Vaginal lubrication

Vaginal lubrication is a naturally produced fluid that lubricates the vagina. Vaginal lubrication production increases significantly during sexual arousal in anticipation of sexual intercourse. Vaginal dryness is the condition in which this lubrication is insufficient, and sometimes artificial lubricants are used to augment it. Without sufficient lubrication, sexual intercourse can be painful. The vaginal lining has no glands, and therefore the vagina must rely on other methods of lubrication. Plasma from the vaginal walls due to vascular engorgement is considered to be the chief lubrication source, and the Bartholin's glands, located slightly below and to the left and right of the introitus (vaginal opening), also secrete mucus to augment vaginal wall secretions. Near ovulation, cervical mucus provides additional lubrication.

Vaginal lubrication fluid is a plasma transudate which diffuses across the vaginal wall. Composition varies with the length of arousal.

During arousal, vaginal lubrication, also sometimes called "arousal fluid", is produced. This is clear, thin, and slippery. It typically only lasts up to an hour. It can sometimes be confused with cervical mucus.

The human vagina is serviced by nerves that respond to vasoactive intestinal polypeptide (VIP). As a result, VIP induces an increase in vaginal blood flow accompanied by an increase in vaginal lubrication. The findings suggest that VIP may participate in the control of the local physiological changes observed during sexual arousal: genital vasodilation and an increase in vaginal lubrication. Neuropeptide Y is also involved in producing it.

Insufficient lubrication or vaginal dryness can cause dyspareunia, which is a type of sexual pain disorder. While vaginal dryness is considered an indicator for sexual arousal disorder, vaginal dryness may also result from insufficient excitement and stimulation or from hormonal changes caused by menopause (potentially causing atrophic vaginitis), pregnancy, or breast-feeding. Irritation from contraceptive creams and foams can also cause dryness, as can fear and anxiety about sexual intimacy. Vaginal dryness can also be a symptom of Sjögren syndrome (SS), a chronic autoimmune disorder in which the body destroys moisture-producing glands.

Certain medications, including some over-the-counter antihistamines, as well as life events such as pregnancy, lactation, menopause, aging or diseases such as diabetes, will inhibit lubrication. Medicines with anticholinergic or sympathomimetic effects will dry out the mucosal or "wet" tissues of the vagina. Such medicines include many common drugs for allergenic, cardiovascular, psychiatric, and other medical conditions. Oral contraceptives may also increase or decrease vaginal lubrication.

In seemingly rare cases, selective serotonin reuptake inhibitors (SSRIs) have been reported to cause a long-lasting iatrogenic disorder known as post-SSRI sexual dysfunction, the symptoms of which include reduced vaginal lubrication in females.

Vaginal dryness affects 3-43% of women, and it is more common after menopause. Post-menopausal women produce less vaginal lubrication and reduced estrogen levels may be associated with increased vaginal dryness.