Brown Discharge: 11 Common Causes & When to Worry

Updated in March 2024

Brown discharge may be noted at the end of or after a period, and is a sign that the blood is starting to clot after a few days of heavier flow. The brown color usually indicates older blood, and is a normal findings during the menstrual cycle. However, brown discharge that occurs with other symptoms may be a sign of another health condition, like endometriosis, PCOS or an ovarian cyst. 

Brown discharge may also occur after sex, especially following any vaginal wall irritation. Irritation is more common during phases of hormonal changes, like during menstruation or pregnancy. 

If brown discharge lasts for more than 3 days or if you are also experiencing any discomfort, like itching or pelvic pain, you should see your doctor for assessment and to initiate treatment as needed. Check out what different colors of vaginal discharge mean. 

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What causes brown discharge?

The most common causes of brown vaginal discharge include:

1. End of a period

It is common for period blood to become darker and to reduce in quantity in the last days of menstruation. This may start to slow down and progress to a brown discharge. It is considered to be normal and disappears within 2 to 3 days.

What to do: as this is a normal situation, it is not necessary to undergo any treatment or to see a doctor. However, if this discharge is persistent, increases in quantity or has a foul odor, it is important that you consult a gynecologist. 

2. Changing birth control

It is possible to notice brown discharge after changing birth control. This is the result of hormonal changes caused by this this type of medication. Read more about the side effects of birth control.

What to do: in this case, it is important to adhere to your prescription as instructed by your doctor. The discharge should disappear after a few days. If the brown discharge continues, however, you should see your prescriber for further assessment and to determine the need to suspend or change the medication again

Also recommended: 9 Birth Control Options: Advantages, Disadvantages & Side

3. Cervical irritation

The cervix is a very sensitive area and normal procedures, such as the pap test, or increased sex, may cause brown discharge

What to do: No specific treatment is necessary, because there is usually very little brown discharge with no other symptoms. Keeping the area clean and dry may be enough to resolve this discharge in less than 2 days. However, it is important to avoid sex until the discharge has disappeared.

4. Pelvic inflammatory disease

Pelvic inflammatory disease refers to an inflammation in a woman's internal reproductive organs, and can be caused by conditions like endometritis, salpingitis, bacterial vaginosis, or inflammation of the ovaries. These conditions can cause dark discharge, pelvic pain and discomfort during sex. The discharge can appear during or after menstruation, or a few days or weeks after being infected with an STI.

Also recommended: Pelvic Pain: 12 Causes & What to

What to do: After ordering tests to identify what is causing the inflammatory disease, the doctor may indicate the use of oral antibiotics or a topical ointment for application in the vagina. Anti-inflammatory drugs and medications for fever may also be recommended. If there is no improvement in symptoms within 3 days, the doctor can swap the medications for others. Sex is not advised until you finish the treatment, as these diseases can be transmitted sexually.

5. Ovarian cyst 

Ovarian cysts can cause uterine bleeding before or after menstruation, and this mixed with the woman's natural secretions can come out as a brown discharge. Cysts often also cause other symptoms, such as pain during ovulation or during/after sex, spotting outside of a period, weight gain and difficulty getting pregnant.

Read more about the symptoms of ovarian cysts and the common doubts many women have. 

What to do: Specific treatment isn’t always necessary, especially in young women as cysts are considered to be normal. Your doctor may recommend the use of birth control to manage symptoms. In more severe cases, the ovary may need to be removed to prevent further complications such as torsion of the ovary or cancer. 

6. Polycystic ovarian syndrome

Polycystic ovary syndrome can cause dark discharge due of the presence of uterine blood. Other common symptoms include irregular periods, acne and the appearance of thick facial or body hair.

What to do: Treatment can be completed using specific contraceptive pill recommended by the doctor. These can help to regulate cycles and control hormonal fluctuations, noting that not all contraceptive pills are suitable. 

7. Uterine fibroid

A uterine fibroid is a benign tumor that forms in the muscular lining of the uterus. Generally, they do not cause symptoms, but depending on the size, location and size of the myoma, you may experience brown discharge, abdominal pain, cramping and bleeding outside a period.

What to do: you should consult your gynecologist for assessment. The doctor will perform a physical examination and order imaging, such as a transvaginal ultrasound, to confirm a diagnosis and start the most appropriate treatment. Treatment can range from just medical monitoring to the use of hormone therapy or an IUD. 

8. Ectopic pregnancy

An ectopic pregnancy occurs when the embryo develops outside the uterus, most commonly in the fallopian tubes. It can cause brown discharge, intense cramping on only one side of the abdomen, pain that worsens with movement, vaginal bleeding, pain during sex, dizziness, nausea, vomiting or fainting.

What to do: If you notice symptoms of an ectopic pregnancy, you should proceed to the nearest emergency room for testing and diagnosis. Treatment usually involves surgical removal of the embryo. 

9. Uterine cancer

Uterine cancer can cause brown vaginal discharge, as well as other symptoms like bleeding before, during or after menstruation, and pain in the pelvic area after sex.

What to do: If you suspect something isn't right, you consult your doctor for assessment. Cancer can be ruled out with tests like a pap test or colposcopy. If confirmed, appropriate treatment will depend on the stage of cancer diagnosed, and may include brachytherapy, radiation, or surgical removal of the uterus.

10. Endometriosis

Endometriosis is a condition that affects many women. It is characterized by the growth of uterine tissue outside of the uterus, like in the ovaries or intestines. Some more common symptoms include brown discharge, intense pelvic pain, heavy period flow, pain with sex, and even difficulty urinating or pooping. 

Learn more about endometriosis symptoms and how symptoms can vary depending on where uterine cells migrate to.

What to do: Treatment for endometriosis should be guided by a doctor and individual to each woman. It is important to have regular follow-ups with your gynecologist. Some treatment options include the use of IUDs, hormonal therapy and surgery. 

11. Sexually-transmitted infections (STIs)

Some STIs, like gonorrhea or chlamydia, can also cause brown discharge. These cases occur more frequently following unprotected sex, and are normally accompanied by other symptoms like pain with urination, the sensation of pressure in the pelvic are and bleeding with sex. 

Learn more about the most common STIs and how they are treated. 

What to do: STIs normally require treatment with antibiotic, therefore it is important to consult your doctor if you suspect infection. 

Can brown discharge be a sign of pregnancy?

Usually, brown discharge is not a sign of pregnancy. It is more common to see a small amount of pinkish discharge in the beginning of pregnancy, which indicates that the embryo has attached itself into the lining of the uterus. Learn more about brown discharge during pregnancy and when it is normal.

However, if a pregnant woman has a dark fluid similar to menstruation and brown discharge, this may indicate blood loss through the vagina and requires assessment. You should especially seek medical attention if it has a foul smell or other symptoms like abdominal pain, itching or heavy bleeding. This change may indicate, among other possibilities, ectopic pregnancy. 

Read about early pregnancy symptoms that can occur along with brown discharge.

When to worry

Go to a gynecologist when the brown vaginal discharge:

  • Lasts more than 3 days
  • Is accompanied by other symptoms such as abdominal pain, foul smell or itching
  • Occurs with bright red bleeding

In these cases, the doctor will diagnose the problem by examining the discharge and inserting the vaginal speculum to assess the inside of the vagina. Based on findings, appropriate treatment will then be recommended. 

When is it normal?

Brown discharge is normal in the following situations:

  • During adolescence
  • After sex during pregnancy
  • In the first few days after menstruation
  • With hormonal changes
  • Changes in the contraceptive method

However, if there is a lot of discharge or if it lasts for more than 3 days, you should see a doctor for assessment.

How to prevent vaginal discharge

To prevent dark vaginal discharge, avoid using vaginal douches and wash the external vagina every day while bathing or after sex. Underwear should be cotton-based to prevent moisture in the area as well as prolonged use of shorts and tight jeans, as these promote increased sweat and the spread of micro-organisms that cause infections.