MEASUREMENT OF INTRA-VAGINAL AND INTRA-UTERINE PRESSURES DURING HUMAN COITUS BY RADIO-TELEMETRY

Abstract

Summary. Intra-vaginal and intra-uterine pressure changes during human coitus were monitored by the use of a pressure-sensitive radiopill. Pressure was found to be negative in the vagina during intromission and male orgasm but became positive during female orgasm. In the uterus, the pressure changes were minimal during male orgasm but increased markedly during female orgasm to a positive pressure of 40 cm H2O, followed by a sharp fall after orgasm to a negative pressure of 26 cm H2O. The reliability of these results is discussed in relation to their possible significance in the pattern of sperm transport, and it is suggested that the final negative pressure following female orgasm may effect an `insuck' of the cervical mucus with its entrapped spermatozoa.