Adaptation of the Sars-Cov-2 Screening and Testing Strategy in Pregnant Women during the Second Wave of the Covid-19 Pandemic

Background: Approaches to SARS-CoV-2 screening and testing of pregnant women vary among different obstetrics units and are usually tailored to the current epidemiological situation. Dramatic increase in the SARS-CoV-2 incidence in autumn 2020 prompted our hospital to adapt its protocol for SARS-CoV-2 screening and testing of pregnant women at admission. Methods: To assess the usefulness of the updated SARS-CoV-2 screen-and-test approach, we retrospectively reviewed the Ljubljana Maternity Hospital database and searched for pregnant women admitted to the hospital between 27 October 2020 and 28 February 2021. SARS-CoV-2 real-time reverse-transcription polymerase chain reaction (RT-PCR) and Rapid Antigen Test (RAT) results were retrieved from the database. Results: During the four-month period analysed, 2,552 hospitalizations and 5,516 outpatient visits occurred at our hospital. Records for nasopharyngeal swab testing using SARS-CoV-2 RAT were available for 1,836 questionnaire screen-negative women admitted for delivery, planned procedure or hospitalization, of which 26 (1.4%) tested RAT positive. Subsequent RT-PCR testing identified presence of SARS-CoV-2 RNA in 20/26 (76.9%) and RAT false-positive results in 6/26 (23.1%) cases. Conclusions: During the peak of the COVID-19 pandemic in Slovenia, the updated screen-and-test approach using RAT with subsequent RT-PCR confirmation identified 1.1% of screen-negative pregnant women to be infected with SARS-CoV-2 at admission. Our experience may help efficient adaptation of screen-and-test approaches in obstetric units facing a surge in SARS-CoV-2 cases.