Table 4.

Breast cancer risk, menopausal status, and history of bilateral oophorectomy, by age at diagnosis

Age at diagnosis, yPairs (n)Menopausala %Menopausal OR (95%CI)bPOophorectomy (%)Oophorectomy; OR (95%CI)bP
≤302760.4n/ac0.2n/ac
31–355671.51.43 (0.54–2.74)0.470.51.00 (0.20–4.96)1.00
36–407114.90.62 (0.37–1.02)0.063.00.23 (0.10–0.51)0.0004
41–456079.70.75 (0.52–1.09)0.134.50.36 (0.20–0.66)0.001
46–5038425.00.55 (0.39–0.79)0.0019.10.35 (0.20–0.60)0.0002
≥5030981.40.53 (0.33–0.88)0.0117.00.46 (0.29–0.72)0.0006
All2,85415.80.65 (0.53–0.79)<0.00014.90.38 (0.29–0.50)<0.0001
  • aMenopausal includes natural, surgical, medication- and radiation-induced menopause, cases and controls combined.

  • bEstimates are univariate ORs.

  • cn/a = estimates could not be generated because there were too few individuals who were menopausal (n = 2) or had an oophorectomy (n = 1) for age at diagnosis ≤ 30.