Table 4.

Associations Between Urinary Phytoestrogens and Average Menstrual Cycle Length

		<26 days			26–35 Days	>35 days			Continuous
		OR	95% CI			OR	95% CI		β b	95% CIb
Genistein	Unadjusted	1.07	0.93	1.23	Ref	1.08	0.88	1.32	-0.006	-0.046	0.033
	Adjusteda	1.04	0.86	1.25	Ref	1.12	0.83	1.50	0.006	-0.044	0.055
Daidzein	Unadjusted	1.06	0.92	1.22	Ref	1.03	0.84	1.27	-0.017	-0.057	0.022
	Adjusteda	1.02	0.85	1.23	Ref	1.02	0.76	1.37	-0.008	-0.058	0.042
O-DMA	Unadjusted	0.98	0.87	1.10	Ref	0.98	0.83	1.17	-0.020	-0.053	0.014
	Adjusteda	0.90	0.78	1.05	Ref	1.00	0.79	1.26	0.005	-0.041	0.041
Equol	Unadjusted	1.06	0.87	1.29	Ref	0.94	0.69	1.28	-0.044	-0.100	0.013
	Adjusteda	0.97	0.76	1.24	Ref	0.92	0.59	1.44	-0.039	-0.110	0.030
Total Isoflavones	Unadjusted	1.05	0.90	1.21	Ref	1.05	0.85	1.30	-0.017	-0.058	0.027
	Adjusteda	1.03	0.88	1.22	Ref	1.03	0.80	1.33	-0.016	-0.060	0.028
Enterodiol	Unadjusted	1.09	0.93	1.30	Ref	0.98	0.77	1.24	-0.028	-0.075	0.018
	Adjusteda	1.08	0.89	1.32	Ref	1.02	0.76	1.36	-0.013	-0.066	0.039
Enterolactone	Unadjusted	1.07	0.92	1.25	Ref	0.96	0.78	1.18	-0.034	-0.077	0.008
	Adjusteda	1.07	0.89	1.28	Ref	1.02	0.79	1.31	-0.016	-0.061	0.030
Total Lignans	Unadjusted	1.08	0.91	1.29	Ref	0.95	0.75	1.20	-0.040	-0.087	0.007
	Adjusteda	1.08	0.88	1.31	Ref	1.00	0.76	1.32	-0.023	-0.074	0.029
Total Phytoestrogens	Unadjusted	1.11	0.91	1.35	Ref	0.97	0.74	1.29	-0.043	-0.098	0.012
	Adjusteda	1.11	0.89	1.37	Ref	0.95	0.69	1.30	-0.041	-0.099	0.016

Abbreviations: CI, confidence interval; O-DMA, O-desmethylangolensin; OR, odds ratio.

^a Models adjusted for age, BMI, race, urinary creatinine, exercise (questionnaire), supplement use (yes/no), lipids, lead, cadmium, cotinine, parity conditional on gravidity, frequency of alcohol consumption, sum of the other phytoestrogens (log).

^b β and 95% CIs calculated by β/10; interpreted as: the change in cycle length (by day) per 10% increase in phytoestrogen concentration.