MATERNAL CHRONOTYPE DURING PREGNANCY AS A PREDICTOR OF SLEEP DIFFICULTIES IN EARLY CHILDHOOD

Oral Session 3
Sunday, April 29, 2018 | 10:40am-12:10pm | Room 342B

10:40am-10:55am
MATERNAL CHRONOTYPE DURING PREGNANCY AS A PREDICTOR OF SLEEP DIFFICULTIES IN EARLY CHILDHOOD

Authors:
Outi Saarenpää-Heikkilä (Finland)*
Isabel Morales-Muñoz (Finland)
Timo Partonen (Finland)
Anneli Kylliäinen (Finland)
Pirjo Pölkki (Finland)
Tarja Porkka-Heiskanen (Finland)
Tiina Paunio (Finland)
Juulia Paavonen (Finland)

Introduction

Chronotype is a construct reflecting individual differences in diurnal preference, and it is thought to be a trait that contributes to individual differences in sleep-wake timing. Chronotype is often divided into “morning”, “intermediate”, and “evening” types. Previous studies with children have found that evening-types exhibit greater sleep problems than morning-types, and consequently it is associated with negative social consequences. However, infant sleep quality can be modulated by infant characteristics, such as chronotype, but also by external factors, such as parental characteristics. To this end, we aimed to examine the effect of parental chronotype on children’s sleep quality in the early childhood. To the best of our knowledge, this is the first study aiming to examine the role of parental chronotype as a potential risk factor for sleeping problems of infants.

Materials and methods

This study was based on a longitudinal CHILD-SLEEP birth cohort, with several measurement points. We used the information regarding parental questionnaires during pregnancy and the sleep measures of the infants at 3, 8, 18 and 24 months. In total, 1220 mothers, 1116 fathers, 993 infants at 3 months, 990 infants at 8 months, 958 children at 18 months, and 777 children at 24 months were analyzed. Parental chronotype during pregnancy was measured using a 6-item version of the Horne-Östberg Morningness-Eveningness Questionnaire (MEQ). Morningness-eveningness dimension (i.e., diurnal preference) was examined with the total sum score, and a cut-off of ≤12 was used to indicate evening-type. Concerning children´s sleep, both the Brief Infant Sleep Questionnaire (BISQ) and the Infant Sleep Questionnaire (ISQ) were filled by the parents at each time point. More specifically, we created the following variables regarding sleep quality problems: i) short sleep in total; ii) slow development of circadian rhythm; iii) long sleep-onset latency; iv) late bedtime; v) high frequency of night awakenings; and vi) other sleep difficulties.

Results

Our main results showed that maternal eveningness preference during pregnancy was associated with children´s circadian rhythm development at all the time points. More specifically, maternal evening-type was related to a slower circadian rhythm development at 3, 8 and 18 months. Furthermore, maternal eveningness preference was associated with other sleep quality problems in children, such as long sleep-onset latency at 3, 18 and 24 months, late bedtime at 3, 8 and 18 months, and sleep difficulties at 24 months; and maternal evening-type was related to late bedtime at 3, 8 and 18 months, sleep difficulties at 8 months, and to long sleep-onset at 18 and 24 months. Interestingly, paternal diurnal preference and/or paternal evening-type were not associated with any of the sleep quality problems in the children at any time point.

Conclusions

Maternal eveningness preference during pregnancy, and more specifically maternal evening-type, can be considered a potential risk factor for the onset of a slower circadian rhythm development in early childhood.

Acknowledgements

We would like to thank all the families that participated in the CHILD-SLEEP birth cohort. We are also grateful for the nurses at the maternity clinics who introduced the study to the families. The project was funded by the Academy of Finland (# 308588; # 134880 and #253346 to TP; and #277557 to OSH), Gyllenberg foundation (TP), Yrjö Jahnsson Foundation, Foundation for Pediatric Research, Finnish Cultural Foundation, the Competitive Research Financing of the Expert Responsibility area of Tampere University Hospital, Arvo ja Lea Ylppö Foundation, and Doctors’ Association in Tampere.