PubMed and Web of Science databases were searched between December 1, 2019, and April 30, 2022.
Cohort, cross-sectional, and case-control studies and case series or case reports describing stillbirths or late miscarriages (ie, pregnancy loss occurring between 14 and 22 weeks of gestation, before and after the onset of labor) from mothers with SARS-CoV-2 infection during pregnancy (demonstrated by at least 1 positive real-time reverse transcription-polymerase chain reaction from nasopharyngeal swabs and/or SARS-CoV-2 placental infection). No language restriction was applied; cases with other causes possibly explaining the fetal demise were excluded.
The Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-analysis Of Observational Studies in Epidemiology guidelines were followed. The quality of the case series and case reports was evaluated using the specific Mayo Clinic Evidence-Based Practice Center tool. Maternal and clinical fetal data and placental and fetal virology and histology findings were collected. Data were summarized with descriptive statistics using the World Health Organization criteria to classify disease severity and fetal-neonatal infections.
Data from 184 mothers and 190 fetuses were analyzed. No clear link to maternal clinical severity or fetal malformation was evident. Approximately 78% of fetal demise cases occurred during the second and third trimesters of pregnancy, approximately 6 to 13 days after the diagnosis of SARS-CoV-2 infection or the onset of symptoms. Most placentas (88%) were positive for SARS-CoV-2 or presented the histologic features of placentitis (massive fibrin deposition and chronic intervillositis) previously observed in transplacentally transmitted infections (85%-91%). Of note, 11 fetuses (5.8%) had a confirmed in utero transmitted SARS-CoV-2 infection, and 114 fetuses (60%) had a possible in utero transmitted SARS-CoV-2 infection.
The synthesis of available data showed that fetal demise generally occurs a few days after the infection with histologic placental inflammatory lesions associated with transplacental SARS-CoV-2 transmission and eventually causing placental insufficiency.
方法:PubMed和WebofScience数据库(在2019年12月1日至2022年4月30日之间搜索)。
方法:队列,横断面和病例对照研究,以及描述死产或晚期流产的病例系列或病例报告(即发生在14至22周之间的妊娠损失,分娩前后,分别)来自怀孕期间感染SARS-CoV-2的母亲(通过鼻咽拭子上至少一个阳性的实时逆转录聚合酶链反应证明,和/或胎盘感染SARS-CoV-2)。未应用语言限制;排除可能解释胎儿死亡的其他原因的病例。
方法:遵循PRISMA和MOOSE指南。使用特定的梅奥诊所循证实践中心工具评估病例系列/报告的质量。收集产妇和临床胎儿数据以及胎盘和胎儿病毒学和组织学发现。使用世界卫生组织标准对疾病严重程度和胎儿-新生儿感染进行分类,并对数据进行描述性统计。
结果:分析了来自184名母亲和190名胎儿的数据。与母体临床严重程度或胎儿畸形无明显联系。大约78%的胎儿死亡发生在孕中期和晚期,在诊断为SARS-CoV-2感染或症状开始后的6天和13天,分别。大多数(88%)胎盘对SARS-CoV-2呈阳性,或表现出先前在经胎盘传播的感染中观察到的胎盘炎(大量纤维蛋白沉积和慢性阴道炎)的组织学特征(约85-91%)。11例(5.8%)和114例(60%)胎儿已确认或可能在子宫内传播SARS-CoV-2感染,分别。
结论:现有数据的综合表明,胎儿死亡通常发生在感染后几天,与经胎盘传播SARS-CoV-2相关的组织学胎盘炎性病变并最终导致胎盘功能不全。