Author/Editor		Rudel, D; Pajntar, M
Title		Contractions of the cervix in the latent phase of labour
Type		članek
Source		Contemp Rev Obstet Gynaecol
Vol. and No.		Letnik 11, št. 4
Publication year		1999
Volume		str. 271-9
Language		eng
Abstract		According to recent findings the uterine cervix plays an adive role during the progress of labour. Some consider this to be determined by biochemical processes, but others understand that smooth muscle cell contradions adively influence the course of labour. A hypothesis exists that contradions of circular muscle cells contribute to the construction of the cervical canal, while longitudinal cell contradions contribute to cervical canal dilatation. Different investigations have shown the independent activity of the cervix from that of the uterine corpus myometrium in the latent phase of labour Mechanically registered contractions and electrically registered cervical muscle cell electromyographic (EMG) activity may help to explain clinically observed situations where the cervix does not dilate as expected, or a previously soft cervix becomes suddenly rigid during the latent phase of labour. An EMG signal derived from the cervix has the same general characteristics as a smooth muscle EMG. A permanent background EMG activity indicates continuous muscle cell activity and is a sign of an unripe cervix. It might represent prolonged muscular activity, which helps to keep the fetus in the uterus during pregnancy but disrupts the onset of labour. Low-frequency EMG bursts appear periodically synchronously or asynchronously with uterine contractions. In the early latent phase they are often superimposed on the permanent background activity. Two different EMG signal patterns indicate two different contraction mechanisms and a different origin of the EMG activity in the cervix.
Descriptors		CERVIX UTERI MUSCLE, SMOOTH LABOR ELECTROMYOGRAPHY MUSCLE CONTRACTION BIOCHEMISTRY