Table 7. Pharmacodynamic surrogates of levonorgestrel activity.
| Period and Variable | TFV/LNG Continuous | TFV/LNG Interrupted | Placebo Continuous | Placebo Interrupted |
|---|---|---|---|---|
| Cervical Mucus Insler Score (normal > 10) | ||||
| Month 1 (N) | 18 | 17 | 5 | 5 |
| Mean (SD) | 6.9 (3.3) | 6.5 (3.6) | 11.0 (3.3) | 12.8 (1.1) |
| Median | 6.0 | 5.0 | 11.0 | 12.0 |
| % with score > 10 | 4 (22.2%) | 3 (17.6%) | 3 (60.0%) | 5 (100%) |
| Month 2 (N) | 16 | 16 | 5 | 5 |
| Mean (SD) | 7.0 (2.8) | 7.5 (3.7) | 10.2 (3.8) | 12.2 (2.5) |
| Median | 7.5 | 5.5 | 13.0 | 13.0 |
| % with score > 10 | 1 (6.3%) | 6 (37.5%) | 3 (60.0%) | 4 (80.0%) |
| Month 3 (N) | 14 | 16 | 5 | 5 |
| Mean (SD) | 6.7 (2.4) | 8.3 (3.4) | 11.4 (2.7) | 12.2 (1.9) |
| Median | 7.0 | 7.0 | 12.0 | 13.0 |
| % with score > 10 | 1 (7.1%) | 6 (37.5%) | 4 (80.0%) | 4 (80.0%) |
| Sperm Migration Assay | ||||
| Month 1 (N) | 13 | 12 | 5 | 4 |
| Normal | 1 (5.6%) | 2 (11.8%) | 5 (100%) | 3 (60.0%) |
| Month 2 (N) | 15 | 11 | 4 | 5 |
| Normal | 4 (22.2%) | 4 (23.5%) | 4 (80.0%) | 5 (100%) |
| Month 3 (N) | 14 | 15 | 5 | 5 |
| Normal | 4 (22.2%) | 4 (23.5%) | (80.0%) | 5 (100%) |
| Monthly Ovulation by Serum Progesterone | ||||
| Month 1 (N) | 18 | 17 | 5 | 5 |
| Ovulation | 7 (38.9%) | 8 (47.1%) | 5 (100%) | 5 (100%) |
| Month 2 (N) | 16 | 16 | 5 | 5 |
| Ovulation | 10 (62.5%) | 8 (50.0%) | 5 (100%) | 5 (100.0%) |
| Month 3 (N) | 14 | 16 | 5 | 5 |
| Ovulation | 10 (71.4%) | 11 (68.8%) | 5 (100%) | 5 (100%) |