Pioneering researchers studied the male and female genitals during coitus (penile-vaginal penetration) with ultrasound technology in 1992[4] and magnetic resonance imaging (MRI) in 1999, mapping the anatomy of the activity and taking images illustrating the fit of male and female genitals.[5] In the research using MRI, researchers imaged couples performing coitus inside an MRI machine.[5] The magnetic resonance images also showed that the penis has the shape of a boomerang, that one third of its length consists of the root of the penis, and that the vaginal walls wrap snugly around it.[5][6] Moreover, MRI during coitus indicate that the internal part of the clitoris[7][8] is stimulated by penile-vaginal movements.[9][4] These studies highlight the role of the clitoris and indicate that what is termed the G-spot may only exist because the highly innervated clitoris is pulled closely to the anterior wall of the vagina when the woman is sexually aroused and during vaginal penetration.[10]
References
^Cosson, Michel; Lambaudie, Eric; Boukerrou, Malik; Lobry, Pierre; Crépin, Gilles; Ego, Anne (2004). "A biomechanical study of the strength of vaginal tissues. Results on 16 post-menopausal patients presenting with genital prolapse". European Journal of Obstetrics, Gynecology, and Reproductive Biology. 112 (2): 201–5. doi:10.1016/S0301-2115(03)00333-6. PMID14746960.
^Buisson, O.; Jannini, E.A. (2013). "Pilot echographic study of the differences in clitoral involvement following clitoral or vaginal sexual stimulation". J. Sex. Med. 10 (11): 2734–2740. doi:10.1111/jsm.12279. PMID23937167.
Further reading
Bondil, P; Costa, P; Daures, JP; Louis, JF; Navratil, H (1992). "Clinical study of the longitudinal deformation of the flaccid penis and of its variations with aging". European Urology. 21 (4): 284–6. doi:10.1159/000474858. PMID1459150.
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