Strengths and Limitations
The most important strength of the study is the first trial, which elucidated the relation of SARS-CoV-2 infection with the composition of vaginal flora. The vaginal samples were comprehensively collected from the healthy controls and women with COVID-19 disease. The samples from vaginal flora were analyzed exclusively by the three doctors in the group. Furthermore, we had longitudinal samples from three pregnant women, which provided an opportunity for comparison of vaginal composition of pregnant women before and after the disease. Further, detailed clinical data were collected from each participant and reported to consider for an evaluation of each subject.
There are several limitations. Our sample size was small to detect the statistical significance between women with severe COVID-19 and women with asymptomatic or mild disease, albeit with some significant differences. Secondly, a potential confounding factor that may differ among the groups was the use of antibiotics in the severe cases during the active stage at the time of sample collection.