Study limitation.
The asymptomatic prevalence study was implemented nine weeks after the first confirmed case of SARS-CoV-2 infection was reported in Ireland (March 1st 2020) and 16 days after the peak of the population infection (33). Our study commenced as the rate of new cases of infection was already falling and therefore may account, in part, for the low prevalence of PCR positive cases in this cohort. However, the low antibody prevalence in our study correlates with other large population-based studies and suggests that even at this stage of the pandemic, the vast majority of the pregnant population remains immunologically naïve.
Five seropositive patients delivered during this study period. Further analysis of the transplacental passage of antibodies in umbilical cord blood from additional women, will provide further credence to our findings and is required to assist in counselling pregnant women and directing future vaccination strategies.