COITUS PER URETHRAM is extremely rare; merely 13 cases have been reported in the world literature.1-10 This oddity has been observed mostly in women with either a rigid hymen or vaginal atresia. P. H. Gebhard (personal communication, April, 1965) at the Institute for Sex Research of Indiana University, although not encountering instances of coitus per urethram in women, learned of an unusual case which demonstrated the great elasticity of the human urethra. A man made an artificial hypospadias and progressively enlarged the urethra enabling insertion of another man's penis. W. B. Pomeroy (personal communication, March, 1965) during many years of association with the Institute for Sex Research, encountered examples of urethral masturbation but none of coitus per urethram.
In addition to its rarity, this case report was prompted by the length of time the coitus per urethram was practiced, without any side effects other than urinary incontinence.
Zeigerman JH, Gillenwater JY. Coitus per Urethram and the Rigid Hymen. JAMA. 1965;194(8):909-910. doi:10.1001/jama.1965.03090210073026