It has been reported that the estrogen receptor alpha (ESR1) rs9340799 polymorphism is associated with age at menarche (AAM). However, recent investigations have generated inconsistent results. This study aimed to establish a more precise estimation of the association between this polymorphism and AAM. A meta-analysis was conducted based on an in silico literature search using PubMed. Six studies presenting continuous data, including ESR1 rs9340799 genotype frequencies, were selected.