6 reasons why you may experience brown discharge

• Brown discharge can happen at the beginning and end of your period because the blood oxidizes.
• It can also be a sign of certain STIs like chlamydia and gonorrhea or pelvic inflammatory disease.
• Bloody, brown discharge is also the most common sign of endometrial cancer.

In most cases, brown vaginal discharge is a normal part of your menstrual cycle and not a cause for concern. But sometimes brown discharge can be a sign of an illness or infection that requires medical attention.

Here are six reasons for brown discharge and when to see a doctor.

1. Your period is coming or has just ended

Brown discharge at the beginning of or end of your period usually occurs because the blood is moving more slowly than in the middle of your period. As the blood takes more time to leave the uterus, it oxidizes, turning from a red color to a more brown hue.

How to treat it: Brown discharge at the beginning or end of your period is normal and not typically a cause for concern. But if brown discharge persists for several days or weeks after your period ends or is accompanied by an unpleasant smell, itching, or burning, reach out to your doctor as it could be a sign of infection.

2. Hormonal contraception

Some birth control methods like IUDs or implants that release progestin can cause spotting, irregular menstruation, and brown discharge.

This is more likely with birth control methods that contain little to no estrogen as a lack of estrogen can cause the lining of the uterus to shed a little at a time. And just like at the beginning or end of your period, when blood leaves the uterus slowly it oxidizes and turns brown.

How to treat it: Spotting due to hormonal contraception is not usually a cause for concern and should go away about three months after having an IUD implanted or starting a low-estrogen birth control pill. But if the spotting continues and bothers you, talk with your doctor about your options for switching to a birth control method without this side effect.

3. Sexually transmitted infections

Some sexually transmitted infections, like chlamydia and gonorrhea, can cause vaginal bleeding and brown discharge, says Mel Davis-Hall, GP, medical director at The Lowdown, a contraception prescription platform.

Other symptoms of chlamydia include:

• Pain or burning during urination
• Dull pain in the lower part of your abdomen
• Painful intercourse

Other symptoms of gonorrhea include:

• Bleeding between periods
• Painful urination
• Soreness

In some cases, you may not experience any symptoms with these infections. If you are sexually active, it's important to get tested for STIs often so you can receive proper treatment if you have an STI and don't realize it. Using condoms can also reduce the risk of contracting an STI or passing the infection on to someone else.

How to treat it: Both chlamydia and gonorrhea are treated with antibiotics, which can clear the infection within a couple weeks. It's important to receive proper treatment as soon as possible, as untreated STIs can cause complications, like pelvic inflammatory disease.

4. Pelvic inflammatory disease

Pelvic inflammatory disease (PID) is an infection of the human reproductive organs often caused by bacteria from an untreated STI, like chlamydia or gonorrhea.

Symptoms of PID include:

• Brown vaginal discharge
• Pain in your lower abdomen or uterus
• Fever
• Abnormal bleeding between periods
• Pain during intercourse
• Painful urination

If left untreated, PID can cause severe complications, including infertility or a fatal infection, so if you are experiencing symptoms of PID, seek medical care as soon as possible, says David Kimble, MD, a urogynecologist at the Kimble Center.

How to treat it: PID can be treated with antibiotics, but the potential damage the disease can do to your reproductive organs can not be reversed.

5. Uterine fibroids

Uterine fibroids are noncancerous growths in your uterus that can cause brown discharge and abnormal bleeding, Davis-Hall says.

Other symptoms of uterine fibroids include:

• Pelvic pain during sex
• Urinary problems
• Persistent lower back pain

Uterine fibroids are not usually dangerous, though in some cases they can lead to complications, like blockage of the urinary tract and infertility.

How to treat it: Treatment for uterine fibroids can vary depending on your health history and the severity of your fibroids and symptoms. Common treatment options include:

• Hormone injections
• Hormonal birth control
• Surgery to remove the fibroids

6. Cancer

The presence of brown discharge can indicate either cervical or endometrial cancer, Kimble says. In fact, the most common sign of endometrial cancer is blood in your discharge and unusual vaginal bleeding.

Other signs of endometrial cancer include:

• Painful intercourse
• Difficult or painful urination
• Pelvic pain

Brown discharge is a less prevalent sign of cervical cancer but can occur, Kimble says. Seek medical care If your brown discharge is accompanied by other signs of cervical cancer, including:

• Painful intercourse
• Heavy or prolonged periods
• Bleeding between periods
• Unexplained weight loss
• Weakness and fatigue

How to treat it: Treatment for cervical or endometrial cancer can vary depending on the progression of the disease and your health history. But in general, treatment can include:

• Surgery to remove cancer tissue or reproductive organs
• Radiation
• Chemotherapy
• Hormone therapy

Regular pap smears can help reduce your risk of cervical cancer. And you can decrease your risk of endometrial cancer by maintaining a healthy lifestyle of regular exercise and a nutritional diet.

Estrogen-only hormone therapy can also increase the risk of endometrial cancer, so if you are considering hormone therapy to treat symptoms of menopause, discuss this risk with your doctor.

Insider's takeaway

Brown discharge is often part of a normal menstrual cycle and may be present at the beginning or end of your period when blood leaves the uterus slowly. Spotting or brown discharge can also be a side effect of some types of hormonal birth control.

In some cases, brown discharge can be a sign of a health condition that needs medical treatment, including an STI, pelvic inflammatory disease, or cancer.

If you experience brown discharge that persists for weeks or months and is accompanied by other symptoms, like pelvic pain, an unpleasant smell, painful urination, or painful intercourse, seek medical attention.