[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]. / La preparedness dell'Italian obstetric surveillance system in occasione della pandemia da SARS-CoV-2: aspetti metodologici di uno studio di popolazione.

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.

A large series of molecular and serological specimens to evaluate mother-to-child SARS-CoV-2 transmission: a prospective study from the Italian Obstetric Surveillance System.

OBJECTIVES: To assay the presence of the SARS-CoV-2 genome in vaginal, rectal, and placental swabs among pregnant women and in newborn nasopharyngeal swabs and to investigate the immunological response and maternal antibody transfer through the umbilical cord blood and milk of unvaccinated mothers. METHODS: Vaginal, rectal, and placental specimens, maternal and neonatal serum, and milk were collected from a wide cohort of pregnant Italian women with confirmed SARS-CoV-2 infection admitted to the hospital between February 25, 2020 and June 30, 2021. Samples were tested in selected reference laboratories according to a shared interlaboratory protocol. RESULTS: Among 1086 enrolled women, the SARS-CoV-2 positive rate detected in all specimens ranged from 0.7% to 8.4%. Respectively, 45.2% of maternal sera collected during pregnancy and 39.7% of those collected at birth tested positive for immunoglobulin G, whereas 50.5% tested positive among neonates. Nasopharyngeal swabs were positive in 0.8% of the newborns, and immunoglobulin G was detected in 3.0% of the milk samples. The highest immunological response was recorded within 30 days during pregnancy and within 60 days of birth and in the neonatal population. CONCLUSION: Vertical transmission should be considered a rare event; although, a good maternal immunological response and antibodies transfer throughout the umbilical cord blood was detected.

Vaccination against SARS-CoV-2 in pregnancy during the Omicron wave: the prospective cohort study of the Italian obstetric surveillance system.

OBJECTIVES: Evidence on the effects of the SARS-CoV-2 Omicron variant on vaccinated and unvaccinated pregnant women is sparse. This study aimed to compare maternal and perinatal outcomes of women infected with SARS-CoV-2 during the Omicron wave in Italy, according to their vaccine protection. METHODS: This national prospective cohort study enrolled pregnant women with a positive SARS-CoV-2 nasopharyngeal swab within 7 days of hospital admission between 1 January and 31 May, 2022. Women who received at least one dose of vaccine during pregnancy and those who completed the vaccine cycle with the first booster were considered protected against moderate or severe COVID-19 (MSCD). A multivariable logistic regression model evaluated the association between vaccine protection and disease severity. Maternal age, educational level, citizenship, area of birth, previous comorbidities, and obesity were analysed as potential risk factors. RESULTS: MSCD was rare (41/2147, 1.9%; 95% CI, 1.4-2.6), and the odds of developing it were significantly higher among unprotected women (OR, 2.78; 95% CI, 1.39-5.57). Compared with protected women (n = 1069), the unprotected (n = 1078) were more often younger, with lower educational degrees, and foreigners. A higher probability of MSCD was found among women with previous comorbidities (OR, 2.86; 95% CI, 1.34-6.12) and those born in Asian countries (OR, 3.05; 95% CI, 1.23-7.56). The percentage of preterm birth was higher among women with MSCD compared with milder cases (32.0% [8/25] versus 8.4% [161/1917], p < 0.001) as well as the percentage of caesarean section (52.0% [13/25] versus 31.6% [606/1919], p 0.029). DISCUSSION: Although severe maternal and perinatal outcomes were rare, their prevalence was significantly higher among women without vaccine protection. Vaccination during pregnancy has the potential to protect both the mother and the baby, and it is therefore strongly recommended.

Placental Characteristics of a Large Italian Cohort of SARS-CoV-2-Positive Pregnant Women.

The variety of placental morphological findings with SARS-CoV-2 maternal infections has raised the issue of poor agreement in histopathological evaluation. The aims of this study were: to describe the histopathological placental features of a large sample of SARS-CoV-2-positive women who gave birth in Italy during the COVID-19 pandemic, to analyse the factors underlying these lesions, and to analyse the impact of placental impairment on perinatal outcomes. From 25 February 2020 to 30 June 2021, experienced perinatal pathologists examined 975 placentas of SARS-CoV-2-positive mothers enrolled in a national prospective study, adopting the Amsterdam Consensus Statement protocol. The main results included the absence of specific pathological findings for SARS-CoV-2 infections, even though a high proportion of placentas showed signs of inflammation, possibly related to a cytokine storm induced by the virus, without significant perinatal consequences. Further research is needed to better define the clinical implications of placental morphology in SARS-CoV-2 infections, but the results of this large cohort suggest that placentas do not seem to be a preferential target for the new Coronavirus infection.

The first SARS-CoV-2 wave among pregnant women in Italy: results from a prospective population-based study

Introduction. This study aimed to estimate the incidence of SARS-CoV-2 infection among pregnant women during the first pandemic wave in Italy, and to describe COVID-19 disease characteristics and maternal and perinatal outcomes. Materials and methods. National population-based prospective cohort study collecting information on women with SARS-CoV-2 diagnosis, confirmed within 7 days from hospital admission. Results. The national SARS-CoV-2 rate was 6.04 per 1,000 births (95% CI 5.62-6.49) among pregnant women and 7.54 (95% CI 7.47-7.61) among women in reproductive age. 72.1% of the cohort developed mild COVID-19 disease without pneumonia nor need for ventilatory support. Severe disease was significantly associated with women’s previous comorbidities (OR 2.55;95% CI 0.98-6.90), obesity (OR 4.76;95% CI 1.79-12.66) and citizenship from High Migration Pressure Countries (OR 3.43;95% CI 1.27-9.25). Conclusions. During the first pandemic wave in Italy, the SARS-CoV-2 rate among pregnant women was lower compared to that detected among women of reproductive age, and risks of severe COVID-19 disease and adverse maternal and perinatal outcomes were rare.

Coronavirus and birth in Italy: results of a national population-based cohort study.

INTRODUCTION: The study was implemented to provide guidance to decision-makers and clinicians by describing hospital care offered to women who gave birth with confirmed SARS-CoV-2 infection. MATERIALS AND METHODS: National population-based prospective cohort study involving all women with confirmed SARS-CoV-2 infection who gave birth between February 25 and April 22, 2020 in any Italian hospital. RESULTS: The incidence rate of confirmed SARS-CoV-2 infection in women who gave birth was 2.1 per 1000 maternities at a national level and 6.9/1000 in the Lombardy Region. Overall one third of the women developed a pneumonia and 49.7% assumed at least one drug against SARS-CoV-2 infection. Caesarean rate was 32.9%, no mothers nor newborns died. Six percent of the infants tested positive for SARS-CoV-2 at birth. CONCLUSIONS: Clinical features and outcomes of COVID-19 in women who gave birth are similar to those described for the general population, most women developing mild to moderate illness.