Table 3.

Associations of reproductive history and exogenous hormone use with endometrial cancer

	Cases	Controls	OR1	95% CI	OR2	95% CI
Age at menarche, years
<11	124	342	1.00	Reference	1.00	Reference
11–12	308	1184	0.67	0.51, 0.88	0.69	0.52, 0.92
13–14	271	1142	0.62	0.47, 0.80	0.68	0.52, 0.90
≥15	105	451	0.59	0.43, 0.81	0.66	0.38, 1.08
Missing3	3	5
Ptrend						0.03
Parity
Parous	662	2685	1.00	Reference	1.00	Reference
Nulliparous	143	419	1.34	1.08, 1.66	1.38	1.11, 1.72
Missing3	6	20
Number of births4
1	146	598	1.00	Reference	1.00	Reference
2	154	743	0.86	0.67, 1.11	0.82	0.63, 1.07
3	152	543	1.14	0.88, 1.48	1.04	0.78, 1.37
4	103	343	1.23	0.92, 1.66	1.04	0.76, 1.43
≥5	107	458	0.93	0.69, 1.25	0.75	0.55, 1.04
Ptrend						0.23
Age at first birth, years4
<20	273	1082	1.00	Reference	1.00	Reference
20–24	234	875	1.08	0.89, 1.32	1.13	0.91, 1.40
25–29	113	418	1.08	0.84, 1.40	1.14	0.86, 1.50
≥30	34	283	0.48	0.33, 1.40	0.49	0.32, 0.74
Missing3	8	27
Ptrend						0.03
Age at last birth, years4 5
<25	71	260	1.00	Reference	1.00	Reference
25–29	109	362	1.21	0.85, 1.71	1.34	0.91, 1.97
30–34	83	391	0.80	0.56, 1.15	1.12	0.73, 1.70
≥35	59	360	0.63	0.42, 0.92	0.87	0.55, 1.38
Missing3	3	15
Ptrend						0.40
Tubal ligation6
No	89	203	1.00	Reference	1.00	Reference
Yes	31	101	0.68	0.41, 1.12	1.00	0.56, 1.77
Missing3	33	123
OC duration, years7
Never use	207	685	1.00	Reference	1.00	Reference
<1	109	408	0.88	0.60, 1.29	0.86	0.58, 1.28
1–4	146	530	0.87	0.61, 1.23	0.85	0.59, 1.23
≥5	101	679	0.42	0.26, 0.67	0.44	0.27, 0.70
Missing3	139	400
Ptrend						0.04
Estrogen-only menopausal hormone use8, 9, 10
Never	484	1831	1.00	Reference	1.00	Reference
Ever	63	275	0.90	0.67, 1.21	1.00	0.72, 1.39
Missing3	20	146
Estrogen-only menopausal hormone duration of use, years8, 9, 10
0	484	1831	1.00	Reference	1.00	Reference
1–4	48	252	0.76	0.55, 1.06	0.85	0.60, 1.22
≥5	15	31	1.77	0.93, 3.35	2.08	1.06, 4.06
Missing3	20	146
Ptrend						0.03

OC=oral contraceptives.

¹Adjusted for age, study, menopausal status,

²Adjusted for age, study, menopausal status, body mass index, age at menarche, parity, ever use of oral contraceptives, and smoking status

³Number missing within studies included in the analysis

⁴Analysis restricted to parous women

⁵Analysis of participants from studies BWHS, EDGE, FHCRC, WISE studies

⁶Analysis of participants from CCS, EDGE, NYUWHS studies

⁷Analysis of participants from BWHS, CCS, EDGE, FHCRC, MEC, WISE studies

⁸Analysis restricted to postmenopausal women

⁹Analysis of participants from AARP, BWHS, CCS, EDGE, MEC, and WISE studies