{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T12:08:22Z","timestamp":1785499702017,"version":"3.56.0"},"reference-count":16,"publisher":"Elsevier BV","issue":"6","license":[{"start":{"date-parts":[[2006,12,1]],"date-time":"2006-12-01T00:00:00Z","timestamp":1164931200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.elsevier.com\/tdm\/userlicense\/1.0\/"},{"start":{"date-parts":[[2006,12,1]],"date-time":"2006-12-01T00:00:00Z","timestamp":1164931200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.elsevier.com\/legal\/tdmrep-license"}],"content-domain":{"domain":["ajog.org","clinicalkey.com","clinicalkey.com.au","clinicalkey.es","clinicalkey.fr","clinicalkey.jp","elsevier.com","sciencedirect.com"],"crossmark-restriction":true},"short-container-title":["American Journal of Obstetrics and Gynecology"],"published-print":{"date-parts":[[2006,12]]},"DOI":"10.1016\/j.ajog.2006.03.063","type":"journal-article","created":{"date-parts":[[2006,6,13]],"date-time":"2006-06-13T10:20:58Z","timestamp":1150194058000},"page":"1564-1570","update-policy":"https:\/\/doi.org\/10.1016\/elsevier_cm_policy","source":"Crossref","is-referenced-by-count":24,"title":["A prospective masked observational study of uterine contraction frequency in twins"],"prefix":"10.1016","volume":"195","author":[{"given":"Roger B.","family":"Newman","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jay D.","family":"Iams","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anita","family":"Das","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert L.","family":"Goldenberg","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paul","family":"Meis","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Atef","family":"Moawad","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Baha M.","family":"Sibai","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Steve N.","family":"Caritis","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Menachem","family":"Miodovnik","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard H.","family":"Paul","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mitchell P.","family":"Dombrowski","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Molly","family":"Fischer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"78","reference":[{"key":"10.1016\/j.ajog.2006.03.063_bib1","series-title":"National vital statistics reports. Vol. 52, No. 10","article-title":"Births: final data for 2002","author":"Martin","year":"2003"},{"key":"10.1016\/j.ajog.2006.03.063_bib2","doi-asserted-by":"crossref","first-page":"742","DOI":"10.1016\/S0002-9378(98)70075-4","article-title":"Outcomes of very low birth weight twins cared for in the National Institute of Child Health and Human\u00a0Development Neonatal Research Network's intensive care units","volume":"179","author":"Donovan","year":"1998","journal-title":"Am J Obstet Gynecol"},{"key":"10.1016\/j.ajog.2006.03.063_bib3","first-page":"129","article-title":"The changing epidemiology of multiple births in the United States","volume":"101","author":"Russell","year":"2003","journal-title":"Obstet Gynecol"},{"key":"10.1016\/j.ajog.2006.03.063_bib4","doi-asserted-by":"crossref","first-page":"456","DOI":"10.1016\/S0002-9378(94)70211-X","article-title":"The risks confronting twins: a national perspective","volume":"170","author":"Powers","year":"1994","journal-title":"Am J Obstet Gynecol"},{"key":"10.1016\/j.ajog.2006.03.063_bib5","first-page":"661","article-title":"The contribution of singletons, twins and triplets to low birth weight, infant mortality, and handicap in the United States","volume":"37","author":"Luke","year":"1992","journal-title":"J Reprod Med"},{"key":"10.1016\/j.ajog.2006.03.063_bib6","first-page":"773","article-title":"Detection of preterm labor by ambulatory\u00a0monitoring of uterine activity: a preliminary report","volume":"68","author":"Katz","year":"1986","journal-title":"Obstet Gynecol"},{"key":"10.1016\/j.ajog.2006.03.063_bib7","first-page":"517","article-title":"the Uterine Activity in Pregnancy Working Group. Diurnal and gestational patterns of uterine activity in normal human pregnancy","volume":"83","author":"Moore","year":"1994","journal-title":"Obstet\u00a0Gynecol"},{"key":"10.1016\/j.ajog.2006.03.063_bib8","doi-asserted-by":"crossref","first-page":"1271","DOI":"10.1016\/0002-9378(93)90379-W","article-title":"Relationship of circadian rhythms of uterine activity\u00a0with term and preterm delivery","volume":"168","author":"Germain","year":"1993","journal-title":"Am J Obstet Gynecol"},{"key":"10.1016\/j.ajog.2006.03.063_bib9","doi-asserted-by":"crossref","first-page":"530","DOI":"10.1016\/0002-9378(86)90596-X","article-title":"Uterine activity during pregnancy in ambulatory patients: comparison of singleton and twin gestations","volume":"154","author":"Newman","year":"1986","journal-title":"Am J Obstet Gynecol"},{"key":"10.1016\/j.ajog.2006.03.063_bib10","first-page":"695","article-title":"The influence of fetal number on antepartum uterine activity","volume":"73","author":"Newman","year":"1989","journal-title":"Obstet Gyencol"},{"key":"10.1016\/j.ajog.2006.03.063_bib11","first-page":"56S","article-title":"Uterine activity characteristics in multiple gestations","volume":"76","author":"Garite","year":"1990","journal-title":"Obstet Gynecol"},{"key":"10.1016\/j.ajog.2006.03.063_bib12","doi-asserted-by":"crossref","first-page":"250","DOI":"10.1056\/NEJMoa002868","article-title":"Frequency of uterine contractions and the risk of spontaneous preterm delivery","volume":"346","author":"Iams","year":"2002","journal-title":"N Engl J Med"},{"key":"10.1016\/j.ajog.2006.03.063_bib13","doi-asserted-by":"crossref","first-page":"567","DOI":"10.1056\/NEJM199602293340904","article-title":"The length of the cervix and the risk of spontaneous premature delivery. National Institute of Child Health and Human Development Maternal Fetal Medicine Unit Network","volume":"334","author":"Iams","year":"1996","journal-title":"N Engl J Med"},{"key":"10.1016\/j.ajog.2006.03.063_bib14","doi-asserted-by":"crossref","first-page":"643","DOI":"10.1016\/0029-7844(96)00035-X","article-title":"The preterm prediction study: fetal fibronectin testing and spontaneous preterm birth","volume":"87","author":"Goldenberg","year":"1996","journal-title":"Obstet Gynecol"},{"key":"10.1016\/j.ajog.2006.03.063_bib15","first-page":"152-A","article-title":"The Preterm Prediction Study: comparison of the cervical score and Bishop score for the prediction of spontaneous preterm birth","volume":"4","author":"Newman","year":"1997","journal-title":"J Soc Gynecol Invest"},{"key":"10.1016\/j.ajog.2006.03.063_bib16","doi-asserted-by":"crossref","first-page":"837","DOI":"10.2307\/2531595","article-title":"Comparing the area under two or more correlated receiver operating characteristic curves: a non-parametric approach","volume":"44","author":"DeLong","year":"1988","journal-title":"Biometrics"}],"container-title":["American Journal of Obstetrics and Gynecology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.elsevier.com\/content\/article\/PII:S0002937806004509?httpAccept=text\/xml","content-type":"text\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/api.elsevier.com\/content\/article\/PII:S0002937806004509?httpAccept=text\/plain","content-type":"text\/plain","content-version":"vor","intended-application":"text-mining"}],"deposited":{"date-parts":[[2025,9,11]],"date-time":"2025-09-11T10:20:41Z","timestamp":1757586041000},"score":1,"resource":{"primary":{"URL":"https:\/\/linkinghub.elsevier.com\/retrieve\/pii\/S0002937806004509"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2006,12]]},"references-count":16,"journal-issue":{"issue":"6","published-print":{"date-parts":[[2006,12]]}},"alternative-id":["S0002937806004509"],"URL":"https:\/\/doi.org\/10.1016\/j.ajog.2006.03.063","relation":{},"ISSN":["0002-9378"],"issn-type":[{"value":"0002-9378","type":"print"}],"subject":[],"published":{"date-parts":[[2006,12]]},"assertion":[{"value":"Elsevier","name":"publisher","label":"This article is maintained by"},{"value":"A prospective masked observational study of uterine contraction frequency in twins","name":"articletitle","label":"Article Title"},{"value":"American Journal of Obstetrics and Gynecology","name":"journaltitle","label":"Journal Title"},{"value":"https:\/\/doi.org\/10.1016\/j.ajog.2006.03.063","name":"articlelink","label":"CrossRef DOI link to publisher maintained version"},{"value":"article","name":"content_type","label":"Content Type"},{"value":"Copyright \u00a9 2006 Mosby, Inc. All rights reserved.","name":"copyright","label":"Copyright"}]}}