Under normal circumstances, a woman's vagina produces a small amount of fluid, or discharge, that's usually clear but can be cloudy or slightly whitish. In some situations, however, the amount of vaginal discharge might increase and it could be brown or reddish-brown. In many cases, this doesn't signal a problem and could be normal, especially after the end of your menstrual flow. But a brown vaginal discharge might also indicate a problem that needs medical attention.
During the Menstrual Cycle
When you ovulate, a follicle at the surface of the ovary ruptures to release the egg, possibly causing a small amount of bleeding. If this blood flows into the vagina, it could cause a slight brown discharge, which isn't a problem. You might also experience a small amount of uterine bleeding at other times in the cycle, called breakthrough bleeding, which might cause a brownish discharge. Later in the cycle, after menstrual flow ceases, a brownish vaginal discharge might also develop; it's caused by remaining blood and tissue that slowly leave the uterus and pass into the vagina. In most cases, this discharge stops within a few days. In rare cases, a woman might forget to remove a tampon after the end of her menstrual flow. The retained tampon gradually leaks small amounts of old, brownish blood, causing a brown vaginal discharge.
A healthy vagina contains a natural balance of bacteria that normally aren't harmful. But if one type of bacteria grows out of control, possibly after a woman takes an antibiotic, a condition called bacterial vaginosis could develop. This can cause a vaginal discharge, sometimes dark gray or brownish in color, possibly with a greenish tinge. The discharge could be abundant and accompanied by itching, although this isn't always present. Some sexually transmitted infections, such as chlamydia or gonorrhea, might cause a vaginal discharge that can be yellow or brownish-yellow. Although these infections might also cause abnormal bleeding between periods and painful urination, some women have no symptoms, or symptoms might only develop several weeks after the infection begins.
Other Causes for Concern
Although it's uncommon, a brown vaginal discharge might indicate a serious problem. For example, a brown discharge during pregnancy could signal a problem with the placenta; this should be checked immediately by a doctor. If a pregnant woman miscarries, some bleeding from the uterus after the miscarriage could also cause a brown vaginal discharge that slowly subsides. In other rare cases, a brown vaginal discharge could signal the presence of uterine or cervical cancer, which can cause abnormal bleeding from the uterus or cervix, although some women experience no symptoms from these cancers, especially in the early stages.
What to Do
If a brownish discharge lasts for more than a day or two after menstrual flow ceases, seek immediate medical attention to ensure this isn't caused by a retained tampon. A brown vaginal discharge that occurs at other times during the cycle should also be evaluated by your doctor if it doesn't stop on its own in a day or two. If you experience a brown discharge accompanied by irritation or itching of the vulvar area, you might have bacterial vaginosis or another infection; see your doctor to determine the cause and pursue treatment as needed. If you have questions about any type of vaginal discharge, discuss them with your doctor.
- Cleveland Clinic: Menstrual Cycle
- Canadian Family Physician: Vaginal Discharge -- An Approach to Diagnosis and Management
- American College of Obstetricians and Gynecologists: Vaginitis
- Centers for Disease Control and Prevention: Bacterial Vaginosis -- CDC Fact Sheet
- American College of Obstetricians and Gynecologists: Gonorrhea, Chlamydia and Syphilis
- American College of Obstetricians and Gynecologists: Cancer of the Uterus (Endometrial Cancer)
- Centers for Disease Control and Prevention: Cervical Cancer