Association Of Sleep Patterns During Pregnancy With Birth Outcomes

Objective:sleep is significant for human health and involves a series of biological and physiological processes,the duration and timing of sleep is associated with psychological and physiologic health of human.During pregnancy,change in sleep timing and sleep duration are commonly reported,as physiologic and biochemical changes of pregnancy.Evidence has emerged suggesting that sleep disorders may be associated with complications of pregnancy.However,there is no evidence for relationship between sleep duration and timing during pregnancy with birth outcomes.Therefore,the main purposes of this study were follows:firstly,to investigate the relationship between sleep pattern during pregnancy with birth weight and ponderal Index?PI?of the neonates,and to explore the independent and interactive association of sleep patterns with adverse birth outcomes,including preterm birth?PTB?,low birth weight?LBW?,macrosomia,small for gestational age?SGA?and large for gestational age?LGA?based on the large birth cohort study;secondly,to explore an appropriate sleep patterns during pregnancy and provide evidence for prenatal health care.Methods:1.This study used data from Health Baby Cohort?HBC?,this ongoing cohort enrolls participants at Wuhan Medical and Healthcare Center for Women and Children in Hubei province,China.Between September 2012 and October 2014,11,311participants were enrolled when they gave birth at the hospital.The sleep patterns were analysis based on data from questionnaire,including night sleep timing,wake up timing,night sleep duration,chronotype,midday sleep duration and midday sleep frequency.2.The sleep patterns were categorized into several groups:night sleep timing??22:00,22:00-23:00,23:00-24:00,and?24:00?,wake up timing?<7:00,7:00-8:00,8:00-9:00,and?9:00?,night sleep duration?<8 hours,8-9 hours,9-10 hours,and?10hours?,chronotype?EE,EL,LE,and LL?,midday sleep duration?never,<1.5 hours,1.5-2 hours,and?2 hours?and midday sleep frequency?never,1–6 times per week,and 7 times per week?.We used PI and birth weight of the neonates as dependent variables in the linear regression models analyses to calculate the?and 95%confidence intervals?CIs?for each categories of sleep patterns.For association of sleep patterns with adverse birth outcomes,including PTB,LBW,macrosomia,SGA and LGA,multivariate logistic regression models was used to calculate the ORs and95%CIs for each categories of sleep patterns.3.Restricted Cubic Spline?RCS?was conducted to evaluate the continuous change of ORs for PTB,LBW,macrosomia,SGA,LGA as night sleep timing,wake up timing,night sleep duration and midday sleep duration,and establish the optimal range of sleep patterns.The optimal range of sleep patterns during pregnancy was evaluated by multivariate logistic regression models.Result:1.The average PI and birth weight was 2.60±0.22g/cm3 and 3291.5±458.3g,respectively.The rate of PTB,LBW,macrosomia,SGA and LGA was 6.0%,4.2%,5.7%,6.2%and 9.5%,respectively.The median?IQR?of night sleep timing and wake up timing was 23:00?22:00,23:30?and 8:00?7:00,8:30?,and average night sleep duration and midday sleep duration was 9.2±1.2 hours and 79.5±49.1minutes.2.There was a positive linear relationship between midday sleep duration,night sleep timing,wake up timing and night sleep duration with birth weight(P _{for trend}<0.05).The PI??:0.028;95%CI:0.018,0.039?and birth weight??:70.44,95%CI:49.09,91.80?of the neonate was higher in the women whose chronotype was late bed-late rise compared with early bed-early rise.3.The rate of PTB was lower in the subjects who took midday sleep compared with who never take?5.9%vs 6.6%?,but there is no association between midday sleep duration and frequency with the risk of PTB.Late night sleep timing was related to reduced risk of PTB,the lowest OR was observed among the women who fall asleep later than 24:00?OR:0.65,95%CI:0.51,0.82?.There was an inversely relationship between wake up timing and the risk of PTB,and wake up earlier?<7:00?increased the risk of PTB?OR:1.48,95%CI:1.17,1.87?,and wake up later??9:00?decreased the risk of PTB?OR:0.68,95%CI:0.54,0.86?.Compared with early bed-early rise,the women whose chronotype was late bed-late rise reduced the risk of PTB?OR:0.52,95%CI:0.42,0.64?.We did not find an independent association between night sleep duration with PTB,but the women who sleep?10h tended to reduce risk of PTB when investigated the interactive effect of night sleep timing and duration on PTB.4.The women who took midday sleep had lower rate of LBW and SGA compared with who never take midday sleep.The highest OR of LBW was observed among women who took 1.5-2h midday sleep?OR:0.67,95%CI:0.50,0.90?,but no association for SGA with midday sleep duration.There was an inversely relationship between wake up timing and the risk of LBW and SGA,and later night sleep timing??24:00?might decrease the risk of LBW?OR:0.50,95%CI:0.36,0.68?.Compared with women who waked up between 7:00 and 8:00,waking up earlier?<7:00?elevated the risk of LBW?OR:1.67,95%CI:1.25,2.22?,and waking up later decreased the risk of LBW?OR:0.72,95%CI:0.55,0.96?and SGA?OR:0.71,95%CI:0.57,0.89?.A significant association was observed between longer night sleep duration??10h?and SGA?OR:0.78,95%CI:0.63,0.97?,but not for LBW.Compared with early bed-early rise,the women whose chronotype was late bed-late rise had reduced risk of LBW and SGA.5.The rate of macrosomia and LGA was higher in the subjects who took midday sleep compared with who never take?6.2%vs 4.5%;10.4%vs 8.6%?.Compared with women who never take midday sleep,women with 1.5-2h midday sleep had higher risk of macrosomia?OR:1.54,95%CI:1.17,2.04?and LGA?OR:1.40,95%CI:1.13,1.73?.There is a positive linear relationship between night sleep timing and wake up timing with macrosomia and LGA(P _{for trend}<0.05).Compared with early bed-early rise,the women whose chronotype was late bed-late rise had lower risk of macrosomia?OR:1.31,95%CI:1.06,1.63?and LGA?OR:1.23,95%CI:1.04,1.46?.6.The establishment and evaluation of optimal sleep patterns for pregnancy women.The results of Restricted Cubic Spline?RCS?models analysis showed that women who take midday sleep less than 2 hours,fall asleep later than 23:00,wake up later than 8:00 and night sleep longer than 9 hours,had lower risk of PTB,LBW,macrosomia,SGA and LGA.The rate of general adverse birth outcome was lower in the optimal range of midday sleep duration,sleep timing,wake up timing and night sleep duration.Women with optimal range of sleep and wake up timing had lower risk of general adverse birth outcome.Conclusions:1.The sleep patterns during pregnancy are different with non-pregnant people.Based on large population cohort study,we found that pregnant women fall asleep earlier,and take longer night sleep and midday sleep.The sleep patterns are different between different pre-pregnancy BMI,parity and age.2.Based on large population cohort study,we found that sleep patterns during pregnancy influence the PI and birth weight of the nenates.Maternal sleep patterns are independently associated with the risk of several adverse birth outcomes,including PTB,LBW,macrosomia,SGA and LGA.3.To our knowledge,this is the first large population cohort study exploring the optimal range of sleep patterns during pregnancy,and to provide evidence for prenatal health care.To decrease the risk of adverse birth outcomes,prenatal health professionals should attach importance to sleep health care for pregnant women.