Vahanian Sevan A, Lavery Jessica A, Ananth Cande V, Vintzileos Anthony
Department of Obstetrics and Gynecology, Winthrop-University Hospital, Mineola, NY.
Department of Obstetrics and Gynecology, College of Physicians and Surgeons, Columbia University, New York, NY.
Am J Obstet Gynecol. 2015 Oct;213(4 Suppl):S78-90. doi: 10.1016/j.ajog.2015.05.058.
We sought to evaluate the extent of the association between placental implantation abnormalities (PIA) and preterm delivery in singleton gestations. We conducted a systematic review of English-language articles published from 1980 onward using PubMed, MEDLINE, EMBASE, CINAHL, LILACS, and Google Scholar, and by identifying studies cited in the references of published articles. Search terms were PIA defined as ≥ 1 of the following: placenta previa, placenta accreta, vasa previa, and velamentous cord insertion. Observational and experimental studies were included for review if data were available regarding any of the aforementioned PIA and regarding gestational age at delivery or preterm delivery. Case reports and case series were excluded. Studies were reviewed and data extracted. The primary outcome was gestational age at delivery or preterm delivery <37 weeks' gestation. Secondary outcomes included birthweight, 1- and 5-minute Apgar scores, neonatal intensive care unit (NICU) admission, neonatal and perinatal death, and small for gestational age. Of the 1421 studies identified, 79 met the defined criteria; 56 studies were descriptive and 23 were comparative. Based on the descriptive studies, the preterm delivery rates for low-lying/marginal placenta, placenta previa, placenta accreta, vasa previa, and velamentous cord insertion were 26.9%, 43.5%, 57.7%, 81.9%, and 37.5%, respectively. Based on the comparative studies using controls, there was decreased pregnancy duration for every PIA; more specifically, there was an increased risk for preterm delivery in patients with placenta previa (risk ratio [RR], 5.32; 95% confidence interval [CI], 4.39-6.45), vasa previa (RR, 3.36; 95% CI, 2.76-4.09), and velamentous cord insertion (RR, 1.95; 95% CI, 1.67-2.28). Risks of NICU admissions (RR, 4.09; 95% CI, 2.80-5.97), neonatal death (RR, 5.44; 95% CI, 3.03-9.78), and perinatal death (RR, 3.01; 95% CI, 1.41-6.43) were higher with placenta previa. Perinatal risks were also higher in patients with vasa previa (perinatal death rate RR, 4.52; 95% CI, 2.77-7.39) and velamentous cord insertion (NICU admissions [RR, 1.76; 95% CI, 1.68-1.84], small for gestational age [RR, 1.69; 95% CI, 1.56-1.82], and perinatal death [RR, 2.15; 95% CI, 1.84-2.52]). In singleton gestations, there is a strong association between PIA and preterm delivery resulting in significant perinatal morbidity and mortality.
我们试图评估单胎妊娠中胎盘植入异常（PIA）与早产之间的关联程度。我们使用PubMed、MEDLINE、EMBASE、CINAHL、LILACS和谷歌学术对1980年以后发表的英文文章进行了系统综述，并通过识别已发表文章参考文献中引用的研究来进行。检索词为PIA，定义为以下至少一项：前置胎盘、胎盘植入、血管前置和帆状脐带附着。如果有关于上述任何一种PIA以及分娩时孕周或早产的数据，则纳入观察性和实验性研究进行综述。排除病例报告和病例系列。对研究进行综述并提取数据。主要结局是分娩时孕周或孕周小于37周的早产。次要结局包括出生体重、1分钟和5分钟阿氏评分、新生儿重症监护病房（NICU）入院、新生儿和围产期死亡以及小于胎龄儿。在识别出的1421项研究中，79项符合既定标准；56项研究为描述性研究，23项为比较性研究。基于描述性研究，低置/边缘性胎盘、前置胎盘、胎盘植入、血管前置和帆状脐带附着的早产率分别为26.9%、43.5%、57.7%、81.9%和37.5%。基于使用对照的比较性研究，每种PIA都会使妊娠持续时间缩短；更具体地说，前置胎盘患者早产风险增加（风险比[RR]，5.32；95%置信区间[CI]，4.39 - 6.45），血管前置患者早产风险增加（RR，3.36；95%CI，2.76 - 4.09），帆状脐带附着患者早产风险增加（RR，1.95；95%CI，1.67 - 2.28）。前置胎盘患者NICU入院风险（RR，4.09；95%CI，2.80 - 5.97）、新生儿死亡风险（RR，5.44；95%CI，3.03 - 9.78）和围产期死亡风险（RR，3.01；95%CI，1.41 - 6.43）更高。血管前置患者围产期风险也更高（围产期死亡率RR，4.52；95%CI，2.77 - 7.39），帆状脐带附着患者也如此（NICU入院[RR，1.76；95%CI，1.68 - 1.84]，小于胎龄儿[RR，1.69；95%CI，1.56 - 1.82]，围产期死亡[RR，2.15；95%CI，1.84 - 2.52]）。在单胎妊娠中，PIA与早产之间存在强烈关联，会导致显著的围产期发病率和死亡率。
