Characteristics of the included studies
The main characteristics of the included studies are presented in Table 1. The publication years ranged from 2010 to 2021, with the first members of the offspring cohort delivered in 1997. The sample sizes of the included studies ranged from 476 to 698,056, and 10,010 pregnant mothers were exposed to neuraminidase inhibitors during pregnancy; only one study examined an Eastern population. Overall, two were hospital-based cohort studies. Based on the methodological quality assessment scores, most studies were deemed to be of high quality; only one was categorized as low quality. The score breakdown is shown in Table S2.