Background: The association between age of menarche, age of menopause, reproductive lifespan and risk of stroke in Chinese women remains unclear and requires further clarification.<break><break>Methods: A stratified multi-stage random sampling method was used to select participants at baseline in 2012-2015. The participants? basic information was collected through a standardized questionnaire by professional investigator and examined by trained medical personnel. Follow-up was completed in 2019 to collect the stroke events. The Cox proportional hazards models were used to evaluate hazard ratios between reproductive factors and stroke risk. <break><break>Results: Overall, 11,256 women (5,155 non- menopausal women and 6,101 menopausal women) were included (mean [standard deviation] age, 55.2 [12.9] years). The risk was highest in women with menarche at age ≥17 years (HR, 1.290; 95%CI, 0.959~1.733) and with reproductive lifespan ≤28 years (HR, 1.643; 95%CI, 1.041~2.595). Age at menarche was positively associated with risk of stroke (HR, 1.086; 95%CI, 1.006~1.172). There was a negative association between age at menopause and stroke risk in women with 2 live births (HR, 0.897; 95%CI, 0.834~0.964). Reproductive lifespan was negatively associated with risk of stroke (HR, 0.963; 95%CI, 0.946~1.027). Subgroup analysis also showed that association between age at menarche, reproductive lifespan and stroke events.<break><break>Conclusions: Chinese women with late age at menarche and shorter reproductive lifespan have higher risk of stroke according to a large prospective study.

The authors have declared no competing interest.

The work was supported by the CAMS Innovation Fund for Medical Sciences [grant number 2017-I2M-1?004]; the China National Science & Technology Pillar Program [grant number 2011BAI11B01]; the surveillance of cardiovascular and its risk factors among Chinese Residents; he National Key R&D Pro- gram of China during the Thirteen Five-Year Plan Period [grant number No. 2018YFC1315303].

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The Ethics Committee of Fuwai Hospital (Beijing, China) approved the study.

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The datasets used and/or analyzed during the current study are available from the corresponding author Zengwu Wang (E-mail: wangzengwu@foxmail.com) on reasonable request.