Background: Menarche age has been associated inconsistently with the occurrence, timing or severity of major depressive disorder (MDD), but rarely studied in women with bipolar (BDs) or anxiety disorders. Methods: We investigated women patients at a Sardinian mood disorder center for associations of age at menarche with age at illness onset for major affective or anxiety disorders, year of birth, and other selected factors, using bivariate comparisons and multivariate regression modeling. Results: Among women (n = 1139) with DSM-IV MDD (n = 557), BD-I (n = 223), BD-II (n = 178), or anxiety disorders (n = 181), born in 1904-1998, of mean age 42.9 years, menarche age averaged 12.8 [CI: 12.7-12.9] years. Illness onset age averaged 30.9 [30.1-31.8] years, ranking: BD-I, 25.8; anxiety disorders, 28.0; BD-II, 30.3; MDD, 34.1 years. Menarche age declined secularly over birth years, and was associated with younger illness-onset, having no or fewer siblings, more psychiatrically ill first-degree relatives, living in rural environments, being suicidal, substance abuse, and being unemployed. Earlier menarche and earlier illness-onset were significantly associated for onset age groups of40 years. Menarche age versus diagnosis ranked: BD-II < BD-I < anxiety disorders < MOD. Conclusions: Age at menarche in Sardinia, as elsewhere, has declined over the past decades. It was strongly associated with age at onset of bipolar and anxiety, as well as major depressive disorders across the age range, suggesting sustained effects of biological maturational factors. (C) 2016 Elsevier Masson SAS. All rights reserved.