Reproductive history and gastric cancer among post-menopausal women.

A total of 339 post-menopausal women with gastric cancer (GC) and 515 population controls were interviewed in a multicenter study in Italy for information on reproductive history, dietary habits and other socio-demographic variables. After adjusting for these factors, GC risk was significantly higher among women reporting menopause below age 45, while no effect was shown for age at menarche, parity, age at first livebirth, and number of abortions. When age at menopause was considered together with age at menarche for an index of fertility years, GC risk showed a significant inverse relation to duration of fertility. These results suggest a protective role for endocrine or other factors related to late age at menopause or to length of fertility. These findings may be relevant to explain the fact that rates of GC reported among females are lower than among males around the world, and suggest the need for further research into hormonal and other related risk factors.