Table 1.
Polysomnographic sleep measures at the MF and ML phases of the menstrual cycle
| Sleep stages during nocturnal sleep episodes | MF (n = 6) | ML (n = 6) | P-value | Sleep stages averaged across all naps | MF (n = 8) | ML (n = 8) | P-value |
|---|---|---|---|---|---|---|---|
| TST (min) | 437.6 ± 8.3 | 423 ± 6.5 | 0.40 | TST (min) | 29.7 ± 1.3 | 29.2 ± 1.3 | 0.50 |
| SE (%) | 93.0 ± 1.2 | 89.5 ± 1.6 | 0.11 | SE (%) | 49.7 ± 2.1 | 48.9 ± 2.3 | 0.65 |
| SOL (min)a | 7.2 ± 1.9 | 16.0 ± 2.7 | 0.02 | SOL (min) | 28.6 ± 1.5 | 28.8 ± 1.6 | 0.84 |
| ROL (min) | 87.2 ± 16.9 | 99.8 ± 19.1 | 0.71 | ROL (min)a | 48.1 ± 1.4 | 50.0 ± 1.5 | 0.05 |
| Stage 1 (%) | 2.8 ± 0.6 | 2.8 ± 0.4 | 0.99 | Stage 1 (%) | 8.3 ± 1.7 | 8.2 ± 1.4 | 0.92 |
| Stage 1 (min) | 12.2 ± 2.7 | 11.9 ±1.6 | 0.87 | Stage 1 (min) | 2.5 ± 0.4 | 2.1 ± 0.2 | 0.14 |
| Stage 2 (%) | 61.4 ± 3.6 | 63.9 ± 2.6 | 0.19 | Stage 2 (%) | 51.1 ± 4.3 | 52.9 ± 4.5 | 0.40 |
| Stage 2 (min) | 269.4 ± 18.3 | 269.8 ± 10.5 | 0.91 | Stage 2 (min) | 18.3 ± 1.3 | 19.5 ± 1.4 | 0.18 |
| SWS (%) | 10.6 ± 2.6 | 10.6 ± 1.2 | 0.91 | SWS (%) | 7.7 ± 1.5 | 7.1 ± 1.2 | 0.36 |
| SWS (min) | 45.4 ± 10.5 | 44.75 ± 5.6 | 0.82 | SWS (min) | 3.4 ± 0.7 | 3.1 ± 0.6 | 0.27 |
| NREM (%) | 71.9 ± 1.7 | 74.4 ± 1.6 | 0.08 | NREM (%) | 58.8 ± 4.4 | 60.0 ± 4.4 | 0.53 |
| NREM (min) | 314.8 ± 8.8 | 314.6 ± 6.8 | 0.96 | NREM (min) | 21.7 ± 1.2 | 22.5 ± 1.4 | 0.23 |
| REM (%)a | 25.2 ± 2.0 | 22.7 ± 1.9 | 0.04 | REM (%) | 11.6 ± 0.9 | 10.3 ± 1.4 | 0.24 |
| REM (min) | 110.6 ± 9.9 | 96.2 ± 8.5 | 0.12 | REM (min) | 5.4 ± 0.4 | 4.5 ± 0.5 | 0.08 |
| WASO (%) | 3.6 ± 1.6 | 5.5 ±1.7 | 0.39 | WASO (%) | 23.4 ± 4.1 | 23.8 ± 3.9 | 0.76 |
| WASO (min) | 17.3 ± 7.8 | 26.2 ± 8.3 | 0.39 | WASO (min) | 14.1 ± 2.8 | 14.2 ± 2.8 | 0.83 |
| MT (%) | 1.2 ± 0.3 | 1.3 ± 0.2 | 0.44 | MT (%) | 0.3 ± 0.1 | 0.3 ± 0.1 | 0.71 |
| MT (min) | 5.6 ± 1.2 | 6.0 ± 1.1 | 0.38 | MT (min) | 0.16 ± 0.0 | 0.16 ± 0.0 | 0.83 |
| MT + WASO (%) | 4.8 ± 1.6 | 6.8 ± 1.5 | 0.32 | MT + WASO (%) | 23.6 ± 4.1 | 24.0 ± 3.9 | 0.75 |
| MT + WASO (min) | 22.9 ± 7.7 | 32.2 ± 7.4 | 0.32 | MT + WASO (min) | 14.3 ± 2.3 | 14.4 ± 2.3 | 0.93 |
| # REM episodes | 4.17 ± 0.3 | 4.5 ± 0.2 | 0.49 | ||||
| mean REM efficiency (%) | 93.3 ± 2.2 | 97.1 ± 0.8 | 0.37 | ||||
| mean REM length (min) | 26.5 ± 1.3 | 21.3 ± 1.5 | 0.07 | ||||
| last REM episode: # fragments | 2.0 ± 0.5 | 1.3 ± 0.2 | 0.40 | ||||
| last REM episode: efficiency (%) | 94.3 ± 4.0 | 97.4 ± 1.9 | 0.42 | ||||
| last REM episode: length (min) | 27.8 ± 3.0 | 17.8 ± 2.2 | 0.07 |
MF, mid-follicular; ML, mid-luteal; TST, total sleep time; SE, sleep efficiency; SOL, sleep onset latency; ROL, REM sleep onset latency; SWS, slow wave sleep; WASO, wake after sleep onset; MT, movement time
All values are mean ± SEM; P-values in left panel provided for one-way repeated measures ANCOVA (with menstrual phase at first visit as covariate); P-values in right panel provided for 2-tailed paired-samples t-tests
a
indicates significant menstrual phase difference (P ≤ 0.05)