BACKGROUND: The measurement of the frequency of uterine contractions has not been useful for reducing the rate of @entity3152 in randomized trials. Nonetheless, ambulatory monitoring of contractions continues to be used in clinical practice. METHODS: We assessed the frequency of uterine contractions as a predictor of the risk of spontaneous @entity3152 before 35 weeks of gestation. We enrolled @entity1 with singleton pregnancies between 22 and 24 weeks of gestation. The @entity1 used a contraction monitor at home to record contraction frequency twice daily on 2 or more days per week from enrollment to delivery or 37 weeks of gestation. RESULTS: We obtained 34,908 hours of successful monitoring recordings from 306 @entity1 . Although more contractions were recorded from @entity1 who delivered before 35 weeks than from @entity1 who delivered at 35 weeks or later, we could identify no threshold frequency that effectively identified @entity1 who delivered preterm @entity1 . The sensitivity and positive predictive value of a maximal hourly frequency of contractions of four or more between 4 p.m. and 3:59 a.m. were 9 percent and 25 percent, respectively, at 22 to 24 weeks and 28 percent and 23 percent at 27 to 28 weeks. Other proposed screening tests, such as digital and ultrasound evaluations of the cervix and assays for fetal fibronectin in cervicovaginal secretions, also had low sensitivity and positive predictive value for @entity3152 . CONCLUSIONS: Although the likelihood of @entity3152 increases with an increased frequency of uterine contractions, measurement of this frequency is not clinically useful for predicting @entity3152 .

Frequency of uterine contractions and the risk of spontaneous XXXX .

@entity1 :: ('9606', 'Species') :: ['infants', 'women'] @entity3152 :: ('MESH:D007752', 'Disease') :: ['preterm delivery', 'preterm labor']
@entity3152 :: (MESH:D007752,Disease) :: ['preterm delivery']
