Abstract

Since the first reports of the emergence of the novel coronavirus (severe acute respiratory syndrome corona virus 2 [SARS-CoV-2]) and its associated disease (coronavirus disease 2019 [COVID-19]), concerns remain about whether the virus can be transmitted from the mother to the fetus either during the antepartum period or during the process of labor and delivery. In a previous review involving a small number of cases, 2 placental swabs for polymerase chain reaction (PCR) testing were sent in addition to neonatal and cord blood testing, and the PCR results of the swabs returned negative.1Schwartz D.A. An analysis of 38 pregnant women with COVID-19, their newborn infants, and maternal-fetal transmission of SARS-CoV-2: maternal coronavirus infections and pregnancy outcomes.Arch Pathol Lab Med. 2020; ([Epub ahead of print])Crossref PubMed Scopus (635) Google Scholar Other studies have reported findings of SARS-CoV-2 immunoglobulin M in neonates born to mothers who received a diagnosis of COVID-19 during pregnancy,2Zeng H. Xu C. Fan J. et al.Antibodies in infants born to mothers with COVID-19 pneumonia.JAMA. 2020; ([Epub ahead of print])Crossref PubMed Scopus (607) Google Scholar,3Dong L. Tian J. He S. et al.Possible vertical transmission of SARS-CoV-2 from an infected mother to her newborn.JAMA. 2020; ([Epub ahead of print])Crossref PubMed Scopus (874) Google Scholar findings that may indicate vertical transmission of the virus in utero. In this study, PCR assays were performed to detect the presence of SARS-CoV-2 RNA in placental and membrane samples. Samples were obtained after delivery from a series women who received a diagnosis of COVID-19 during pregnancy. Institutional Review Board approval was obtained for this study. All pregnant patients who received a diagnosis of COVID-19 and who delivered between March 1, 2020, and April 20, 2020, at NYU Langone Health were included. Participants were identified by searching through the electronic medical record. Charts were reviewed for documentation of reverse transcription polymerase chain reaction (RT-PCR) testing of placental or membrane samples for SARS-CoV-2 RNA within 30 minutes after delivery. PCR testing for SARS-CoV-2 was performed using the Cepheid Xpert Xpress SARS-CoV-2 assay (Roche, Basel, Switzerland) under Emergency Use Authorization. Results obtained in this study were for "Research Use Only." Placental swabs were obtained from the amniotic surface after clearing the surface of maternal blood (PCR of placental sample). Membrane swabs were obtained from between the amnion and chorion after manual separation of the membranes (PCR of membrane sample). Maternal COVID-19 status was categorized as mild, severe, or critical.4Wu Z. McGoogan J.M. Characteristics of and important lessons from the coronavirus disease 2019 (COVID-19) outbreak in China: summary of a report of 72314 cases from the Chinese Center for Disease Control and Prevention.JAMA. 2020; ([Epub ahead of print])Crossref Scopus (12446) Google Scholar The time interval from maternal diagnosis of COVID-19 to delivery was calculated in days. Infants were tested for SARS-CoV-2 using PCR of nasopharyngeal swabs between day 1 of life and day 5 of life during hospitalization. Furthermore, the infants were assessed for clinical signs and symptoms of COVID-19, such as fever, cough, and nasal congestion. There were 32 pregnant patients with COVID-19 who delivered in this study, 11 of which had placental or membrane swabs performed (Table). Three of the 11 swabs returned positive for SARS-CoV-2. However, none of the infants tested positive for SARS-CoV2 on day 1 of life to day 5 of life, and none demonstrated symptoms of COVID-19.TableSummary of PCR results of placental or membrane samples from patients with COVID-19Patient no.Age, yGestational ageInterval from diagnosis of COVID-19 to delivery, dMode of deliveryPCR result of placental samplePCR result of membrane sampleCOVID-19 statusPCR results of infantsDOL1DOL2DOL3DOL4DOL513736wk 6d2CDN/APosCritical—Neg—Neg—23626wk 5d1CDN/APosCriticalNeg———Neg33838wk 3d0CDN/ANegCriticalNeg—Neg——44034wk 2d1CDPosN/ASevereNeg—NegNeg52637wk 6d0NSVDN/ANegSevereNeg—Neg——63437wk 1d10NSVDN/ANegMild——NegNeg—72341wk 3d1NSVDN/ANegMild—Neg———82340wk 5d8NSVDN/ANegMild—Neg———93539wk 6d15NSVDN/ANegMildNeg————103440wk 0d5NSVDN/ANegMildNeg————112241wk 0d15NSVDN/ANegMild—Neg———CD, cesarean delivery; COVID-19, coronavirus disease 2019; DOL, day of life; N/A, not available; Neg, negative; NSVD, normal spontaneous vaginal delivery; PCR, polymerase chain reaction; Pos, positive.Penfield. Detection of severe acute respiratory syndrome coronavirus 2 in placental and fetal membrane samples. AJOG MFM 2020. Open table in a new tab CD, cesarean delivery; COVID-19, coronavirus disease 2019; DOL, day of life; N/A, not available; Neg, negative; NSVD, normal spontaneous vaginal delivery; PCR, polymerase chain reaction; Pos, positive. Penfield. Detection of severe acute respiratory syndrome coronavirus 2 in placental and fetal membrane samples. AJOG MFM 2020. Of 11 placental or membrane swabs sent for testing after delivery, 3 swabs returned with positive results for SARS-CoV-2, all in women with severe to critical COVID-19 at time of delivery. This is the first study to find the presence of SARS-CoV-2 RNA in placental or membrane samples. Although there were no clinical signs of vertical transmission, the findings indicate the possibility of intrapartum viral exposure. Given the mixing of maternal and fetal fluid and tissues at the time of delivery, the origin of the detected SARS-CoV-2 RNA in this study is unclear. The source may be from maternal blood, amniotic fluid, or fetal membranes and amniotic sac. For those infants who were delivered vaginally, vaginal secretions is also a possible source; however, previous studies have not been able to demonstrate the presence of SARS-CoV-2 in vaginal secretions.5Qiu L. Liu X. Xiao M. et al.SARS-CoV-2 is not detectable in the vaginal fluid of women with severe COVID-19 infection.Clin Infect Dis. 2020; ([Epub ahead of print])Crossref Scopus (155) Google Scholar