Table 4.
Selected sleep variables during the first 7 h of sleep after lights-out and statistical comparisons in eight men, eight women taking hormonal contraceptives, and eight naturally cycling women in the mid-follicular and mid-luteal phases of their menstrual cycles
| Variable | Women | Men | Statistical comparisons | |||
|---|---|---|---|---|---|---|
| Follicular | Luteal | Contraceptives | ANOVA§ | Paired t test Follicular vs. luteal | ||
| Total sleep time (min) | 398(7) | 395(14) | 387(20) | 384(30)‡ | F2,21= 0·5 | t(7) = 0·7 |
| P = 0·6 | P = 0·5 | |||||
| Sleep efficiency (%) | 95(2) | 94(4) | 92(5) | 91(7) | F2,21= 1·1 | t(7) = 0·1 |
| P = 0·3 | P = 0·9 | |||||
| Sleep onset latency (min) | 11(3) | 11(6) | 19(11) | 15(8) | F2,21= 1·8 | t(7) = 0·31 |
| P = 0·2 | P = 0·8 | |||||
| Latency to stage 3 sleep (min) | 14(6) | 9*(2) | 12(4) | 10(2) | F2,21= 2·3 | t(7) = 2·8 |
| P = 0·1 | P = 0·03 | |||||
| Latency to REM sleep (min) | 70(12) | 80(16) | 62(23) | 76(23) | F2,21= 1·7 | t(7) = 1·3 |
| P = 0·2 | P = 0·2 | |||||
| Stage 2 sleep (%) | 42(6) | 45(6) | 45(3) | 42(4) | F2,21= 0·9 | t(7) = 1·7 |
| P = 0·4 | P = 0·13 | |||||
| Slow wave sleep (%) | 25(6) | 26†(6) | 18(4) | 22(6) | F2,21= 3·6 | t(7) = 0·1 |
| P = 0·045 | P = 0·9 | |||||
| REM sleep (%) | 22(3) | 19(3) | 21(3) | 19(6) | F2,21= 1·0 | t(7) = 2·2 |
| P = 0·38 | P = 0·07 | |||||
Values are means (s.d.).
*
Significantly different from follicular phase values, paired t test
†
Significantly different from values for women taking contraceptives, Tukey post hoc test, P = 0.05
‡
Large s.d. because one man spent more than 1 h awake in the second half of the night
§
Men vs. women taking hormonal contraceptives vs. naturally cycling women in the luteal phase.