参考文献/References:
[1]DE L t-c, NGBICHI J M, UNFRIED K, et al. WHO recommendations on interventions to improve preterm birth outcomes [J]. [Geneva,Switzerland],WHO,2015 Aug, 2015, 19(1): 234-243.
[2]TYSON J E, PARIKH N A, LANGER J, et al. Intensive care for extreme prematurity - Moving beyond gestational age [J]. New England Journal of Medicine, 2008, 358(16): 1672-1681.
[3]PENNELL C E, JACOBSSON B, WILLIAMS S M, et al. Genetic epidemiologic studies of preterm birth:guidelines for research [J]. American Journal of Obstetrics & Gynecology, 2007, 196(2): 107.
[4]QIN Jia-bi, SHENG Xiao-qi, WANG Hua, et al. Worldwide prevalence of adverse pregnancy outcomes associated with in vitro fertilization/intracytoplasmic sperm injection among multiple births: a systematic review and meta-analysis based on cohort studies [J]. Archives of Gynecology and Obstetrics, 2017, 295(3): 577-597.
[5]BLENCOWE H, COUSENS S, OESTERGAARD M Z, et al. National, regional, and worldwide estimates of preterm birth rates in the year 2010 with time trends since 1990 for selected countries: a systematic analysis and implications [J]. Lancet, 2012, 379(9832): 2162-2172.
[6]沈庆君,王蕴慧,刘颖琳,等.67例紧急宫颈环扎术疗效及影响因素分析 [J],实用妇产科杂志,2014,30(4):270-273.
[7]于松.宫颈环扎术防治早产的疗效 [J].中国实用妇科与产科杂志,2008,24(5):334-336.
[8]张燕,余艳红,任利容,等.宫颈机能不全554例的临床疗效 [J].中华围产医学杂志,2016,19(4):274-277.