Cervical contractions: the response of the cervix to oxytocic stimulation in the latent phase of labour.
OBJECTIVE
To assess the cervical response to myometrial activity in early labour.


METHODS
Prospective observational study.


METHODS
Women requiring oxytocin stimulation in induced and spontaneous labours.


METHODS
A teaching hospital in Birmingham.


METHODS
Simultaneous comparison of the cervical response to myometrial contractions was made on a cycle by cycle basis to deduce the properties of the cervix in early labour.


RESULTS
Sixty-seven patients have been monitored, of whom 63 had satisfactory cervimetry data. Thirty (47.6%) women exhibited cervical contractions in response to myometrial activity. This response was only observed at dilatations up to 4 cm. The change in behaviour coincides with the transition from latent to active phases of dilatation. The length of the latent phase of labour was significantly longer in those women who exhibited cervical contractions (P < 0.001), although the active phase was similar in the two groups (P > 0.1). The group without cervical contractions exhibited a greater degree of effacement (P < 0.05) and tended to have more dilated cervices (P < 0.01) than those who showed cervical contractions.


CONCLUSIONS
It is possible for the cervix to contract in early labour. This response may be the result of incomplete preparation of the cervix for the process of dilatation, and is seen during what is recognised as the latent phase in those women in whom the cervix is unaffected and undilated. These properties of the cervix may explain the poor results obtained from oxytocin stimulation of labour in the latent phase.
Oláh
K S
KS
Department of Fetal Medicine, Birmingham Maternity Hospital.
Gee
H
H
Brown
J S
JS
D000328:Adult; D002584:Cervix Uteri / Q000187:drug effects*; D005260:Female; D006801:Humans; D007747:Labor Stage, First / Q000187:drug effects*; D009215:Myometrium / Q000187:drug effects; D010121:Oxytocin / Q000494:pharmacology*; D011247:Pregnancy; D011312:Pressure; D011446:Prospective Studies; D014590:Uterine Contraction / Q000187:drug effects*
D010121:Oxytocin