Table 1.
Characteristics of 57,747 participants in the Black Women's Health Study according to history of uterine leiomyomata at baseline, 1995a
| Uterine leiomyomata (UL) |
|||
|---|---|---|---|
| No UL | UL diagnosed at any age | UL diagnosed before age 30 years | |
| Number of participants | 39,209 | 18,538 | 5,651 |
| Age at baseline, yrs (mean) | 36.1 | 44.5 | 39.8 |
| Age at menarche, yrs (mean) | 12.4 | 12.1 | 12.0 |
| Parity, births (mean) | 1.5 | 1.3 | 1.2 |
| Age at first birth, yrs (mean)b | 22.2 | 22.3 | 22.4 |
| Time since last birth, yrs (mean)b | 15.0 | 15.6 | 14.0 |
| Vigorous exercise, hrs/wk (mean) | 2.0 | 2.0 | 2.1 |
| BMI at age 18, kg/m2 (mean)c | 21.5 | 21.5 | 21.6 |
| Current BMI, kg/m2 (mean) | 28.0 | 28.2 | 28.1 |
| Education, yrs (mean) | 14.6 | 14.8 | 14.9 |
| Oral contraceptive use, yrs (mean) | 3.8 | 3.9 | 3.7 |
| Postmenopausal, % | 16 | 19 | 16 |
| Female hormone use, % | 12 | 20 | 19 |
| Family history of breast cancer, % | 7 | 6 | 6 |
| Current smoker, % | 17 | 15 | 15 |
| Alcohol consumption ≥1 drink/day, % | 6 | 5 | 5 |
| Mammogram <1 yr ago, % | 27 | 30 | 25 |
| Physician visit <1 yr ago, % | 86 | 91 | 90 |
a
Means and percentages standardized to age distribution of cohort in 1995. All characteristics assessed in 1995.
b
Restricted to 37,113 participants who were parous at baseline.
c
Restricted to 56,702 participants who reported their weight at age 18.