Hussain SM, et al. - Authors evaluated the associations of female reproductive and hormonal factors with incidence of total knee arthroplasty (TKA) for osteoarthritis (OA). They also ascertained if the relationships differ according to overweight/obesity status. Findings suggested an association of reproductive and hormonal factors with risk of knee OA. In women of normal weight at early reproductive age and in non-obese women at midlife, these associations remained significant.