عنوان مقاله [English]
Introduction: Colon cancer is one of the cancers which are strongly influenced by environmental factors. In 1980, "feminine sex hormones" were suggested as factors that might be related with colon cancer and many studies have been performed since then. The present case-control study investigated the correlation of menstrual, reproductive and oral contraceptive (OCP) factors with colon cancer in women older than 45 years old who had colon cancer.
Methods: This case-control study was conducted in two major hospitals of Mashhad. It enrolled 83 women with colon cancer in the study group and 99 women who were admitted to Ghaem and Imam Reza hospitals for the conditions unrelated to gastrointestinal and gynecological diseases in the control group. The median age of the participants was at least 45 years old.
Factors such as parity, age at first full-term pregnancy, number of abortions, age at menopause and duration of OCP usage (in years) were compared between the two groups.
Results: There was a significant trend of decreasing colon cancer risk with increased parity (p=0.01). Age at first pregnancy was directly associated with the risk of development of colon cancer (p<0.01). There was no significant difference in number of abortions between those two groups of our study. (p>0.1) Also there was no significant correlation of the age at menopause of older than 50 years and OCP usage with the risk of development of colon cancer (p>0.1, p>0.1, respectively).
Conclusion: Based on the findings of the present study, it seems that the relationship between reproductive factors and colon cancer is more prominent than menstrual factors and OCP usage, but verification or rejection of this conclusion needs stronger and more consistent evidences.