Table 2.

Analyses of association of possible risk factors with age at menopause by Cox proportional hazards model with robust estimate for family relations

	Premutation						Non-carrier

Factors	Univariate		Multivariate		Final model		Univariate		Multivariate		Final model
	HR	p-value	HR	p-value	HR	p-value	HR	p-value	HR	p-value	HR	p-value
Genetic
FMR1: Risk index by repeat	1.26	<0.001 ^*	1.43	<0.001 ^*	1.63	<0.001 ^*	-	-	-	-	1	NA
Mean menopausal age 1^st degree relatives	0.97	0.02 ^*			0.98	0.24	0.90	0.007 ^*	0.91	0.01 ^*	0.91	0.01 ^*
Environmental
Smoking (ever)	1.30 ^a	0.048 ^*	1.34	0.02 ^*	1.35^a	0.02 ^*	1.44^a	0.03 ^*	1.46	0.03 ^*	1.46	0.03 ^*
BMI	0.98 ^a	0.056					1.00^a	0.87
Reproductive
Menarche	1.04 ^a	0.41					1.05^a	0.3054
Parity	0.85 ^a	0.25					0.92^a	0.5673
Hormone use (ever)	1.14 ^a	0.34					0.99^a	0.9272
Confounders
Age at interview	1.02	0.003 ^*					1.02	0.01 ^*
Ascertainment site	1.52	0.004 ^*	1.92	<0.001 ^*	1.77	<0.001 ^*	1.93	<0.001 ^*	1.99	<0.001 ^*	1.99	<0.001 ^*

HR: Hazard ratio; FMR1: Fragile X mental retardation 1;

significant at level α=0.05;

all environmental and reproductive factors were adjusted for the FMR1 risk group at univariate analysis; Multivariate, only significantly associated factors are shown; Final model shows all variables selected for our model based on significant association for either premutation model or non-carrier model to improve comparability. HR>1 indicate increased odds for an earlier menopause (risk factor), HR <1 indicate a longer time to menopause (protective factor).