Impact of SARS-CoV-2 Positivity on Delivery Outcomes for Pregnant Women between 2020 and 2021: A Single-Center Population-Based Analysis

Abstract

Despite the existing body of evidence, there is still limited knowledge about the impact of SARS-CoV-2 positivity on delivery outcomes. We aimed to assess the impact of SARS-CoV-2 infection in women who gave birth at the University Hospital "Federico II" of Naples, Italy, between 2020 and 2021. We conducted a retrospective single-center population-based observational study to assess the differences in the caesarean section and preterm labor rates and the length of stay between women who tested positive for SARS-CoV-2 and those who tested negative at the time of labor. We further stratified the analyses considering the time period, dividing them into three-month intervals, and changes in SARS-CoV-2 as the most prevalent variant. The study included 5236 women with 353 positive cases. After vaccination availability, only 4% had undergone a complete vaccination cycle. The Obstetric Comorbidity Index was higher than 0 in 41% of the sample. When compared with negative women, positive ones had 80% increased odds of caesarean section, and it was confirmed by adjusting for the SARS-CoV-2 variant. No significant differences were found in preterm birth risks. The length of stay was 11% higher in positive cases but was not significant after adjusting for the SARS-CoV-2 variant. When considering only positive women in the seventh study period (July-September 2021), they had a 61% decrease in the odds of receiving a caesarean section compared to the fourth (October-December 2020). Guidelines should be implemented to improve the safety and efficiency of the delivery process, considering the transition of SARS-CoV-2 from pandemic to endemic. Furthermore, these guidelines should aim to improve the management of airborne infections in pregnant women.

Keywords: COVID-19; SARS-CoV-2; birth; delivery; pregnancy; vaccination.

Figure 1

Association between SARS-CoV-2 positivity and the risk of preterm birth, caesarean section deliveries, and percentage increase in the hospital length of stay for delivery. Notes: (A) The binary outcomes were modeled using multivariable logistic regression models, controlled for age at the time of delivery, caesarean section (if not the outcome), and the Obstetric Comorbidity Index. For the main analyses, the models were further adjusted for three-month study periods, whilst the sensitivity analyses for time were divided according to changes in the most prevalent SARS-CoV-2 variant, rather than the three-month study period. The analyses were presented as odds ratios (ORs) and 95% confidence intervals (95% CI). C-section: caesarean section. (B) The outcomes were modeled by employing multivariable Poisson regression models, controlled for age at the time of delivery, caesarean section, and Obstetric Comorbidity Index. For the main analyses, the models were further adjusted for three-month study periods, while in the sensitivity analyses, time was divided according to changes in the most prevalent SARS-CoV-2 variant, rather than three-month study periods. The analyses were presented as incidence rates (IRRs) and 95% confidence intervals (95% CI).