Increasing number of G alleles at rs9282861, which would be expected to result in increased SULT1A1 activity, was associated with earlier age at menopause (ranging from an average age of 50.15 y among women with 0 G alleles to 45.29 y among those with 4 G alleles; P = 0.014), decreased frequency of night sweats (P = 0.009), and less severe insomnia (P = 0.046) (Fig. 2 and Table 2). This evidence concerns the gene SULT1A1 and insomnia measurement.