RT Journal Article SR Electronic T1 Paternal smoking and spontaneous abortion: a population-based retrospective cohort study among non-smoking women aged 20–49 years in rural China JF Journal of Epidemiology and Community Health JO J Epidemiol Community Health FD BMJ Publishing Group Ltd SP 783 OP 789 DO 10.1136/jech-2017-210311 VO 72 IS 9 A1 Long Wang A1 Ying Yang A1 Fangchao Liu A1 Aimin Yang A1 Qin Xu A1 Qiaomei Wang A1 Haiping Shen A1 Yiping Zhang A1 Donghai Yan A1 Zuoqi Peng A1 Yuan He A1 Yuanyuan Wang A1 Jihong Xu A1 Jun Zhao A1 Hongguang Zhang A1 Ya Zhang A1 Qiaoyun Dai A1 Xu Ma YR 2018 UL http://jech.bmj.com/content/72/9/783.abstract AB Background To comprehensively evaluate the association of paternal smoking and spontaneous abortion.Methods We conducted a population-based retrospective cohort study among 5 770 691 non-smoking rural Chinese women, along with their husbands, participating in the National Free Pre-Pregnancy Checkups Project, regarding outcome events that occurred in 2010–2016. The main outcome was spontaneous abortion (SA). Multivariable logistic regression was used to estimate OR and 95% CI, and restricted cubic spline was used to estimate the non-linear relationship.Results The multivariable-adjusted OR of exposure to paternal smoking for SA was 1.17 (95% CI 1.16 to 1.19), compared with women without exposure to paternal smoking; and corresponding OR of exposure to preconception paternal smoking for SA was 1.11 (95% CI 1.08 to 1.14), compared with women without exposure to preconception paternal smoking. The ORs of preconception paternal smoking also increased with increases in paternal smoking (pnonlinear<0.05, almost linearly shaped) and preconception paternal smoking (pnonlinear>0.05). In addition, periconception paternal smoking cessation was associated with an 18% (15%–22%) lower risk of SA.Conclusion Paternal smoking was associated with SA. The importance of tobacco control, specifically pertaining to paternal smoking, should be emphasised during preconception and pregnancy counselling.