多胎妊娠延迟分娩(DID)是指多胎中的一胎(胎儿1)在中孕期，特别是胎龄≤24周时发生流产或早产后，孕妇子宫收缩逐渐减弱，宫口逐渐回缩，甚至宫颈管闭合，若及时采取措施，则可使宫内留存胎儿在宫腔内继续妊娠数天，甚至数周，待其各器官进一步成熟后再娩出。目前，随着女性受孕年龄增加及辅助生殖技术的应用，多胎妊娠发生率逐年上升，多胎妊娠发生胎儿1流产或早产后，对宫内留存胎儿实施DID的成功率也逐渐增高。多胎妊娠DID的适应证包括胎儿1于胎龄≤24周时分娩后，母体宫缩消退，不伴胎膜早破(PROM)、绒毛膜羊膜炎、严重阴道流血、可疑胎盘早剥及其他严重内科与外科合并症，宫内留存胎儿无胎儿宫内窘迫、先天畸形等。目前，DID临床处理措施包括：高位结扎胎儿1脐带，采取宫缩抑制剂抑制母体宫缩、抗菌药物预防母胎感染、宫颈环扎术及对母胎进行严密监护，必要时使用糖皮质激素促胎肺成熟。对宫内留存胎儿实施DID后，分娩时机掌握，非常重要。笔者拟就多胎妊娠胎儿1于胎龄≤24周时分娩后，对宫内留存胎儿实施DID的必要性、适用人群、临床管理、临床处理流程及多胎妊娠DID胎儿妊娠结局等最新研究进展进行阐述，旨在为相关临床研究提供参考。

Definition of delayed interval delivery (DID) in multiple pregnancy is that in the middle pregnancy, especially when gestational age ≤ 24-week, after the abortion or preterm delivery of one of the fetuses (fetus 1) among multiple pregnancy fetuses, the uterine contraction of pregnant women gradually decreases, the uterine orifice gradually retracts, and even cervical canal is closed. If intervention measures are taken in time, the other fetuses can remain in the uterus of pregnant women for several days or even several weeks, and then be delivered after the organs of remaining fetuses being more mature. Due to the increasing of women′s conceptional age and the application of assisted reproductive technology, the occurrence rate of multiple pregnancy has increased gradually. After the abortion or preterm delivery of fetus 1 among multiple pregnancy fetuses, the success rate of DID for the remaining fetuses is also increasing. The indications of DID in multiple pregnancy including: uterine contraction decrease or disappear without premature rupture of membrane (PROM), chorioamnionitis, serious vaginal bleeding, suspected placental abruption or serious complications diseases of internal medicine or surgery of the patients, no intrauterine distress or congenital malformation in the fetus. At present, the clinical treatment measures of DID included ligation of the umbilical cord of the expelled fetus as high as possible, prophylactic use of tocolytic for inhibition of uterine contraction and antimicrobial agents for infections, cervical cerclage and continuous monitorization of the patient, and useing glucocorticoid to promote fetal lung maturity if necessary. It is very important to determine the delivery time after DID for the remaining fetuses. This article focuses on the latest research progresses on necessity, applicable population, clinical management, clinical processes and pregnancy outcomes of DID fetus in multiple pregnancy, in order to provide reference for related clinical research of DID in multiple pregnancy.