Vaginal discharge is a fluid that flows from the vagina. It is produced by glands located in the vaginal wall and the cervix. One of the most common causes of outpatient gynecology visits is the presence of abnormal vaginal discharge. Different types of diseases can cause these abnormal vaginal secretions. In most cases, they are due to infections caused by bacteria, fungi, parasites, and viruses.

This article will review everything you should know about vaginal discharge, including the different types of vaginal discharge and how to differentiate normal secretions from pathological ones.

What is normal vaginal discharge?

Normal vaginal discharge is made of cells, fluids, and bacteria. Its role is to lubricate and protect the vagina. A healthy vaginal discharge consistency can range from watery to sticky, and the color can range from clear to whitish. It also has a slight odor that isn’t strong smelling. The vaginal discharge appearance varies from woman to woman but can also change in the same woman during her life. For example, depending on the menstrual cycle period, the appearance and quantity of the secretions vary. The amount of discharge increases during the ovulation period, sexual arousal, breastfeeding, and pregnancy. Women in menopause or the one on birth control also experience a change in their vaginal discharge.

What is abnormal vaginal discharge?

An abnormal vaginal discharge occurs when there is a change of :

  • color (yellow, green, grey, brown, or blood-stained)
  • consistency (thick or thin)
  • odor (strong smell or fish-like odor)

There are also related  signs and symptoms, such as :

  • itching in the vulva and vagina,
  • pain (abdominal, vaginal, or during sex)
  • redness and lesions (blisters) in the genital areas (vulva, vagina)

What are the causes of abnormal vaginal discharge?

Abnormal vaginal discharge is usually caused by an infection or anything that can disrupt the vagina’s balance of normal bacteria. The aspect of the discharge varies depending on the cause. Here are the most common causes of abnormal vaginal discharge.

Bacterial vaginosis

It usually occurs when there is an imbalance in the vaginal flora, leading to the excessive development of bacteria naturally found at a low level in the vagina. Several risk factors promote this phenomenon (vaginal douching, sexual practices, such as receiving oral sex, unprotected sex, many sexual partners, etc.) Bacterial vaginosis causes thin discharge with a fishy smell. The color is usually gray, white, or green.


Chlamydia is a common bacterial, sexually transmitted infection. It is asymptomatic in 61% of women (1). This infection is caused by Chlamydia Trachomatis, which has an affinity for the endocervix (2). Chlamydia causes vaginal discharge that is yellow or milky white with a foul-smelling. Women infected by chlamydia also experience other symptoms such as pain during sex, pelvic pain, vaginal discomfort, and sometimes bleeding between periods or after intercourse. Left untreated, the infection can spread and reach the fallopian tubes and cause Pelvic Inflammatory Disease (P.I.D.), which is a medical emergency.


Gonorrhea is the second most common sexually transmitted infection. It is also asymptomatic in more than half of women. (3)  This condition is caused by Neisseria Gonorrhoeae, which also has an affinity for the endocervix. (2) The vaginal discharge is abundant, purulent, and has a yellowish or greenish color. There are also other symptoms, such as irritation, redness, and genital swelling.  The symptoms of chlamydia and gonorrhea are often similar, although there are milder in chlamydia.

Vaginal yeast infection

Vaginal yeast infection is the second most common infection that affects the vagina. The germ involved is Candida Albicans. The symptom of yeast infection is a thick, white, odor-free vaginal discharge that looks like cottage cheese. Sometimes the discharge may also be watery. Women also experience itching and discomfort in the vagina and vulva.


It is a sexually transmitted infection caused by Trichomonas Vaginalis. You can contract trichomoniasis during unprotected sex with an infected person. Trichomoniasis is asymptomatic in most cases. When symptomatic, it is characterized by abundant vaginal discharge of yellowish or greenish color, foamy (like soapy water) with a bad smell. It is often associated with signs of discomfort, such as genitals swelling, redness, itching, and pain during sex.

Genital Herpes

Genital herpes is a sexually transmitted disease caused by  Herpes Simplex Virus 1 (HSV-1) and Herpes Simplex Virus 2 (HSV-2) but usually by HSV-2.  The vaginal discharge associated with genital herpes is clear or whitish in color,  thick, or cloudy liquid with a fishy smell that tends to increase after sex. The discharge may also have traces of blood.  Genital herpes often causes blisters and sores in the genital areas.

Tumor or cancer

A tumor may also cause vaginal discharge, even though it is rare. For example, women can experience a watery vaginal discharge in cervical cancer, brownish or blood-tinged, and abundant. There is often a context of pelvic pain and bleeding after sex.

Others vaginal discharge origins

A foreign body in the vagina like a retained tampon can alter the normal vaginal flora, leading to abnormal vaginal discharge. Vaginal secretions are usually more abundant, and there is an inflammation of the genital areas.

A vaginal allergic reaction may also cause vaginal discharge. This is usually due to perfumes or other ingredients in feminine hygiene products and synthetic underwear made with polyester or rayon. In rare cases, a sexual partner’s sperm is the cause of the allergy.

Key Points

  • Normal vaginal discharge is a physiological secretion that protects and lubricates the vagina.
  • Normal vaginal discharge is usually clear or white. The appearance may vary depending on the physiological changes of the body (menstrual cycles, pregnancy, and menopause).
  • Abnormal vaginal discharge is a frequent reason for outpatient gynecology visits.
  • The causes of abnormal vaginal discharge are numerous. Infectious causes (bacteria, parasites, fungi, viruses) are the most common.
  • The appearance of vaginal discharge differs depending on the cause.

Types of vaginal discharge



  1. Huai, P., Li, F., Chu, T., Liu, D., Liu, J., And Zhang, F. (2020). Prevalence of genital Chlamydia trachomatis infection in the general population: a meta-analysis. B.M.C. Infectious Diseases, 20(1), 1-8.
  2. Kataria, U., Siwach, S., And Chhillar, D. (2015). Study of the causes of vaginal discharge among sexually active females in age group of 20-45 years: A hospital-based study in B.P.S. Government Medical College for Women, Khanpur Kalan, District Sonipat, Haryana, India. International Archives of Integrated Medicine, 2(4), 1/4.
  3. Ferreyra, C., Osborn, J., Moussy, F., Alirol, E., Lahra, M., Whiley, D., Shafer, W., Unemo, M., Klausner, J., Kelly Cirino, C., and Wi, T. (2020). Developing target product profiles for Neisseria gonorrhoeae diagnoses in the context of antimicrobial resistance: An expert consensus. PLoS ONE, 16(9), 1-15.


Spread the love

Tagged in:

About the Author

Hermione M.

My name is Hermione. I am the founder of WomenH and I write about women's health, wellness, mental health, and personal growth. I created this platform to inspire women to take care of themselves mentally, physically, and emotionally to become their best selves. Thank you for stopping by.

View All Articles