[Mobile phone use in early pregnant and infant sleep-wake behaviour in 6 months: a cohort study]

Objective: To describe the epidemiological characteristics of mobile phone use in early pregnancy, and to explore the relationship between pregnancy mobile use and infant sleep-wake behavior. Methods: During February 2015 to August 2016, 2 212 subjects who had their first antenatal examination at Maanshan Maternity and Child Health Hospital were recruited in this cohort study and followed until postpartum for 6 months. Information of phone use was collected through questionnaire in the third trimester. There were 1 779 pregnant reported hours of mobile phone use in the questionnaire. A total of 1 951 parent reported the night-wake times. Data on night-wake behavior in infants was collected during the 6 months study. Questionnaires were completed by parents when taking the physical examination. More than 3 times per night was defined as the night-wake frequency. Unconditional multivariate logistic regression was applied to analyze the association of pregnancy time of mobile phone use and the infant night-wake frequencies. Results: In this cohort study, the average age of 2 212 pregnant women was (26.95±3.82) years, with 1 983 of them were followed up to the time of delivery. The incidence of night-wake frequency was 28.3% (553/1 951) among these 6-month-old infants. After adjusted for feeding factors in the first trimester, frequencies of using the phone as "3 to 4 hour per day" and "5 hour and above per day" were both positively associated with the frequencies of night-wake behavior in infants. The adjusted OR (95%CI) were 1.49 (1.07-2.07) and 1.79 (1.31-2.46), respectively. Conclusions: The mobile phone use during pregnancy was associated with night-wake of infants. Mobile phone should be rationally used during pregnancy.