title: Clinical features of small contraction wave recorded by an external tocodynamometer.
abstract: Clinical features of the small contraction wave recorded by a guardring tocodynamometer were examined retrospectively. This study included 578 patients and 6363 cardiotocographs ranging from 20 to 42 weeks of gestation. The small wave was observed in 7.5% of the cardiotocographs examined, and the rate of small-wave appearance in each gestational week tended to decrease gradually as the pregnancy progressed. This was not observed after 41 weeks of gestation. The small wave-positive group had relatively poor obstetric parameters and fetal outcome, and the small wave was frequently observed in cases of effective beta 2-stimulant intravenous infusion for the treatment of preterm labor. These results suggest that the small wave represents some degree of contractility and is ominous in general; however, the appearance of the wave does not lead to a poor prognosis in preterm labor if large phasic contractions can be abolished by beta 2-stimulant treatment.
authors.affiliation: Department of Obstetrics and Gynecology, Saga Medical School, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kawarabayashi
authors.forename: K
authors.initials: K
authors.lastname: Kuriyama
authors.forename: T
authors.initials: T
authors.lastname: Kishikawa
authors.forename: H
authors.initials: H
authors.lastname: Sugimori
mesh_terms: D000328:Adult; D005260:Female; D005865:Gestational Age; D006340:Heart Rate, Fetal; D006801:Humans; D007752:Obstetric Labor, Premature / Q000188:drug therapy / Q000503:physiopathology*; D009774:Obstetrics / Q000295:instrumentation; D011247:Pregnancy; D012189:Retrospective Studies; D014590:Uterine Contraction