Table 4.
Associations between infertility and endometrial cancer incidence
| Cancer cases | Person-years | Age-adjusted | Multivariablea | |||
|---|---|---|---|---|---|---|
| HR (95% CI) | p value | HR (95% CI) | p value | |||
| Infertility | ||||||
| No infertility | 5797 | 63,265,993 | 1.00 (reference) | . | 1.00 (reference) | . |
| Infertility | 315 | 1,676,408 | 1.55 (1.39–1.74) | < 0.001 | 1.25 (1.11–1.40) | < 0.001 |
| Infertility and related diagnoses | ||||||
| No diagnosis | 5651 | 62,380,847 | 1.00 (reference) | . | 1.00 (reference) | . |
| Ovulatory disturbances | 57 | 363,077 | 1.52 (1.17–1.97) | 0.002 | 1.45 (1.12–1.88) | 0.005 |
| Endometriosis | 89 | 522,069 | 1.00 (0.81–1.24) | 0.985 | 0.94 (0.76–1.17) | 0.584 |
| Infertility | 258 | 1,351,728 | 1.51 (1.33–1.71) | < 0.001 | 1.21 (1.07–1.38) | 0.003 |
| Infertility and ovulatory disturbances | 33 | 149,925 | 3.33 (2.37–4.70) | < 0.001 | 2.90 (2.05–4.08) | < 0.001 |
| Infertility and endometriosis | 24 | 174,755 | 1.14 (0.76–1.70) | 0.534 | 0.87 (0.58–1.30) | 0.503 |
p < 0.05 is significant in all analyses. The dots represent the reference category
aAdjusted for age, calendar time, education level, country of birth, parity and age at first birth, salpingectomy and bilateral oophorectomy