早产是围生医学中的一个重要、复杂而又常见的妊娠并发症,因其围生儿发病率、死亡率和后遗症较足月者显著升高而成为一个世界性的卫生问题。由于对早产认识上的差异,如先兆早产的就医率低,或种族、社会地位、经济状况等多种因素的影响,使报道的早产发生率基本波动在5%~15%之间, Premature birth is an important, complex and common pregnancy complication in perinatal medicine. It has become a worldwide health problem because its perinatal morbidity, mortality and sequelae are significantly higher than those in full-term. Due to differences in understanding of prematurity, such as the low rate of medical treatment for threatened preterm birth, or the impact of various factors such as race, social status and economic status, the reported incidence of preterm birth fluctuates between 5% and 15%