Table 3.

FOXA1 DNA methylation in relation to reproductive factors among women with ER− cancer

	N	Coefficient	95% CI	P
(A) Parous vs. Nulliparous
AA	139	0.172	(0.025, 0.319)	0.022
EA	83	−0.062	(−0.208, 0.085)	0.403
(B) Number of Births (1, 2, 3+)
AA	117	0.082	(0.010, 0.155)	0.026
EA	52	0.039	(−0.072, 0.151)	0.481
(C) Number of Births (1, 2, 3+) stratified by history of breastfeeding (BF)
AA, no BF	68	0.115	(0.031, 0.199)	0.008
AA, yes BF	49	0.058	(−0.083, 0.198)	0.412
EA, no BF	24	0.031	(−0.120, 0.181)	0.679
EA, yes BF	28	0.052	(−0.130, 0.234)	0.563

Linear regression was performed to evaluate associations between DNA methylation levels at cg04932551 (log-transformed beta values) and (A) parity (yes/no); (B) number of births among parous women (1, 2, or 3+); and (C) birth count (1, 2, or 3+) stratified by history of breastfeeding (yes/no). AA and EA women were assessed separately. Regression models were adjusted for age at diagnosis. Regression coefficients are listed for the indicated comparisons in A, B, and C