A critical investigation of the measurement of the force required to dilate the human uterine cervix.
A system for objectively analysing the forces of dilation of the human uterine cervix was devised using a force sensing device linked to a BBC microcomputer. The computer program allowed easy recording, storage and analysis of force/time curves obtained from the passage of tapered dilators through the cervix. A new design of dilator gave a smoother force/time curve. These force/time curves were analysed. Six indices: peak force, end force, area to peak, area to end the ratio of the peak and end forces recorded from the passage of the two largest and two smallest dilators, were compared. Area measurement was subject to artefact and rejected. Peak and end force measurements gave the best separation between parous and nulliparous patients. The peak force was judged to be the better as it was found to be easier to define than end force.
Kenyon
N J
NJ
Department of Obstetrics and Gynaecology, Northern General Hospital, Sheffield, UK.
Stevens
J C
JC
Stewart
P
P
Black
M M
MM
Clifford
A
A
D055592:Biophysical Phenomena; D001703:Biophysics; D002584:Cervix Uteri / Q000502:physiology*; D004106:Dilatation / Q000295:instrumentation; D005260:Female; D006801:Humans; D012815:Signal Processing, Computer-Assisted; D013997:Time Factors; D014160:Transducers, Pressure