[Uterine activity and premature delivery. Review of the literature].

OBJECTIVE

This paper reviews the recent literature on uterine activity during gestation with term and preterm delivery.

METHODS

A review of the literature on uterine activity during gestation with term and preterm delivery was conducted by searching Medline file from 1990 to the present, using the key terms "uterine activity", "uterine monitoring", "preterm delivery", "term delivery". Additional references were accessed by cross referencing the bibliographie of the articles obtained through this search.

RESULTS AND CONCLUSIONS

Contractions are infrequent in normal pregnancy. The mean 24-hour frequency of uterine contractions increase progressively with advancing gestational age. A strong diurnal rhythm is present from 24 weeks to the term with surge of contractions at night. These uterine activity noctural surges precede term delivery. These surges are lost in women who deliver prematurely. These studies suggest that early identification of increase in uterine activity is not the most appropriate intervention for prediction of preterm delivery. The reason lies in a flawed contraction-based theory of the pathogenesis of prematurity.