Sleep variable
Total
PTB
PTB
Model 1 Model 1 Model 2 Model 2 Model 3 Model 3
OR (95% CI) OR (95% CI) OR (95% CI)
<15 weeks <15 weeks
Sleep qualitya Sleep qualitya
PSQI≤5 PSQI≤5 4572 (84.5) 1 1 1
PSQI>5 PSQI>5 840 (15.5) 1.56 (0.81,1.64) 1.16 (0.81,1.66) 1.15 (0.80,1.64)
Sleep duration (h)b Sleep duration (h)b
≤7 ≤7 4572 (84.5) 1.15 (0.57,2.30) 1.10 (0.55,2.23) 1.09 (0.54,2.20)
8-9 8-9 840 (15.5) 1 1 1
10 10 4572 (84.5) 1.02 (0.75,1.39) 1.03 (0.75,1.41) 1.03 (0.75,1.41)
≥11 ≥11 840 (15.5) 0.97 (0.68,1.41) 0.99 (0.68,1.45) 1.01 (0.69,1.57)
Napping (h)c Napping (h)c
0 0 4572 (84.5) 0.56 (0.18,1.78) 0.53 (0.17,1.70) 0.55 (0.17,1.75)
1-30 1-30 840 (15.5) 1 1 1
31-60 31-60 4572 (84.5) 1.11 (0.60,2.06) 1.12 (0.60,2.10) 1.09 (0.58,2.05)
61-90 61-90 840 (15.5) 0.93 (0.29,2.96) 0.88 (0.27,2.82) 0.60 (0.19,1.91)
90 90 4572 (84.5) 0.67 (0.21,2.12) 0.60 (0.19,1.91) 0.59 (0.18,1.90)
24-28 weeks 24-28 weeks
Sleep qualitya Sleep qualitya
PSQI≤5 PSQI≤5 4572 (84.5) 1 1 1
PSQI>5 PSQI>5 840 (15.5) 1.10 (0.79,1.54) 1.12 (0.80,1.57) 1.11 (0.79,1.56)
Sleep duration (h)b Sleep duration (h)b
≤7 ≤7 4572 (84.5) 1.78 (1.13,2.79) 1.79 (1.11,2.87) 1.80 (1.12,2.89)
8-9 8-9 840 (15.5) 1 1 1
10 10 4572 (84.5) 0.98 (0.71,1.35) 0.98 (0.70,1.36) 0.96 (0.69,1.33)
≥11 ≥11 840 (15.5) 0.53 (0.30,0.92) 0.52 (0.30,0.92) 0.53 (0.30,0.93)
Napping (h)c Napping (h)c
0 0 4572 (84.5) 1.05 (0.72,1.54) 1.07 (0.73,1.57) 1.09 (0.74,1.60)
1-30 1-30 840 (15.5) 1 1 1
31-60 31-60 4572 (84.5) 0.87 (0.60,1.26) 0.89 (0.61,1.29) 0.89 (0.62,1.30)
61-90 61-90 840 (15.5) 1.25 (0.78,1.98) 1.28 (0.80,2.05) 1.29 (0.80,2.07)
90 90 4572 (84.5) 0.77 (0.46,1.28) 0.79 (0.47,1.34) 0.81 (0.48,1.36)