Vaginas 101

This article is about the birth canal. First, the anus does not have any natural lubrication of its own, and the anal tissues are far more delicate and susceptible to tearing than the vaginal tissues. Isthmus Ampulla Infundibulum Fimbria Ostium. Because the pudendal nerve carries motor and sensory fibers that innervate the pelvic muscles, a pudendal nerve block relieves birth pain. Concerns over average genital appearance or measurements are largely unavailable and make defining a successful outcome for such surgery difficult. Estrogens and progestogens in the menstrual cycles and during premenarche and postmenopause are also similar in female humans and macaques; however, only in macaques does keratinization of the epithelium occur during the follicular phase. Health and Wellness for Life.