SARS-CoV-2的母婴垂直传播

The Potential Vertical Transmission of SARS-CoV-2

孕妇感染新型冠状病毒(SARS-CoV-2)使各类妊娠并发症发生风险增加,且在部分病例中可引起胎盘病变。目前SARS-CoV-2感染与胎盘病变之间的直接关系尚未明确,但已有研究证实SARS-CoV-2能够跨越胎盘屏障,引起母婴间垂直传播。虽然发病率低,但是正确认识SARS-CoV-2的母婴垂直传播,对孕期保健和母婴安全依然非常重要。临床上一旦确诊胎盘功能变化以及对胎儿生长有影响,应及时采取相应措施尽可能减少胎儿死亡和其他严重的母婴并发症。本研究综合分析已发表的国际文献和2022年美国和加拿大病理学会、欧洲病理学会年会8组胎盘和部分死产胎儿病理研究资料,总结阐述现有的科学证据,以期为理解SARS-CoV-2感染对孕妇的影响提供参考,并针对SARS-CoV-2的母婴垂直传播问题,提出未来研究方向,即:SARS-CoV-2是如何跨过胎盘感染胎儿;垂直传播发生在妊娠的早期、中期还是晚期;病毒感染以后胎盘功能异常,为什么对大部分孕妇没有影响或者没有明显的影响;不同的病毒变异株、不同类型的疫苗接种对感染孕妇的影响是否不同。

The presence of SARS-CoV-2 infection in pregnant women has potentially been associated with increased maternal morbidity and various placental abnormalities in a subset of patients. At present, the direct relationship between SARS-CoV-2 infection and placental lesions is not clear, but studies have confirmed that SARS-CoV-2 can cross the placental barrier and cause vertical transmission between mother and baby. Understanding the mechanisms underlying SARS-CoV-2 vertical transmision is critical for antenatal care and maternal-neonatal safety despite of its low occurence.Once the change of placental function and its impact on fetal growth are confirmed clinically, corresponding measures should be taken in time to minimize fetal death and other serious complications of mother and child. This study intends to review and analyze the published international literatures and the pathological research data of eight groups of placenta and some stillborn fetuses published on the 2022 annual meeting of USCAP and European Congress of Pathology, summarize and elaborate the existing scientific evidence, with a view to providing reference for understanding the impact of SARS-CoV-2 on pregnant women, and propose the future research direction for the vertical transmission of SARS-CoV-2: how does SARS-CoV-2 infect the fetus across the placenta;does vertical transmission occur in the early, middle or late pregnancy;after virus infection, placental function is abnormal, why do most pregnant women have no or no obvious influence;do different virus variants and different types of vaccination have different effects on infected pregnant women.