Table 1a. Age and age-standardized baseline characteristics according height (inches) among participants in the Nurses’ Health Study (N=118,072) and Nurses’ Health Study II (N=115,142).

	NHS (1976)			NHSII (1989)
	≤ 62 in. (n=26729)	64 in. (n=19965)	≥67 in. (n=23943)	≤ 62 in. (n=21856)	64 in. (n=18448)	≥67 in. (n=30614)
Means (SD)
Age a	42.8 (7.3)	42.4 (7.3)	41.7 (7.1)	34.1(4.6)	34.0(4.6)	33.7(4.7)
Height (inches)	61.3 (1.0)	64.0 (0.0)	67.9 (1.2)	61.2 (1.2)	64.0 (0.0)	68.1 (1.3)
Age at first birth (years) b	25.1 (3.3)	25.1 (3.3)	25.3(3.4)	25.4 (4.1)	25.4 (4.1)	25.6 (4.0)
Parity	3.6 (7.0)	3.6 (6.9)	3.5 (6.9)	2.1 (0.9)	2.1 (0.9)	2.1 (0.9)
Alcohol intake (g/day)	5.6 (10.0)	6.4 (10.4)	6.9 (11.1)	2.6 (5.0)	3.0 (5.9)	3.3 (6.0)
BMI at age 18 (kg/m2)	21.7 (3.0)	21.4 (3.0)	21.1 (3.1)	21.4 (3.9)	21.2 (3.8)	20.7 (4.1)
Current BMI (kg/m2)	24.1 (4.3)	23.8 (4.1)	23.6 (4.0)	24.2 (4.7)	24.1 (4.7)	23.8 (4.8)
Weight change since age 18, kg	5.7 (9.2)	6.3 (9.5)	7.2 (10.7)	6.7 (9.6)	7.5 (10.5)	8.7 (11.7)
Age at menarche (years)	12.3 (1.5)	12.5 (1.4)	12.8 (1.5)	12.2 (1.5)	12.3 (1.4)	12.6 (1.4)
Percentages
History of benign breast disease	18	18	19	8	8	8
Irregular menstrual cycles ages 18- 22	23	23	23	24	23	24
Current hormone therapy use c	32	34	35	82	82	81
Former smoker	47	45	40	20	21	23
Current smoker	32	32	35	14	13	14
Birth weight ≥ 8.5 lbs	5	7	12	5	9	16
Parous	93	94	92	72	72	69
Premenopausal	71	72	72	97	97	97
Ever oral contraceptive use	46	48	48	82	84	83
Family history of breast cancer	6	6	7	5	6	6

Note: Values are means (SD) or percentages and are standardized to the age distribution of the study population.

^aValue is not age adjusted

^bamong parous women

^camong postmenopausal women