Difference in Precocious Puberty Between Pre-COVID-19 and COVID-19 Periods: A Meta-Analysis

Abstract We conducted this systematic review and meta-analysis to clarify the trend of precocious puberty (PP) incidence after the COVID-19 outbreak and explore potential contributing factors, such as age at presentation and body mass index standard deviation score (BMI SDS). Children visiting pediatric endocrinology clinics for the first time for suspected PP were included. We searched databases until February 28, 2023 for studies reporting various indicators of PP incidence before and during the pandemic. Total numbers of events and observations were recorded. A meta-analysis was performed to compare the odds of PP, BMI SDS, and age at presentation between the two periods. The dose–response relationships between time points (by number of years away from the pandemic) and PP risk were explored. In summary, a total of 32 studies including 24,200 participants were recruited. COVID-19 pandemic was associated with the increasing odds of PP among children referred for suspicious condition (OR 1.96; 95% CI 1.56–2.47; I2 = 54%; P < 0.001). Sensitivity analysis confirmed the robustness of the findings. BMI SDS did not vary between the two periods, while age at presentation was lower following the pandemic. PP incidence increased more rapidly during the pandemic period than during the prepandemic period.