TABLE 2.

Ovarian cancer survival by reproductive characteristics

Characteristic	Survival, Median (Range), mo	Crude HR (95% CI)*	aHR (95% CI)*†
Age at menarche, y
<12	56 (1–30)	Reference	Reference
12	52 (8–371)	0.98 (0.70–1.37)	1.04 (0.74–1.47)
13	50 (2–359)	0.86 (0.62–1.21)	1.01 (0.72–1.43)
≥14	67 (3–386)	0.77 (0.55–1.09)	0.95 (0.67–1.35)
Menstrual regularity
Regular	56 (1–386)	Reference	Reference
Irregular	72 (3–346)	0.77 (0.54–1.10)	0.99 (0.69–1.42)
Ever used OCs
No	46 (1–386)	Reference	Reference
Yes	81 (3–375)	0.51 (0.39–0.66)	0.71 (0.53–0.97)
Ever pregnant
No	60 (7–386)	Reference	Reference
Yes	56 (1–375)	1.15 (0.87–1.51)	0.76 (0.57–1.01)
Ever live birth
No	60 (7–386)	Reference	Reference
Yes	56 (1–375)	1.13 (0.86–1.47)	0.80 (0.60–1.06)
No. births
None	60 (7–386)	Reference	Reference
1	89 (11–375)	0.83 (0.56–1.24)	0.72 (0.48–1.08)
2	60 (3–341)	1.05 (0.75–1.47)	0.78 (0.55–1.11)
3	44 (2–335)	1.30 (0.93–1.83)	0.88 (0.62–1.26)
4+	41 (1–371)	1.29 (0.93–1.80)	0.81 (0.57–1.14)
Ever had tubal ligation
No	68 (1–375)	Reference	Reference
Yes	56 (3–386)	0.64 (0.43–0.93)	0.90 (0.60–1.34)
Lifetime duration of breastfeeding
None	61 (1–386)	Reference	Reference
<1 y	50 (2–339)	1.31 (1.00–1.70)	1.00 (0.76–1.32)
1–2 y	76 (8–341)	0.75 (0.47–1.19)	0.68 (0.43–1.08)
≥2 y	29 (8–297)	1.48 (0.89–2.47)	0.92 (0.54–1.58)

^*HRs and 95% CIs computed using Cox proportional hazards models.

^†Adjusted for FIGO stage, age at diagnosis, and histology.