Study population
A brief overview of the UK Biobank study design is provided below, as
the study design and methods have been reported elsewhere in detail
previously[24]. In short, the data used in this
study came from the baseline survey at 22 assessment centers throughout
England, Wales, and Scotland from 2006 to 2010, a total of 502411
participants (5.5% response rate) aged between 37 and 73 years. Data
from 273325 women were available for our study, we excluded 478
participants with incomplete data on the number of live births and 352
participants who prefer not to answer. Among them, we considered only
the subjects above 40 years of age at recruitment, as there are few
deaths at younger ages[25] (Supplementary Figure
1). As a result, a total of 272494 women (99.7%) were included in this
study. All participants provided written informed consent, and the study
was approved by the North West Multi-Centre Research Ethics Committee
and the Tulane University (New Orleans, LA, USA) Biomedical Committee
Institutional Review Board.