Table 2.

Sleep architecture and sleep position during late pregnancy

	Average	Range
Total sleep time (min)	378.9 ± 76.7	155.5–594.5
Sleep efficiency (%)	78.8 ± 10.4	40.9–96.9
Sleep latency (min)	11.0 (5.5, 20.5)	0.5–195.5
%TST N3	31.5 ± 12.5	2.0–84.9
%TST REM	15.6 ± 6.1	0.0–30.1
%TST in position
Supine	24.2 (7.4, 40.3)	0.0–100.0
Left	36.1 (22.6, 48.6)	0.0–98.9
Right	35.6 (18.2, 49.4)	0.0–100.0
Prone	0.0 (0.0, 0.0)	0.0–59.4
Position changes	9.7 ± 4.6	0–27
Times out of bed	1.0 (1.0, 2.0)	0–9
Initial time in sleep onset position before repositioning (min)	51.5 (10.0, 72.5)	0.5–492.0
Overall %TST in sleep onset position	44.5 ± 20.8	(0.2–100.0)

Note. n = 187. Values given as M ± SD, Mdn (IQR) or n (%). %TST = percentage of total sleep time, REM = rapid eye movement.