[The preparedness of the Italian obstetric surveillance system in the response to the emergency of the SARS-CoV-2 pandemic: methodological aspects of a population-based study].

This paper aims to describe the Italian obstetric surveillance system (ItOSS) preparedness as an element for a timely response to the new Coronavirus pandemic. ItOSS is a surveillance network that has been collecting data on maternal mortality and conducting population studies on obstetric near misses since 2013. At the beginning of the pandemic, ItOSS launched a new population-based project to monitor SARS-CoV-2 infection during pregnancy and post-partum and promptly give back information useful to clinicians and decision-makers. All the regions and autonomous provinces, for a total of 289 birth units (PN), joined the study. Data relating to pregnant or post-partum women with a confirmed SARS-CoV-2 infection diagnosis addressing the maternities for outpatient visits or hospitalization were collected. The project methodology entails that each participating maternity reports the cases to ItOSS uploading data through an open-source platform. The on-line form includes sociodemographic and clinical data and maternal-neonatal outcomes. Biological samples to detect possible vertical transmission are also collected voluntarily. A total of 534 incident cases were reported from February 25th to July 10th 2020; 7 regions also collected biological samples for 227 cases; data collection is still ongoing.A preliminary analysis of the first 146 SARS-CoV-2 positive women who gave birth between February 25th to April 22nd shows an incidence rate of the infection equal to 2.1/1,000 in Italy and 6.9/1,000 in the Lombardy Region (Northern Italy). The brief time needed to setting up and operating the project, the national coverage, the adoption of shared tools for data collection, the quality and completeness of the information collected show how the availability of active networks like ItOSS represents a crucial element to hold a high level of preparedness in case of a health emergency.