Objective: Season of birth influences the rate of several psychiatric disorders. In this study, we investigated whether climacteric symptoms and, in particular, psychological and somatic symptoms of postmenopausal women were influenced by their season of birth.
Design: This retrospective multicenter study was performed on 2,541 women in natural menopause, free of hormone therapy. The score of the Greene Climacteric Scale and of its vasomotor, psychological (anxiety and depression), and somatization subscales were stratified by season of a woman's birth. Data were controlled for possible confounders, such as age, years since menopause, body mass index, education occupation, smoking habits, and season of evaluation.
Results: The Greene Climacteric Scale appeared to be associated with the season of birth, with the lowest scores being observed in women born in autumn and the highest scores in women born in spring (+2.11; 95% CI, 0.67-3.56; P = 0.01), and summer (+2.22; CI, 0.82-3.63; P = 0.01). Lowest scores in autumn and highest scores in spring were also observed for psychological symptoms subscaled as anxiety and depression (+1.43; CI, 0.54-2.32; P = 0.01) and somatic symptoms (+0.59; CI, 0.15-1.04; P = 0.01).
Conclusions: In this study, we found a relationship between season of birth and some menopause-associated symptoms. Further study is needed to confirm these relationships and examine possible mechanisms.