In female anatomy, the vestibular bulbs, bulbs of the vestibule or clitoral bulbs are two elongated masses of erectile tissue typically described as being situated on either side of the

vaginal opening In mammals, the vagina is the elastic, muscular part of the female genital tract. In humans, it extends from the vestibule to the cervix. The outer vaginal opening is normally partly covered by a thin layer of mucosal tissue called the hymen ...

. They are united to each other in front by a narrow median band. Some research indicates that they do not surround the vaginal opening, and are more closely related to the

clitoris The clitoris ( or ) is a female sex organ present in mammals, ostriches and a limited number of other animals. In humans, the visible portion – the glans – is at the front junction of the labia minora (inner lips), above the ope ...

than to the vestibule.

Structure

Research indicates that the vestibular bulbs are more closely related to the

than to the vestibule because of the similarity of the trabecular and erectile tissue within the clitoris and bulbs, and the absence of trabecular tissue in other genital organs, with the erectile tissue's trabecular nature allowing engorgement and expansion during

sexual arousal Sexual arousal (also known as sexual excitement) describes the physiological and psychological responses in preparation for sexual intercourse or when exposed to sexual stimuli. A number of physiological responses occur in the body and mind as ...

. Ginger et al. state that although a number of texts report that they surround the vaginal opening, this does not appear to be the case and tunica albuginea does not envelop the erectile tissue of the bulb. The vestibular bulbs are homologous to the bulb of penis and the adjoining part of the corpus spongiosum of the male and consist of two elongated masses of erectile tissue. Their posterior ends are expanded and are in contact with the greater vestibular glands; their anterior ends are tapered and joined to one another by the pars intermedia; their deep surfaces are in contact with the inferior fascia of the urogenital diaphragm; superficially, they are covered by the

bulbospongiosus The bulbospongiosus muscle (bulbocavernosus in older texts) is one of the superficial muscles of the perineum. It has a slightly different origin, insertion and function in males and females. In males, it covers the bulb of the penis. In femal ...

Physiology

During the response to

the bulbs fill with blood, which then becomes trapped, causing

erection An erection (clinically: penile erection or penile tumescence) is a physiological phenomenon in which the penis becomes firm, engorged, and enlarged. Penile erection is the result of a complex interaction of psychological, neural, vascular, ...

. As the clitoral bulbs fill with blood, they tightly cuff the vaginal opening, causing the vulva to expand outward. This puts pressure on nearby structures that include the corpus cavernosum of clitoris and crus of clitoris, inducing pleasure. The blood inside the bulb's erectile tissue is released to the circulatory system by the spasms of orgasm, but if orgasm does not occur, the blood will exit the bulbs over several hours.

Additional images

File:EdSim Clitoris anatomy.jpg, The sub-areas of the clitoris—areas include clitoral glans, body, crura. The vestibular bulbs and corpora cavernosa are also shown. File:Vulva and Clitoris 1.png, Clitoral bulbs under the labia and on both sides of the vaginal entrance

References

External links

* - "The Female Perineum: Muscles of the Superficial Perineal Pouch" * {{DEFAULTSORT:Vestibular Bulbs Mammal female reproductive system