Statistical analysis
Continuous variables were expressed as a median and interquartile range (IQR), whereas categorical variables were expressed as percentages. Mann-Whitney U and Fisher exact tests were applied for comparison of maternal demographic and clinical characteristics between COVID-19 patients with healthy controls. Data were analyzed using IBM SPSS Statistics for Windows, version 26.0 (Armonk, NY: IBM Corp.).
The alpha diversity, beta diversity, and vaginal microbiota composition of the COVID-19 group, and healthy control were compared. Alpha-diversity metrics were calculated as the number of phyla, genus, and species. The vaginal microbiota of asymptomatic or mild, moderate, or severe cases and healthy controls were compared. Beta-diversity was defined by using Bray-Curtis distance. The differences in alpha diversity metrics were performed by Wilcoxon signed-rank test using Python 3.7 (32-bit) and statistical significance was set as P value <.05. Statistical data were visualized with GraphPad Prism 8.0.2.
Data availability: All data generated or analyzed during this study are included in this published article.