Risk of CRC was increased for women undergoing hysterectomy or oophorectomy.

Given that 300,000 women without susceptibility genes for ovarian cancer or metrocarcinoma undergo oophorectomy or hysterectomy every year, the association of oophorectomy or hysterectomy with increased morbidity of CRC in the entire population has implications for public health guidance.

Lacking randomized controlled trials, these high-quality cohort studies with large size and high follow-up rate of long-term follow-up offer a good method to assess these associations.

This meta-analysis is the first to evaluate these controversial results.