The incidence of precocious puberty (PP) in Chinese children is increasing year by year, precocious children are more likely to have physical and mental health problems than normal children, and their growth can be affected. In view of the current clinical lack of understanding and prevention measures for PP, it's of great significance to clarify the relevant influencing factors and provide references for the prevention and treatment of PP.

To systematically evaluate the factors associated with PP in Chinese children.

We searched PubMed, Web of Science, Embase, Cochrane Library, CBM, CNKI, VIP and Wanfang databases, the search period was from the establishment of the database to April 30, 2024. Two researchers independently screened the literature, extracted data and assessed the quality of the included literature, and we performed Meta-analysis using Stata 15.0 software.

A total of 41 studies covering 44 221 cases were selected, and 31 influencing factors were extracted. Methodological quality evaluation of the literature shows that 20 medium-quality and 21 high-quality studies were included. Meta-analysis demonstrated that: female (OR=1.64) , urban settlement (OR=4.13) , residential near chemical industry park (OR=2.52) , maternal age at menarche≤12 years old (OR=2.37) , >12-14 years old (OR=3.04) , low parental education (OR=2.41) , poor parental relationship (OR=4.37) , parental companionship <0.5 years (OR=2.05) , screen time (OR=3.07) , love romantic films and novels (OR=5.94) , outdoor activity<1 h/d (OR=3.86) , sleep with the light on (OR=2.48) , use of adult chemical products (OR=5.36) , plastic products are often used at home (OR=2.45) , heavy school workload (OR=2.63) , family history of PP (OR=3.23) , high BMI (OR=1.57) , sleep duration (OR=2.57) , frequent consumption of nutritional supplements (OR=3.01) , high-calorie and high-fat diets (OR=3.05) , high protein diets (OR=2.47) , animal food (OR=3.35) , sweets (OR=5.85) , food containing pigments or preservatives (OR=1.80) , leptin (OR=5.34) , estradiol (OR=3.32) , luteinizing hormone (OR=3.71) , insulin-like growth factor 1 (OR=2.70) and follicle stimulating hormone (OR=2.40) levels were the main risk factors for PP in Chinese children (P<0.05) , whereas maternal age at menarche >14 years (OR=0.64) , outdoor activity ≥2 h/d (OR=0.73) and consumption of vegetables and fruits ≥200 g/d (OR=0.60) were protective factors (P<0.05) .

Our findings show that the occurrence of PP in Chinese children is influenced by a multitude of sociodemographic, psychosocial, genetic, physiological, dietary, and environmental factors, among which the later age of mother´s menarche, the longer outdoor activities and the consumption of vegetables and fruits ≥200 g/d are protective factors. In the future, it is necessary to investigate and intervene on controllable factors. Families, schools and hospitals can work together to avoid or reduce the occurrence of PP in children.