Endometriosis is a chronic condition in which endometrial tissue similar to that found in your uterus grows outside your uterus. This causes pain and other symptoms.

Vaginal discharge is fluid produced by your vagina and cervix. It helps keep your vagina:

  • clean
  • moisturized
  • protected from bacteria

The following changes in your vaginal discharge often indicate an underlying concern, such as an infection or a health condition:

  • color
  • smell
  • consistency

While endometriosis doesn’t usually cause an increase in vaginal discharge, it can sometimes cause changes in the way your discharge looks.

In this article, we’ll explore the relationship between endometriosis and vaginal discharge, including when it’s time to schedule a visit with a healthcare professional.

In most cases, endometriosis does not cause significant changes in the amount or consistency of vaginal discharge. In fact, only one small, old 1980 study linked endometriosis to increased vaginal discharge.

However, endometriosis may cause changes in the color of vaginal discharge due to menstrual irregularities. Spotting that occurs outside of menstruation because of endometriosis can appear as pink or brown tinted discharge.

Endometrial tissue that grows outside your uterus and bleeds into your discharge can make your discharge appear in these colors:

  • pink
  • brown
  • black

Healthy vaginal discharge appears as a clear or white fluid with a mild odor. As the menstrual cycle progresses throughout the month, it can also change in consistency.

Changes in the color of your vaginal discharge, along with other symptoms, may indicate an underlying health condition such as endometriosis. For example, endometriosis can cause:

  • Pink discharge. Pink discharge generally indicates the presence of fresh blood. Endometriosis itself can cause irregular bleeding, or it can be linked to other potential causes of pink discharge. For example, irregular menstrual spotting and ovarian cysts, both of which can be caused by endometriosis, can produce pink discharge.
  • Brown discharge. Brown discharge is usually caused by the oxidation of blood. Unlike pink discharge, brown discharge happens with blood that takes longer to exit your body. Endometriosis can sometimes cause brown-tinted discharge from trapped endometrial tissue that’s unable to shed. Atypical bleeding patterns that accompany endometriosis can also cause brown discharge.
  • Black discharge. Black discharge, like brown discharge, happens with oxidized blood that takes a longer time to leave your body. Endometriosis can cause black discharge if there’s endometrial tissue causing a blockage within your vaginal cavity. Black discharge can also appear from endometrial tissue that’s trapped but still produces blood.

Endometriosis does not usually cause a change in the smell or texture of your discharge. However, a 2020 research review suggested that having endometriosis can increase your chance of developing lower genital tract infections, many of which can change your vaginal discharge’s:

  • color
  • smell
  • texture

According to the National Institutes of Health (NIH), pain and infertility are the most common symptoms of endometriosis. Other symptoms of endometriosis may include:

Endometriosis pain tends to be more severe than regular period pain and often feels like extreme period cramps. Pain that accompanies endometriosis can spread:

  • beyond your uterus
  • to your lower back
  • down your legs

Endometriosis pain can even occur outside of menstruation, such as during sex or bowel movements.

Schedule an appointment with a healthcare professional if you’re having vaginal discharge that’s different from your normal discharge in its:

  • color
  • smell
  • texture

While changes in vaginal discharge are not always caused by endometriosis, they can indicate other underlying health conditions that require treatment.

It’s a good idea to also schedule an appointment with a gynecologist as soon as possible if you experience any other symptoms of endometriosis, such as:

  • spotting
  • irregular periods
  • painful intercourse

In most cases, endometriosis does not have a significant impact on your vaginal discharge’s:

  • amount
  • consistency
  • smell

However, endometriosis does cause menstrual irregularities, which can in turn cause vaginal discharge to sometimes appear:

  • pink
  • brown
  • black

It’s important to remember that endometriosis is not the only cause of changes in vaginal discharge. For this reason, any new or concerning symptoms — especially new or worsening pain — should always be addressed by a healthcare professional or gynecologist.