Elevated sFlt-1/PlGF was observed in most early-onset FGR pregnancies from 4 weeks before delivery, and values were even higher if there was concurrent PE. However, serial measurements of the ratio were of limited value, being useful only to anticipate the need for imminent delivery in cases of FGR with PE when sFlt-1/PlGF values ≥ 655 were reached. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

What are the novel findings of this work? In pregnancies with early-onset fetal growth restriction and antegrade umbilical artery flow, soluble fms-like tyrosine kinase-1/placental growth factor (sFlt-1/PlGF) ratio at diagnosis is associated with the time interval to delivery. What are the clinical implications of this work? Determination of sFlt-1/PlGF ratio in pregnancies with early-onset fetal growth restriction and antegrade umbilical artery flow may be helpful in planning surveillance, corticosteroid administration and outpatient vs inpatient management.

Objectives To evaluate the progression of the seroprevalence of SARS-CoV-2 in the pregnant population of the south of Madrid during the first wave of the COVID-19 pandemic. Secondarily we aimed to evaluate maternal and perinatal outcomes. Study design Retrospective cohort study conducted at Hospital Universitario 12 de Octubre during weeks 10 to 19 of 2020, coinciding with the Spanish lockdown. We tested 769 serum samples obtained from routine serological testing during the first and third trimesters of pregnancy for specific IgG anti SARS-CoV-2 RBD and S proteins. RT-PCR tests were performed in suspected cases according to clinical practice. We compared maternal and perinatal outcomes in those with delivered pregnancies (n = 578) according to the presence or absence of specific IgG antibodies. Those with positive IgG were subdivided by the presence or absence of Covid-19 related symptoms at any time and the results of RT-PCR testing if performed. Therefore, we had 4 study groups: G1 (IgG negative), G2 (IgG positive, asymptomatic, RT-PCR testing negative or not done), G3 (IgG positive, symptomatic, RT-PCR testing negative or not done), and G4 (IgG positive, symptomatic, RT-PCR positive). Results Seropositivity increased from 0% to 21.4% (95% CI 11.8–31.0) during the study period, of which 27.9% had an asymptomatic course. Overall outcomes were favorable with a significant increased rate of preterm birth in G4 vs G1 (21.4% vs 6.7%) and cesarean/operative delivery (50% vs 26.9%). Asymptomatic and mild cases did not have differences regarding pregnancy course when compared to seronegative women. There were no documented cases of vertical or horizontal transmission. Conclusion Seroprevalence in pregnant women in southern Madrid went up to 21.4% of which 27.9% had an asymptomatic course. Overall perinatal results were favorable, especially in those asymptomatic.