Table 4.
Direction of association for female reproductive health indicators with risk of COPD-related hospitalisation/death and spirometry measures
| Reproductive health indicator | COPD-related hospitalisation/death | FEV1 | FVC | FEV1/FVC |
| Age at menarche | ||||
| <12 years | = | = | ↓ | ↓ |
| 12–15 years | NA | NA | NA | NA |
| >15 years | ↑ | ↓ | ↓ | = |
| Menopause status | ||||
| No | NA | NA | NA | NA |
| Yes | = | ↓ | ↓ | = |
| Age at natural menopause | ||||
| <47 years | ↑ | ↓ | ↓ | = |
| 47–49 years | = | = | = | = |
| 50–52 years | NA | NA | NA | NA |
| >52 years | = | = | = | = |
| Parity, binary | ||||
| Nulliparous | = | ↓ | ↓ | ↑ |
| Parous | NA | NA | NA | NA |
| Parity, ordered categories | ||||
| 0 | NA | NA | NA | NA |
| 1 | = | = | ↑ | ↓ |
| 2 | = | ↑ | ↑ | ↓ |
| 3 | = | ↑ | ↑ | ↓ |
| >3 | ↑ | ↑ | ↑ | ↓ |
| PCOS/ovarian cysts | ||||
| No | NA | NA | NA | NA |
| Yes | ↑ | = | = | ↑ |
| Endometriosis | ||||
| No | NA | NA | NA | NA |
| Yes | = | = | = | ↑ |
| Oral contraception | ||||
| Never used | NA | NA | NA | NA |
| Ever used | ↓ | ↑ | ↑ | = |
| Years of oral contraception | ||||
| 0 | NA | NA | NA | NA |
| 1 | = | = | = | = |
| 2-4 | = | ↑ | ↑ | ↑ |
| 5-9 | = | ↑ | ↑ | ↑ |
| 10-15 | ↓ | ↑ | ↑ | = |
| >15 | ↓ | ↑ | = | = |
| Hormone replacement therapy | ||||
| Never used | NA | NA | NA | NA |
| Ever used | ↑ | = | = | ↑ |
| Years of hormone replacement therapy | ||||
| 0 | NA | NA | NA | NA |
| 1-2 | ↑ | = | = | ↑ |
| 3-5 | = | = | = | = |
| 6-10 | = | = | = | = |
| >10 | = | = | = | = |
| Gynaecological surgery | ||||
| No | NA | NA | NA | NA |
| Hysterectomy | ↑ | = | = | ↑ |
| Bilateral oophorectomy | = | = | = | = |
| Both | ↑ | = | ↓ | ↑ |
COPD, chronic obstructive pulmonary disease; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity; NA, not applicable where the category is the reference group; PCOS, polycystic ovary syndrome.