial vaginosis (BV)
During menses, or your period, you lose "good" bacteria called lactobacilli, Markiden says. This puts you more at risk for infections like bacterial vaginosis (BV).
Markiden says bacterial vaginosis is the most common medical cause of vaginal odor. If you have it, you'll likely notice a fishy smell down there, which may mix with blood during your period to cause an especially pungent odor.
Other symptoms of BV include:
- Burning, especially while urinating or during sex
- Green, gray, or white discharge
- Intense itching
How to treat it: If you think you have BV, you'll need to seek medical aid. Your doctor can prescribe antibiotics to clear up the bacterial infection.
Your doctor may also suggest taking over-the-counter probiotics after the infection clears to help keep your microbiome balanced and lower your chances of developing BV again.
3. Menstrual product left in or on too long
If you've left your tampon, pad, or menstrual cup in for too long, you might notice an overpowering smell of blood.
How often should you change your menstrual products? Well, that can depend on the products you prefer:
- Tampon: At least every eight hours
- Menstrual cup: At least every 12 hours
- Period underwear: At least every 12 hours
- Pad: Every four to eight hours, or as needed
4. Excess sweat
Sweating more than usual is a common symptom of menstruation. And if you sweat between your legs during your period, that can leave your vaginal area smelling something like a dirty gym bag.
Sweat glands in the genital area can amplify the smell of your vaginal microbiome and your skin's natural scent. The combined salt, fat, and bacteria from sweating, when mixed with period blood, can create a potent, odorous mix.
How to treat it: If sweat is to blame, then washing your vulva gently with warm water and mild soap should get rid of the smell.
"During the menstrual cycle, you should use a gentle cleanser without fragrances. Soap can dry the skin and alter the sensitive pH of the vulva, predisposing you to infection," Markidan says.
5. Sexually transmitted infections (STIs)
That said, with an STI, the smell will stick around after your period ends.
- Yellow, green, or other unusually colored discharge, which may mix with blood during your menstrual cycle
- Vaginal bleeding when not on your period
- Pain in your lower abdomen, which could feel similar to menstrual cramps
- Vaginal itching, burning, or pain — especially during urination or vaginal sex
Keep in mind, too, that STIs don't always involve an odor — or any noticeable symptoms.
6. Cervical cancer
Cervical cancer can cause a strong, foul odor in your genital area. This odor, which some people say resembles rotten meat, occurs when your body sheds dead tissue or cancerous cells that then come out through your vagina.
Cervical cancer can cause a heavier flow or longer menstruation, and you may notice the odor becomes more intense during your period.
Globally, cervical cancer is one of the most common types of cancer, though it's less common in the United States due to wider rates of annual Pap smears and vaccinations. It's most frequently diagnosed before menopause, between the ages of 35 and 44.
Common symptoms include:
- Spotting or bleeding between menstrual periods
- Lower back pain, which could feel similar to menstrual cramps
- Pain or bleeding after sex due to tumor growth
- Trouble holding in urine
- Pain and swelling in your legs
- Unintentional weight loss or a decreasing appetite
How to treat it: If you notice these symptoms, make an appointment with your OB-GYN for a Pap smear. Depending on the results, your care team may recommend further testing and a biopsy.
Treatments for cervical cancer include chemotherapy, radiation therapy, surgery, or a combination of these.
This is because your vaginal pH gradually becomes more alkaline and your estrogen levels fluctuate, resulting in heavier and irregular periods that can amplify vaginal odors.
Other signs of perimenopause include:
- Hot flashes, which may involve frequent sweating or a flushed face
- Unpredictable or irregular periods that might be longer or shorter than usual
- Trouble sleeping
- Mood swings
- Thinner vaginal tissue, which can cause vaginal dryness
- Trouble holding in urine
If you prefer not to take hormones, a healthcare professional can offer more information about other treatment options, including vaginal lubrication.
In most cases, an unusual odor during your period doesn't pose a cause for concern. Changing your menstrual products on time and cleaning your vulva gently with water and a mild cleanser can clear up any unwanted odors.
If you notice other symptoms, like nausea or pain, or simply feel something isn't quite right, connect with your doctor as soon as possible. They can help you identify possible causes and recommend the right treatment to help you feel better.