Obstet Gynecol. 2021 Aug 1;138(2):e65-e90. doi: 10.1097/AOG.0000000000004479.
Preterm birth is among the most complex and important challenges in obstetrics. Despite decades of research and clinical advancement, approximately 1 in 10 newborns in the United States is born prematurely. These newborns account for approximately three-quarters of perinatal mortality and more than one half of long-term neonatal morbidity, at significant social and economic cost (1-3). Because preterm birth is the common endpoint for multiple pathophysiologic processes, detailed classification schemes for preterm birth phenotype and etiology have been proposed (4, 5). In general, approximately one half of preterm births follow spontaneous preterm labor, about a quarter follow preterm prelabor rupture of membranes (PPROM), and the remaining quarter of preterm births are intentional, medically indicated by maternal or fetal complications. There are pronounced racial disparities in the preterm birth rate in the United States. The purpose of this document is to describe the risk factors, screening methods, and treatments for preventing spontaneous preterm birth, and to review the evidence supporting their roles in clinical practice. This Practice Bulletin has been updated to include information on increasing rates of preterm birth in the United States, disparities in preterm birth rates, and approaches to screening and prevention strategies for patients at risk for spontaneous preterm birth.
早产是产科领域最复杂且重要的挑战之一。尽管经过数十年的研究和临床进展，但在美国，每10名新生儿中仍约有1名早产。这些新生儿约占围产期死亡率的四分之三，以及长期新生儿发病率的一半以上，造成了巨大的社会和经济成本（1 - 3）。由于早产是多种病理生理过程的共同终点，因此有人提出了早产表型和病因的详细分类方案（4, 5）。一般来说，约一半的早产是由自发性早产临产引起的，约四分之一是由胎膜早破（PPROM）引起的，其余四分之一的早产是因母体或胎儿并发症等医学指征而有意为之。美国的早产率存在显著的种族差异。本文档的目的是描述预防自发性早产的危险因素、筛查方法和治疗方法，并综述支持它们在临床实践中作用的证据。本实践公告已更新，纳入了美国早产率上升、早产率差异以及对有自发性早产风险患者的筛查和预防策略等相关信息。
