Newman Roger B, Iams Jay D, Das Anita, Goldenberg Robert L, Meis Paul, Moawad Atef, Sibai Baha M, Caritis Steve N, Miodovnik Menachem, Paul Richard H, Dombrowski Mitchell P, Fischer Molly
Department of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, SC, USA.
Am J Obstet Gynecol. 2006 Dec;195(6):1564-70. doi: 10.1016/j.ajog.2006.03.063. Epub 2006 Jun 12.
This study was undertaken to compare uterine contraction frequency in twins versus singletons and to determine if contraction frequency can be an efficient predictor of spontaneous preterm birth in twin gestations.
Fifty-nine twin and 306 singleton gestations were enrolled between 22 and 24 weeks at 11 centers. Contraction frequency was recorded with a home uterine activity monitor (HUAM) 2 or more times per day on 2 or more days per week until delivery or 36-6/7 weeks. Masked HUAM data were interpreted according to standard protocol. Repeated measures analyses were used to determine whether mean or maximum uterine contraction frequency per hour differed between singleton and twin gestations across gestational age, by time of day, and by delivery before 35 weeks or beyond. Uterine contraction frequency was also evaluated by logistic regression and receiver operator characteristic (ROC) curves as tests to predict spontaneous preterm birth.
There were 34,908 hours of HUAM data recorded by the 306 singleton gestations and 5,427 hours by the 59 women with twins. Uterine contraction frequency was significantly greater in twins (P = .002) compared with singletons, regardless of gestational age. Contraction frequency in twins increased significantly with gestational age and time of day (1600-0359 hours); but was not associated with spontaneous preterm birth. Maximum uterine contraction frequency was associated with preterm birth less than 35 weeks but only in the morning (am) recording (0400-1559) and at the 29- to 30-week gestational age interval. This relationship was modest (odds ratio 1-2) and not consistent across gestational age or between the am and afternoon/evening (pm) monitoring sessions. ROC analysis revealed no contraction frequency that efficiently identified twins who delivered prematurely at any 2-week gestational age interval.
Mean uterine contraction frequency was significantly higher for twin gestations than singletons throughout the latter half of pregnancy and between 1600 and 0359 hours but was not higher among twins who delivered less than 35 weeks' gestation. Neither maximum am or pm contraction frequency predicted spontaneous preterm birth less than 35 weeks' gestation in twin pregnancies.
本研究旨在比较双胎妊娠与单胎妊娠的子宫收缩频率，并确定收缩频率是否可作为双胎妊娠自发性早产的有效预测指标。
11个中心招募了59例双胎妊娠和306例单胎妊娠，孕周为22至24周。使用家庭子宫活动监测仪（HUAM）每周至少2天、每天至少2次记录宫缩频率，直至分娩或孕36 - 6/7周。根据标准方案解读盲法处理的HUAM数据。采用重复测量分析来确定单胎和双胎妊娠在不同孕周、一天中的不同时间以及孕周小于35周或大于35周分娩时每小时的平均或最大子宫收缩频率是否存在差异。还通过逻辑回归和受试者工作特征（ROC）曲线评估子宫收缩频率，以预测自发性早产。
306例单胎妊娠记录了34908小时的HUAM数据，59例双胎妊娠记录了5427小时。无论孕周如何，双胎妊娠的子宫收缩频率均显著高于单胎妊娠（P = 0.002）。双胎妊娠的收缩频率随孕周和一天中的时间（16:00 - 03:59）显著增加；但与自发性早产无关。最大子宫收缩频率与孕周小于35周的早产相关，但仅在上午（04:00 - 15:59）记录且在孕29至30周孕周区间。这种关系较弱（优势比为1 - 2），且在不同孕周或上午与下午/晚上监测时段之间不一致。ROC分析显示，在任何2周孕周区间内，没有收缩频率能有效识别早产的双胎妊娠。
在妊娠后半期以及16:00至03:59期间，双胎妊娠的平均子宫收缩频率显著高于单胎妊娠，但在孕周小于35周分娩的双胎妊娠中并不更高。上午或下午的最大收缩频率均不能预测双胎妊娠中孕周小于35周的自发性早产。
