The urethral sponge is composed of erectile tissue; during arousal, it becomes swollen with blood, compressing the urethra, helping prevent urination during sexual activity (along with the pubococcygeus muscle).
Additionally, the urethral sponge contains the Skene's glands, which may be involved in female ejaculation.
The urethral sponge encompasses sensitive nerve endings, and can be stimulated through the front wall of the vagina. Some women experience intense pleasure from stimulation of the urethral sponge and others find the sensation irritating. The urethral sponge surrounds the clitoral nerve, and since the two are so closely interconnected, stimulation of the clitoris may stimulate the nerve endings of the urethral sponge and vice versa. Some women enjoy the rear-entry position of sexual intercourse for this reason, because the penis is often angled slightly downward and can stimulate the front wall of the vagina, and in turn the urethral sponge.
Relation with the G-spot
The urethral sponge is an area in which the G-spot (Gräfenberg Spot) may be found. Although the G-spot may exist, it has been doubted by various researchers. A team at The King's College in London, the biggest study on the G-spot's existence thus far, and involving 1,800 women, found no proof that the G-spot exists. The authors of the study concluded that the "G-spot" may be a figment of people's imagination, which has been encouraged by magazines, sex therapists and suggestive therapeutics. Other studies, using ultrasound, have found physiological evidence of the G-spot in women who report having orgasms during intercourse.
- Cornforth, Tracee (17 July 2009). "The Clitoral Truth. Interview with author and sexologist Rebecca Chalker". About.com. Archived from the original on 3 December 2010. Retrieved 21 April 2010.
- "G-spot 'doesn't appear to exist'". BBC News. 4 January 2010. Retrieved 27 May 2010.
- "The Journal of Sexual Medicine - Wiley Online Library". Wiley.com. Archived from the original on 17 February 2009. Retrieved 7 September 2013.
- See page 98 for the 2009 King's College London's findings on the G-spot and page 145 for ultrasound/physiological material with regard to the G-spot. Ashton Acton (2012). Issues in Sexuality and Sexual Behavior Research: 2011 Edition. ScholarlyEditions. ISBN 978-1464966873. Retrieved 24 January 2014.
- Gravina GL, Brandetti F, Martini P, et al. (2008). "Measurement of the Thickness of the Urethrovaginal Space in Women with or without Vaginal Orgasm" (PDF). J Sex Med. 5 (3): 610–8. doi:10.1111/j.1743-6109.2007.00739.x. hdl:2108/8798. PMID 18221286.