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Flowchart of study patients. aMost patients missing SARS‐CoV‐2 PCR results delivered before mid‐April 2020 (n = 1238; 97%). bResolved prenatal infection was not evaluated after December 2020 because widespread availability of SARS‐CoV‐2 vaccination renders positive antibody results uninterpretable. PCR, polymerase chain reaction; SARS‐CoV‐2, severe acute respiratory syndrome coronavirus 2
