Table 3.

Regression coefficients from model fits of mammographic measures against height, age at menarche and number of live births, after adjusting for weight of self and co-twin (* estimates and standard errors are multiplied by 100). Associations nominally significant at the .05 level are shown in bold.

		Model I		Model II		Model III			Model IV
		Est. *	(SE)	Est. *	(SE)	Est. *	(SE)		Est. *	(SE)
Height (cm)
Dense area	Self	0.62	(0.25)			0.54	(0.26)		0.54	(0.26)
	Co-twin			0.61	(0.25)	0.53	(0.25)	MZ	0.56	(0.25)
								DZ	0.53	(0.14)
Non-dense area	Self	−1.54	(0.17)			−1.42	(0.17)		2.81	(0.17)
	Co-twin			−0.95	(0.18)	−0.73	(0.17)	MZ	−0.73	(0.17)
								DZ	−0.73	(0.18)
Age at menarche (yrs)
Dense area	Self	2.48	(1.16)			2.61	(1.16)		2.60	(1.15)
	Co-twin			2.68	(1.17)	2.80	(1.15)	MZ	2.87	(1.15)
								DZ	2.64	(1.17)
Non-dense area	Self	−2.20	(0.78)			−2.34	(0.78)		−4.74	(0.78)
	Co-twin			−1.14	(0.78)	−1.37	(0.78)	MZ	−1.32	(0.78)
								DZ	−1.48	(0.80)
Live births (number)
Dense area	Self	−4.16	(1.17)			−4.41	(1.21)		−4.44	(1.21)
	Co-twin			0.17	(0.12)	−0.10	(0.12)	MZ	−0.11	(0.13)
								DZ	−0.07	(0.15)
Non-dense area	Self	4.01	(0.91)			3.98	(0.99)		4.08	(0.83)
	Co-twin			−1.35	(0.93)	−0.09	(1.00)	MZ	0.24	(0.89)
								DZ	−0.67	(1.04)