Magnitude of the impact of hot flashes on sleep in perimenopausal women  Massimiliano de Zambotti, Ph.D., Ian M. Colrain, Ph.D., Harold S. Javitz, Ph.D., Fiona C. Baker, Ph.D.  Fertility and Sterility  Volume 102, Issue 6, Pages 1708-1715.e1 (December 2014) DOI: 10.1016/j.fertnstert.2014.08.016 Copyright © 2014 American Society for Reproductive Medicine Terms and Conditions

Figure 1 Calculation of the amount of time spent awake that is associated with the presence of hot flashes. The stages of sleep (awake, REM, N1, N2, N3) are represented (top) as a function of time (hypnogram), as obtained from the PSG recording from one participant. Above the hypnogram, 3 physiological hot flashes (defined as an increase in skin conductance >2 μmho in 30 seconds) are marked. Below the hypnogram, the skin-conductance signal for the 3 hot flashes is plotted with a time resolution of 20 minutes (from 5 minutes before to 15 minutes after the onset of the hot flashes); the PSG sleep stages for each of the 40 epochs (30 seconds each) within the 20-minute window are displayed under each hot flash. Hot flashes HF#1 and HF#3 were included in the calculation of the amount of time spent awake in association with hot flashes (HF-associated wake[obj]) as the sum of the minutes of PSG time awake associated with each hot flash (6.5 minutes [HF#1] + 11.5 minutes [HF#3]). For this night, the total amount of awake time associated with hot flashes was 18 minutes. The hot-flash impact index (time awake associated with hot flashes as a percentage of total wakefulness after sleep onset) was calculated as 32.17 %. HF#2 was not included in the calculation of HF-associated wake[obj] because the awake period started more than 1 minute before the start of a rise in skin conductance, making the association between the hot flash and the awakening unclear. Fertility and Sterility 2014 102, 1708-1715.e1DOI: (10.1016/j.fertnstert.2014.08.016) Copyright © 2014 American Society for Reproductive Medicine Terms and Conditions

Figure 2 Amount of time awake associated with the presence of hot flashes. Percentage of WASO associated with hot flashes for each woman, showing the contribution of number of nights and hot flashes to each percentage value. Fertility and Sterility 2014 102, 1708-1715.e1DOI: (10.1016/j.fertnstert.2014.08.016) Copyright © 2014 American Society for Reproductive Medicine Terms and Conditions

Figure 3 Spearman's rank correlation coefficients between subjective and objective assessments of sleep and hot flashes in 34 perimenopausal women. Significant correlations are highlighted in the matrix (*P<.05; **P<.01; ***P<.001). SE= sleep effciency. Fertility and Sterility 2014 102, 1708-1715.e1DOI: (10.1016/j.fertnstert.2014.08.016) Copyright © 2014 American Society for Reproductive Medicine Terms and Conditions

Supplemental Figure 1 Distribution of hot flashes across the night, showing those associated with awakening, those not associated with awakening, and those that occurred when the women were already awake, as a function of hours after “lights-out.” Six hot flashes occurred in hour 9, but these data are not displayed because women were in bed for >8 hours on only one third of the nights (33.3%). Fertility and Sterility 2014 102, 1708-1715.e1DOI: (10.1016/j.fertnstert.2014.08.016) Copyright © 2014 American Society for Reproductive Medicine Terms and Conditions