BACKGROUND: COVID-19 transmission from mother to infant suggests that vertical and horizontal transmission of COVID-19 are possible. Here we describe the demographic and clinical characteristics and outcomes of SARS-CoV-2 positive pregnant women and their newborns. Summarized Characteristics of 19 COVID-19 Positive Mothers that Delivered 3/31/20–6/17/20 at Boston Medical Center [Image: see text] METHODS: We collected data from the electronic medical records of pregnant women. Data composed of maternal demographics and morbidities, and symptoms of COVID-19. Descriptive statistics were used to analyze data. Women had positive polymerase chain reaction (PCR) testing done by nasopharyngeal swabs. Each newborn was tested for SARS_CoV-2 by RT_PCR with a nasopharyngeal swab at 24 hours, 48 hours, and day 5 of life. RESULTS: 36 women met criteria to be included in this study. 22% had chronic hypertension, 8% had asthma, one had chronic HIV and hepatitis C, 30% had pregnancy-related morbidities including pregnancy-induced hypertension (19%), cholestasis of pregnancy (8%) and gestational diabetes(3%) (Table1) Of the 32 deliveries to date, 17 (53% delivered vaginally and 15 (47%) via C-section. Of the 15 C-sections, 6 (40%) were due to complications related to COVID-19. 38% (14/36) women developed hypoxia. Five newborns (15%) born to SARS-CoV-2 positive mothers had positive PCR testing for SARS-CoV-2. 2 of them were born prematurely and by C section secondary to COVID 19 infection respiratory deterioration. One premature infant tested positive for RT-PCR for SARS-CoV-2 on days 1, 2, and 5. The other one was positive on day 2. The two full-term newborns who tested positive by PCR for COVID 19 after delivery, were not delivered secondary to COVID 19 complications. One infant who was separated from his mother was negative by PCR at days 1,2 and 5 but tested positive later after being in contact with his mother. CONCLUSION: Our population of pregnant mothers had a high incidence of cesarean section secondary to COVID 19 infection complications. They also had a high frequency of chronic health conditions. Infants born to mothers with COVID-19 can have positive PCR tests for SARS-CoV-2 suggesting that both, vertical and horizontal mother to infant transmission is possible. Infants had negative tests before positive tests, suggesting false negative testing may have occurred. DISCLOSURES: All Authors: No reported disclosures
524. COVID 19 Infection in Pregnant Women and Newborn Infants at a Single U.S. Center: What Disparities, Testing and Isolation Practices can Teach Us