Vaginal lubrication

Vaginal lubrication is the naturally produced fluid that reduces friction during sexual intercourse. As a woman becomes sexually aroused, the tissue lining the first inch or so of her vagina (vaginal epithelium" (the walls of the vagina)) begins to swell and exude a slippery fluid (or modified plasma transudate) out through the hundreds of small ducts buried in the lining. These vaginal juices first appear right inside the vagina, and as the woman’s arousal builds, the secretions will run out the opening.

The release of this fluid makes vaginal and vulval play more comfortable. It doubtless evolved to ease both penile-vaginal insertion and the movement of sperm up the vaginal canal, increasing the likelihood of impregnation. Under perfect conditions a highly aroused young woman will lubricate profusely. Certain medications, including some over-the-counter antihistamines, as well as life events such 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 allergic, cardiovascular, psychiatric, and other medical conditions.

Natural lubrication can contain viruses, including HIV/AIDS.