Table 7.

Multivariable hazard ratios (HR) and 95 % confidence intervals (CIs) for risk of ovarian cancer by tertiles of parent estrogens and estrogen metabolite pathways

Estrogen/EM	Cases (n = 67)	Subcohort (n = 416)	HR 95 % CI
Total parents (E1 t + E2)
T1	15	137	1.00
T2	24	137	1.26 (0.62, 2.54)
T3	28	142	1.72 (0.87, 3.39)
p trend			0.12
Estrone (E1)
T1	17	138	1.00
T2	23	137	1.08 (0.54, 2.15)
T3	27	141	1.47 (0.75, 2.87)
p trend			0.25
Estradiol (E2)
T1	15	137	1.00
T2	25	137	1.45 (0.72, 2.92)
T3	27	142	1.68 (0.81, 3.47)
p trend			0.16
2-pathway
T1	15	137	1.00
T2	24	137	1.35 (0.67, 2.70)
T3	28	142	1.52 (0.78, 2.97)
p trend			0.23
4-Pathway
T1	15	137	1.00
T2	20	137	1.14 (0.56, 2.34)
T3	32	142	1.76 (0.91, 3.38)
p trend			0.08
16-Pathway
T1	17	137	1.00
T2	20	137	0.91 (0.45, 1.83)
T3	30	142	1.51 (0.78, 2.91)
p trend			0.20

The following tertile categories (T1, T2, T3 pmol/L) determined based on the distribution of each estrogen or estrogen metabolite among the subcohort: total parents (<247.51, 247.51–438.02, >438.02), estrone (<213.86, 213.86–384.12, >384.12), estradiol (<28.99, 28.99–52.20, >52.20), 2-pathway (<101.20, 101.20–141.80, >141.80), 4-pathway (<14.73, 14.73–19.74, >19.74), 16-pathway (<240.02, 240.02–394.53, >394.53); adjusted for clinic and trial participation status