Richardson J A, Sutherland I A, Allen D W
Br J Obstet Gynaecol. 1978 Mar;85(3):178-83. doi: 10.1111/j.1471-0528.1978.tb10477.x.
We briefly review instruments that have been used to measure cervical dilatation and describe the development of a new cervimeter. Curves derived from cervical dilatation and intrauterine pressure traces are presented in a form that clearly records the activity of the uterus and the response of the cervix to individual contractions. Our results suggest a new concept for behaviour of the cervix in labour.