Analysis of the transplacental transmission of SARS CoV-2 virus and antibody transfer according to the gestational age at maternal infection

• Published in: Scientific reports Vol. 14; no. 1; p. 3458
• Main Authors: Lucot-Royer, Louise, Nallet, Camille, Vouga, Manon, Puyraveau, Marc, Mauny, Frederic, Marty-Quinternet, Solène, Bertholdt, Charline, Bory, Jean-Paul, Devalland, Christine, Canaguier, Margaux, Copolla, Camille, Eszto, Marie-Laure, Montoya, Yohny, Roesch, Marion, Reviron, Sandrine, Riethmuller, Didier, Rufenacht, Emma, Simon, Emmanuel, Mottet, Nicolas
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 11.02.2024; Nature Publishing Group; Nature Portfolio
• Subjects: 631/250/254; 631/250/255/2514; 692/308/174; 692/308/409; 692/700/3160; Age; Antibodies; Antibodies, Viral; Birth; Congenital infection; COVID-19; Enzyme-linked immunosorbent assay; Female; Fetuses; Gestational Age; Humanities and Social Sciences; Humans; Immunoglobulin G; Immunoglobulin M; Infant, Newborn; Infections; Mothers; multidisciplinary; Neonates; Placenta; Polymerase chain reaction; Pregnancy; Pregnancy Complications, Infectious; SARS-CoV-2; Science; Science (multidisciplinary); Serology; Severe acute respiratory syndrome coronavirus 2; Spike Glycoprotein, Coronavirus; Spike protein
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-024-53580-5

To quantify transplacental transmission of SARS-CoV-2 virus and antibody transfer in pregnant women and their newborns according to the gestational age at maternal infection. A prospective observational multicenter study including pregnant women with a positive RT-PCR or a positive serology for SARS-CoV-2 and compatible symptoms, from April to December 2020, in 11 French maternities. The study was designed to obtain a systematic collection of mother-infant dyad’s samples at birth. SARS-CoV-2 viral load was measured by RT-PCR. IgG and IgM antibodies against the SARS-CoV-2 spike protein were measured by enzyme-linked immunosorbent assay. Antibody concentrations and transplacental transfer ratios were analyzed according to the gestational age at maternal infection. The primary outcome was the rate of SARS CoV-2 materno-fetal transmission at birth. The secondary outcome was the quantification of materno-fetal antibody transfer. Maternal and neonatal outcomes at birth were additionally assessed. Among 165 dyads enrolled, one congenital infection was confirmed {n = 1 (0.63%) IC 95% [0.02%; 3.48%]}. The average placental IgG antibody transfer ratio was 1.27 (IC 95% [0.69–2.89]). The transfer ratio increased with increasing time between the onset of maternal infection and delivery ( P Value = 0.0001). Maternal and neonatal outcomes were reassuring. We confirmed the very low rate of SARS-CoV-2 transplacental transmission (< 1%). Maternal antibody transfer to the fetus was more efficient when the infection occurred during the first and second trimester of pregnancy.