New York. We also sought to determine if there are differences between sites that 20 reflect the demographic variations in the local populations served by each hospital. 21
This retrospective cohort study evaluated all women admitted for delivery at four 24 hospitals within Northwell Health, the largest academic health system in New York, from 25 women were previously tested and diagnosed with COVID-19 secondary to symptoms. 52
Thus, the overall prevalence of positive SARS-CoV-2 RT-PCR testing was 18.6%
Among the 64 women who were positive for the virus on universal testing, 70.3% were 56 asymptomatic and this did not differ significantly across the four hospitals (Figure 1) . 57
Three patients with negative testing reported symptoms and, in each case, an alternate 58 diagnosis was strongly suspected (e.g. fever associated with intra-amniotic infection). 59
Among symptomatic patients diagnosed with COVID-19 at the time of universal testing 60 (n=19/64), cough was most common (57.9%), followed by fever (52.6%) and dyspnea 61 (47.4%). 62
Considerable heterogeneity was observed across sites (Table 1) Data are provided as mean (±SD), n (percentage), or median (interquartile range). a race-ethnicity data available for 96.9% of patients (n=370). b COVID-19 PCR testing occurred more than 48 hours before admission secondary to symptoms.