The glands in a healthy vagina produce mucus. Normal vaginal mucus is slightly acidic and is comprised mostly of water, mucin and albumin, a water-soluble protein found in the tissue of mammals. Lactobacilli, beneficial bacteria, flourish in a normal vagina and help to maintain a healthy pH. The cervix also produces mucus. The characteristics of cervical and vaginal mucus change in response to many factors. The outflow of sloughed-off cells and vaginal mucus is commonly referred to as discharge.
Healthy Vaginal Discharge
Normal, healthy vaginal discharge varies in amount, consistency, color and odor, depending on many factors. Hormones, for example, can influence several characteristics of cervical and vaginal mucus. In this way, vaginal discharge can be defined as "normal," relative to a woman's menstrual cycle or other hormone-shifting events like pregnancy or menopause. In general, normal vaginal discharge ranges from clear to white or slightly yellow, is odorless or has a mild, inoffensive odor. It can range from minimal to copious in amount and from watery to sticky in consistency. The components of normal vaginal mucus provide lubrication, protect from harmful microorganisms and maintain healthy pH.
An imbalance of vaginal flora can cause abnormal changes in vaginal discharge. Overgrowth of the organism Candida albicans can cause thick, copious, curd-like, white vaginal discharge. This discharge can cause itching and is also referred to as a yeast infection. Certain bacteria are also present in a healthy vagina. Bacterial overgrowth can result in infection and cause changes in vaginal discharge. Proliferation of the bacterium Gardnerella vaginalis, for example, causes the common infection Bacterial vaginosis, or BV. The discharge typical of BV is thin and sticky with a gray or yellow cast and an unpleasant "fishy" odor.
Sexually Transmitted Infections
Sexually transmitted infections can cause abnormal vaginal mucus and discharge. Trichomoniasis vaginalis is a parasite that can cause foul-smelling, greenish-yellow, frothy vaginal discharge. Gonorrhea, also a sexually transmitted infection, can cause thick, green, pus-like vaginal discharge. Some other STIs, such as herpes and HPV, are not characterized by significant or unusual change in vaginal discharge.
Vaginal discharge during menstruation is obscured by blood flowing from the uterus. It can be normal to notice some spots of blood, ranging in color from light pink to brown, just before and just after the menstrual cycle. At the time of ovulation vaginal discharge is copious, clear, stretchy and can resemble raw egg white. Leukorrhea, or thick, white or yellow vaginal discharge, is common during pregnancy. During and after menopause, a decrease in the volume of vaginal discharge is common.
The state of a woman's vaginal discharge often has consequences to physical and emotional health. The presence of healthy vaginal discharge often also impacts sexual function and self-esteem. Discharge can be preoccupying when there are problems. It is a good idea to speak openly with your doctor or midwife about all of your concerns and to express honestly how it affects you. See your doctor as soon as possible if you experience unusual vaginal discharge, especially if it is accompanied by burning, pain, itching, a foul smell or unusual color. The National Institutes of Health advise seeking immediate help from a physician if an unusual vaginal discharge occurs with pain in the abdomen or pelvis, fever, known or possible exposure to any STD, or symptoms of diabetes.