Table 1.
Pulmonary function tests.
| Prepregnancy | 13 weeks | 22 weeks | 30 weeks | 9 months postpregnancy | |
|---|---|---|---|---|---|
| TLC | 56% | 54% | 53% | 56% | 59% |
| FVC | 49% | 47% | 41% | 48% | 49% |
| FEV1 | 49% | 51% | 45% | 53% | 52% |
| FEV1/FVC | 99% | 108% | 109% | 110% | 104% |
| DLCO | 34% | 40% | 31% | 37% | 35% |
| O2 requirements with activity and at night | None | 3L NC | 3L NC | 3L NC | None |
Values are represented as fractions of predicted normal values. Normal values are the following (95% confidence interval): TLC, total lung capacity (80%–120%); FVC, forced vital capacity (80%–120%); FEV1, forced expiratory volume at one second (80%–120%); FEV1/FVC, percentage of the FVC expired in one second (within 5% of the predicted ratio); DLCO, diffusing capacity of the lung for carbon monoxide (>60% to <120%).