To identify risk factors for uterine fibroids, a case-control design w
as used to analyze data from control subjects enrolled in the Cancer a
nd Steroid Hormone Study. Case patients were 201 women who reported a
history of uterine fibroids, and control subjects were 1503 women with
out fibroids, individually matched by age to case patients. Reporting
of fibroids was more frequent among premenopausal women women who had
frequent Papanicolaou (Pap) smears, women who used oral contraceptives
and had infrequent Pap smears, and women with higher education. Repor
ting of fibroids was less frequent among women with a lower body mass
index who were current or long-time smokers.