title: Reduced risk of prostate cancer in childless men as compared to fathers: a systematic review and meta-analysis.
abstract: The previously reported association between fatherhood status and prostate cancer risk was controversial. We carried out the present meta-analysis of all relevant studies to summarize evidence on this association. A comprehensive literature search of studies was performed in PubMed, Web of Science, and the Chinese National Knowledge Infrastructure (CNKI) databases, covering all the papers published from their inception to September 2015. The combined risk estimates with 95% confidence intervals (CIs) were calculated using a random effects model. Heterogeneity and publication bias were also evaluated. A total of 11 studies were finally included in this meta-analysis. We found a significantly reduced risk of prostate cancer associated with being childless (OR 0.91, 95% CI 0.87-0.96). There was statistically significant heterogeneity across the studies (P < 0.001, I(2) = 88.2%). In summary, this meta-analysis supports that being fatherless is associated with a lower risk of prostate cancer. Because of the substantial heterogeneity and residual confounding, using other study designs to further explore this association and the underling mechanism is warranted.
authors.affiliation: Department of Urology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310003, China.
authors.forename: Yeqing
authors.initials: Y
authors.lastname: Mao
authors.affiliation: Department of Urology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310003, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Xu
authors.affiliation: Department of Urology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310003, China.
authors.forename: Xiangyi
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Department of Urology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310003, China.
authors.forename: Liping
authors.initials: L
authors.lastname: Xie
mesh_terms: D005220:Fathers; D006801:Humans; D008297:Male; D016017:Odds Ratio; D011471:Prostatic Neoplasms / Q000453:epidemiology* / Q000209:etiology*; D017594:Publication Bias; D043762:Reproductive Behavior; D012306:Risk