Table 2.

Characteristics of Invasive Epithelial Ovarian Cancer Cases and Controls, by Race/Ethnicity, North Carolina Ovarian Cancer Study, 1999–2008

	Whites						African Americans
	Cases (n = 746)		Controls (n = 868)		ORa	95% CI	Cases (n = 111)		Controls (n = 189)		ORa	95% CI
	No.	%	No.	%			No.	%	No.	%
Age, years
20–39	38	5.1	81	9.3			11	9.9	22	11.6
40–49	136	18.2	170	19.6			23	20.7	46	24.3
50–59	239	32.0	261	30.1			37	33.3	67	35.4
60–69	232	31.1	240	27.6			31	27.9	40	21.2
70–74	101	13.5	116	13.4			9	8.1	14	7.4
Age at menarche, years
<12	181	24.4	157	18.2	1.00	Referent	28	25.5	53	28.0	1.00	Referent
≥12	562	75.6	708	81.8	0.67	0.53, 0.86	82	74.5	136	72.0	1.08	0.63, 1.85
Missing data	3		3				1		0
No. of pregnancies								11
0	120	16.1	87	10.0	1.00	Referent	14	12.6	11	5.8	1.00	Referent
1–2	319	42.8	348	40.1	0.62	0.45, 0.85	31	27.9	71	37.6	0.34	0.14, 0.82
≥3	307	41.2	433	49.9	0.45	0.33, 0.62	66	59.5	107	56.6	0.44	0.19, 1.05
P-trend					<0.0001		0		0		0.25
Age at first pregnancy, years
<20	173	27.6	202	25.9	1.00	Referent	56	58.3	94	52.8	1.00	Referent
20–24	276	44.1	333	42.7	0.93	0.72, 1.21	30	31.3	52	29.2	0.98	0.56, 1.72
25–29	137	21.9	151	19.4	1.09	0.80, 1.49	8	8.3	19	10.7	0.73	0.30, 1.79
30–34	31	5.0	79	10.1	0.50	0.31, 0.79	1	1.0	10	5.6	0.18	0.02, 1.45
≥35	9	1.4	14	1.8	0.77	0.33, 1.84	1	1.0	3	1.7	0.65	0.07, 6.45
Missing data	120		89				15		11
P-trend					0.0004						0.15
Age at last pregnancy, years
<20	19	3.0	18	2.3	1.00	Referent	11	11.7	13	7.3	1.00	Referent
20–24	134	21.4	147	18.9	0.79	0.39, 1.57	24	25.5	35	19.8	0.82	0.31, 2.14
25–29	233	37.3	258	33.1	0.76	0.38, 1.49	25	26.6	51	28.8	0.57	0.22, 1.45
30–34	161	25.8	230	29.5	0.60	0.30, 1.18	22	23.4	48	27.1	0.54	0.21, 1.40
≥35	78	12.5	126	16.2	0.53	0.26, 1.08	12	12.8	30	16.9	0.43	0.15, 1.23
Missing data	121		89				17		12
P-trend					<0.0001						0.04
Ever breastfeeding
No	521	69.8	542	62.4	1.00	Referent	75	67.6	135	71.4	1.00	Referent
Yes	225	30.2	326	37.6	0.73	0.59, 0.90	36	32.4	54	28.6	1.16	0.69, 1.93
Missing data	0		0				0		0
Tubal ligation
No	559	75.0	579	66.8	1.00	Referent	77	69.4	93	49.2	1.00	Referent
Yes	186	25.0	288	33.2	0.68	0.54, 0.84	34	30.6	96	50.8	0.43	0.26, 0.71
Missing data	1		1				0		0
Duration of oral contraceptive use, years
Never use	244	34.5	239	28.3	1.00	Referent	47	43.9	58	32.2	1.00	Referent
<1	99	14.0	92	10.9	1.09	0.77, 1.52	15	14.0	14	7.8	1.36	0.59, 3.14
1–<5	166	23.4	228	27.0	0.75	0.57, 0.99	24	22.4	57	31.7	0.54	0.28, 1.04
≥5	199	28.1	285	33.8	0.73	0.55, 0.96	21	19.6	51	28.3	0.53	0.27, 1.03
Missing data	38		24				4		9
Use of menopausal hormones
No	276	37.0	456	52.6	1.00	Referent	75	68.8	148	78.3	1.00	Referent
Yes	470	63.0	411	47.4	1.85	1.50, 2.28	34	31.2	41	21.7	1.54	0.90, 2.66
Missing data	0		1				2		0
Hysterectomy
No	537	72.2	667	76.9	1.00	Referent	82	73.9	145	76.7	1.00	Referent
Yes	207	27.8	200	23.1	1.22	0.97, 1.54	29	26.1	44	23.3	1.07	0.61, 1.87
Missing data	2		1				0		0
History of infertility
No	651	87.3	783	90.2	1.00	Referent	102	91.9	175	92.6	1.00	Referent
Yes	95	12.7	85	9.8	1.38	1.01, 1.89	9	8.1	14	7.4	1.13	0.47, 2.73
Missing data	0		0				0		0
History of endometriosis
No	650	87.7	793	92.3	1.00	Referent	109	98.2	184	98.4	1.00	Referent
Yes	91	12.3	66	7.7	1.76	1.26, 2.46	2	1.8	3	1.6	1.16	0.19, 7.08
Missing data	5		9				0		2
First-degree family history of breast or ovarian cancer
No	582	78.1	720	83.1	1.00	Referent	69	62.2	159	84.1	1.00	Referent
Yes	163	21.9	146	16.9	1.33	1.04, 1.71	42	37.8	30	15.9	3.15	1.82, 5.45
Missing data	1		2				0		0
Talc use
No	328	59.6	325	61.0	1.00	Referent	45	54.2	75	56.0	1.00	Referent
Yes	222	40.4	208	39.0	1.04	0.82, 1.33	38	45.8	59	44.0	1.19	0.68, 2.09
Missing data	196		335				28		55
Body mass indexb 1 year before diagnosis or interview
<25	312	43.3	369	43.7	1.00	Referent	17	15.9	31	17.1	1.00	Referent
25–<30	212	29.4	256	30.3	0.96	0.76, 1.22	26	24.3	58	32.0	0.84	0.39, 1.78
30–<35	114	15.8	124	14.7	1.08	0.80, 1.45	22	20.6	43	23.8	0.94	0.43, 2.07
≥35	83	11.5	95	11.3	1.04	0.75, 1.45	42	39.3	49	27.1	1.62	0.79, 3.35
Missing data	25		24				4		8
Height, m
<1.6	195	26.2	242	27.9	1.00	Referent	25	22.7	57	30.2	1.00	Referent
1.6–<1.7	430	57.8	483	55.8	1.13	0.90, 1.42	64	58.2	102	54.0	1.48	0.84, 2.62
≥1.7	119	16.0	141	16.3	1.11	0.81, 1.51	21	19.1	30	15.9	1.74	0.83, 3.65
Missing data	2		2				1		0

Abbreviations: CI, confidence interval; OR, odds ratio.

^aAdjusted for age.

^bWeight (kg)/height (m)².