3.1. Study Population
diarrhea, allergies
ALLERGIES
A total of 247 infants aged 6–24 months and delivered by C-section were recruited into the study. After the initial screening, 128 infants who did not meet the inclusion criteria were excluded, and the parents or guardians of another 10 refused to participate. Finally, the parents or guardians of 109 infants signed the informed consent form and were officially included in the study. During the follow-up, five participants in the test group withdrew from the study due to the COVID-2019 epidemic, allergies, time conflicts, etc. Three participants in the control group withdrew due to the impact of the epidemic and diarrhea, with an overall dropout rate of 7.3%. Most of the subjects withdrew within 4 weeks, and data filling was limited, so the principle of following the research protocol was adopted for analysis. 