|Classification and external resources|
Vaginal discharge is the biological fluid secreted from the vagina. While most discharge is normal and can reflect the various stages of the menstrual cycle, some discharge can be a result of an infection.
Nonpathological vaginal discharge ranges in pH from 3.8 to 4.2 and is typically white or clear in color, though it can be yellowish. Nothing is visible under a microscope in a vaginal wet mount and treatment with KOH does not give off an odor, which could indicate pathology. It is produced by cervical and vaginal glands.
Vaginal discharge amounts vary as the menstrual cycle progresses. Ovulation can increase discharge. Menopause or low estrogen levels can cause a decrease in discharge.
In neonates, vaginal discharge sometimes occurs in the first few days after birth. This is due to exposure to estrogen while in utero. Neonatal vaginal discharge may be white or clear with a mucous texture, or it may be bloody from normal transient shedding of the endometrium.
During pregnancy, vaginal discharge volume can increase.
Vaginal discharge may increase due to stress or sexual arousal.
Pathological discharge can occur in a number of conditions, including infections and imbalances in vaginal flora or pH. Unusual vaginal discharge may also be idiopathic (the cause is not determined). Diagnosing the cause of abnormal vaginal discharge can be difficult, though a potassium hydroxide test or vaginal pH analysis may be used. When abnormal discharge occurs with burning, irritation, or itching on the vulva, it is called vaginitis.
In bacterial vaginosis, co-occurring symptoms include a fishy odor that worsens during menstruation or after vaginal sex. In a vaginal yeast infection (candidiasis), abnormal discharge may be accompanied with itching and burning. Trichomoniasis can cause a foul odor, itching, light bleeding (spotting), and painful urination. Other bacterial infections, such as those caused by Streptococcus, Staphylococcus, or E. coli may cause itching.
Color, texture, and volume
The color and texture of vaginal discharge can indicate pathology. In bacterial vaginosis, discharge can appear thin, gray, or white, increase in volume, and is adherent. In yeast infections, discharge is described as resembling cottage cheese. Trichomoniasis causes greenish-yellow, adherent, frothy discharge and can cause an increase in discharge. Bacterial infections can cause discharge containing pus.
Potassium hydroxide test
The potassium hydroxide test assess whether or not a fishy odor is given off when vaginal discharge is exposed to the strong base. In bacterial vaginosis it is almost always positive, and it may be positive in trichomoniasis infections.
The pH of vaginal discharge may change depending on the disease present. Normally, the pH of vaginal discharge is between 3.8 and 4.2. In bacterial vaginosis, trichomoniasis, and bacterial infections, it is raised above 4.5, becoming more alkaline (basic). In candidiasis, it is below 4.5.
A microscopic examination of vaginal discharge may indicate pathology. In candidiasis, a potassium hydroxide preparation can show hyphae and buds of the fungus. In bacterial vaginosis and trichomoniasis, a saline wet mount will show clue cells and trichomonads, respectively. Bacterial vaginosis may also cause white blood cells and clumps of bacteria to be visible in the discharge. In bacterial infections, a large number of white blood cells will be seen under the microscope.
- "Vaginal itching and discharge – Adult and adolescent: MedlinePlus Medical Encyclopedia". www.nlm.nih.gov. Retrieved 2015-10-30.
- Hoffman, Barbara; Schorge, John; Schaffer, Joseph; Halvorson, Lisa; Bradshaw, Karen; Cunningham, F. (2012-04-12). Williams Gynecology, Second Edition. McGraw Hill Professional. ISBN 9780071716727.