Effects of co-sleeping on the sleep pattern in young preschoolers: an observational cross-sectional study

Effects of co-sleeping on the sleep pattern in young preschoolers: an observational cross-sectional study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Effects of co-sleeping on the sleep pattern in young preschoolers: an observational cross-sectional study Felipe Garrido, Juan-Luis González-Caballero, Pilar García, Maria-Lorella Gianni, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3464020/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 14 Feb, 2024 Read the published version in European Journal of Pediatrics → Version 1 posted 10 You are reading this latest preprint version Abstract Purpose This study aimed to investigate the association between co-sleeping practiced during the first year of life and preschoolers' sleep patterns. Methods A prospective, cross-sectional study was designed to analyze including preschoolers between the ages of 12 and 30 months. The Brief Infant Sleep Questionnaire validated in Spanish was used to measure sleep quality. A latent class analysis was performed to identify qualitative subgroups in the sample and explore the effects of co-sleeping and other variables. Results The sleep patterns of 276 children were finally analyzed. A total of 181 (65.6%) mothers reported having practiced co-sleeping with their children. The latent class analysis identified a two-class solution with two different sleep patterns. One of them showed a worse quality sleep pattern. This pattern, defined as "Sleep-Disordered Pattern", showed a significant association with having practiced co-sleeping during the first year of life. In the logistic regression model, having practiced co-sleeping during the first year resulted to be independently associated with the "Sleep-Disordered Pattern" (odds ratio 2.83). Conclusions Based on the present findings co-sleeping during the first year of life appears to be associated with poor sleep patterns of young preschoolers. Co-sleeping Sleep pattern Preschool Children Infants Figures Figure 1 INTRODUCTION Sleep patterns and behaviours of children are influenced by several factors, including biological, cultural, social, and family backgrounds [1; 2]. Establishing a healthy sleep pattern during the first year of life and the early preschool period contributes to late optimal development [ 3 ]. Sleep difficulties impact health outcomes, including obesity risk, and are among the most frequent reasons for consultation in clinical practice [4; 5]. Co-sleeping during the first months of life benefits parents and their babies [ 6 ]. Its role in facilitating successful breastfeeding has been widely acknowledged, so the term breast-sleeping instead of co-sleeping has been proposed [ 7 ]. Moreover, from an anthropological point of view, co-sleeping positively modulates affective and psychomotor development [ 8 ]. However, co-sleeping has been questioned due to a potential increased risk of sudden infant death, particularly associated with unsafe sleeping practices (i.e., parental smoking, recent alcohol consumption, and sofa sharing). According to the American Academy of Pediatrics (AAP) recommendation, co-sleeping in the same bedroom, next to the parent’s bed but on a specific surface, reduces the risk of sudden infant death syndrome by up to 50% [ 9 ]. On the other hand, this risk is increased when babies sleep alone in the same bed as their parents [9; 10]. Studies investigating the relationship between co-sleeping and sleep patterns in infancy have reported inconsistent results indicating any association or the occurrence of more awakenings and prolonged sleep-in lighter stages [11; 12]. To our knowledge, data concerning the effect of co-sleeping on sleep patterns in older ages are limited. Iwata et al. found no statistical association between the practice of co-sleeping and the sleep pattern of a group of 5-year-old children or their parents [ 1 ]. Our study aimed to investigate the association of co-sleeping, practiced during the first year of life, with the sleep pattern during the early years of preschoolers. The hypothesis to be tested was that co-sleeping during the first year of life would not be associated with preschoolers' sleep pattern. METHODS A descriptive, observational, and cross-sectional study was conducted, including a convenient sample of parents of preschoolers aged 12–30 months. The Ethics Committee of the University of Navarra approved the study (code 2022.025). Recruitment of participants was carried out through the outpatient clinics of pediatric health care centers and children's schools in Spain. Data was collected through an online questionnaire designed in Spanish, available on the SurveyMonkey® platform. The questionnaire included an introductory part of the study, and a total of 32 questions, requiring approximately 10 minutes to be answered. All parents participated voluntarily and completed an informed consent before answering the questions. The first part of the questionnaire was designed using the modified Delphi method (22 questions). An online and anonymous reactive Delphi technique was used, where three authors (PG, FG, JLG) with expertise in pediatrics, neurodevelopment, and epidemiology reacted to a previously prepared survey (11–14). Consensus on a final version of the survey was reached after three rounds in which researchers proposed modifications to proposed questions and possible answers. The corrections made by each of the members of the survey development were shared and reviewed anonymously. In the first part of the questionnaire, demographic data, including parents’ age, date of birth and sex of the preschooler, date of answering the questionnaire, and number of children, were collected. Parents were asked whether they consistently practiced co-sleeping. Consistent co-sleeping was defined as co-sleeping at least 3 times a week. Co-sleeping was defined for parents as the practice of sharing their bed, usually parents with their children, during sleeping periods. The definition of co-sleeping was also applied to cases where parents shared their bed using a specific co-sleeping cot. Parents were asked whether they had practiced co-sleeping or not. If the answer was yes, the following question was related to the time (in months) co-sleeping had been practiced. The remaining questions about co-sleeping can be consulted in Appendix 1. Parents were also asked whether their babies had been breastfed and how long. The second part of the questionnaire contained the BISQ-E, based on the BISQ (Brief Infant Sleep Questionnaire) [ 13 ]. The BISQ is a questionnaire widely used in the literature and validated to assess children´s sleep between 6 and 36 months. The BISQ-E has been validated in Spanish for children between 6 and 30 months and includes questions about parental reports on infant daytime and night-time sleep patterns during the previous two weeks [ 5 ]. We have carried out a latent class analysis (LCA) using all the items from the BISQ-E questionnaire as indicators, but the one referring to the position where the child sleeps [ 14 ]. This model allowed us to classify children into patterns characterized by the indicators [ 15 ]. First, we explored the solution with one pattern initial fit parameters. Then, we increased the number of classes until we obtained the best fit for the model. To evaluate the fit, we used several criteria. First, the Akaike Information Criteria (AIC), the Bayesian Information Criterion (BIC), and the Adjusted BIC, where small values of each indicate a better model fit [ 16 – 18 ]. In second place, we used the entropy value, a value comprised between 0 and 1, which measures the uncertainty of the classification obtained for the classes, where values greater than 0.80 indicate a solid separation to identify separate groups [ 19 ]. In third place, we also used the Lo-Mendell-Rubin Adjusted Likelihood Ratio Test (LMRT), and the Bootstrapped Likelihood-Ratio Test (BLRT) [ 20 ], suggesting that, for a p < 0.05, the model with more classes fits the data better than the model with fewer classes. In addition to the statistical fit, we also used the significance and interpretation of the patterns, as well as the probability of the presence of each indicator in the pattern [ 21 ]. Once the profiles were obtained, we calculated the class membership probabilities for everyone. This allowed the identification of a categorical variable within categories by assigning the class with the highest membership probability to each participant. This variable allowed investigating the association between patterns and other characteristics of parents and children not contained in the BISQ-E questionnaire, using chi-square and t-Student test, and finally a logistic regression model. We used Mplus software, version 8.10 (Muthén & Muthén, 3463 Stoner Avenue, Los Angeles, CA 90066, US), to perform LCA [ 22 ] and SPSS, version 29 (IBM Corp., Armonk, NY 10504, US) to perform the descriptive analyses and assess the associations between children characteristics and sleep patterns. In all analyses, we considered a p < 0.05 statistically significant. RESULTS A total of 451 parents responded to the survey. The answers of 175 parents had to be discarded because they were either incomplete or related to preschoolers under 12 or over 30 months. The sleep patterns of 276 children were finally analyzed. The mean maternal age was 35.2 ± 4.4 years. The mean preschoolers' age was 20.4 ± 5.3 months when their mothers participated in the survey. More than half of the mothers (64.9%) did not report any sleeping difficulties of their children when the survey was performed. In contrast, nearly one out of two (55.8%) reported their children had experienced sleeping difficulties in the past. A total of 181 (65.6%) mothers reported having practiced co-sleeping with their children. The demographic data of the sample is shown in Table 1 . Table 1 Demographic summary of participants in the survey. Quantitative variables are summarized as mean (and standard deviation) or median (and interquartile range). Rest of categorical variables are expressed as frequency and percentage (in brackets). Demographic variables Result Mother´s age (years) 35.2 ± 4.4 Father´s age (years) 37.8 ± 5.4 Infant age (months) 20.4 ± 5.3 Sex of infant: - Female - Male 127 (45.4) 149 (53.2) Relevant disease that has caused concern in parents: - Yes - No 15 (5.4) 261 (93.2) Infants´ age transferred to his/her room (in months): 9.0 ± 5.0 Are you worried about your infant sleep pattern? - Yes - No 91 (33) 185 (67) Current difficulties with sleep pattern of your infant? - Yes - No 97 (35.1) 179 (64.9) Have parent had difficulties with sleep pattern of your infant? - Yes - No 154 (55.8) 122 (44.2) Have you practiced co-sleeping during the first year of life (more than 3 times a week)? - Yes - No 191 (69.2) 95 (30.8) Up to what age have you practiced co-sleeping? (in months): 17.8 ± 11.0 Median 17 (ICR 8–24) Planned to practice co-sleeping or started practicing it due to baby requirements: - Planning before birth - Started due to baby requirements 95 (47.0) 107 (53.0) Agreement between parents about co-sleeping? - Yes - No 176 (63.8) 14 (5.1) Has breastfeed the infant? - Yes - No 241 (87.3) 35 (12.7) Age of completion of breastfeeding (in months)? 11.9 ± 7.4 Median 12 (IQR 6–18) The summary of the results of the BISQ-E questionnaire is shown in Table 2 . Half of the preschoolers did not have siblings (49.3%), and in one-third of the cases, the preschooler was the youngest of the family (29.3%). Fifty-nine (21.4%) of preschoolers slept in their parent's bed, or in a cot but in their parent's room (19.2%). The rest slept in their bedroom (47.9%). The position in which they slept was variable (Table 2 ). The average night-time sleep time was 10.1 ± 1.2 hours, while the daytime sleep time (nap) was 2.1 ± 0.7 hours. The median number of nocturnal awakenings was 2 (IQR 1–3). The times (expressed in minutes) to fall asleep at night or to fall asleep once awakened are reported in Table 2 . Many preschoolers fell asleep while eating (19.9%) or in their cot or bed in a room different from their parents (31.9%). Almost 15% needed to fall asleep in their parents' arms, and 10.1% in their parents' bed. More than a third of those surveyed reported children fell asleep between 8 PM and 10 PM. Table 2: Results corresponding to the BISQ-E questionnaire . The results of the categorical variables are expressed with their frequencies and percentages. The results of the quantitative variables are expressed by calculating the means, medians, and interquartile ranges (IQR 25-75) n=244 Recoding of items for LCA Place where the infant sleeps now: Sleeps in the cot/bed, in a separate room Sleeps in the cot/bed, in a shared room with another sibling Sleeps in the crib/bed, in the parents' room Sleeps in parents´ bed 107 (38.8) 25 (9.1) 53 (19.2) 59 (21.4) Sleeping with parents (3,4) Not sleeping with parents (1,2) Position in which the infant sleeps most of the time: On his tummy On his back On his side Not on a define position 62 (22.5) 50 (18.1) 49 (17.8) 75 (27.2) How do you get the infant to fall asleep? Falls asleep while eating In his/her cot/bed in a separate room In his/her cot/bed in the parents' room Rocking him in his/her cot or similar Rocking him/her in parents’ arms Holding him/her in the arms without rocking In the same parent's bed 55 (19.9) 88 (31.9) 14 (5.1) 13 (4.7) 16 (5.8) 25 (9.1) 28 (10.1) Not sleeping in own bed (the rest) Sleeping in own bed (2,3) During weekdays, at what time does your infant usually fall asleep at night? Between 6 PM-8PM Between 8 PM-10 PM Between 10 PM-12 PM 11 (4) 184 (66.7) 49 (17.8) To sleep after 10 pm (3) To sleep before 10 pm (1,2) Do you consider your infant's sleep habits a problem? Yes, a very serious problem. Yes, although a minor problem No, it's not a problem 35 (12.7) 52 (18.8) 129 (46.7) Sleep is an important issue (1) Sleep is not an important issue (2,3) Sleep time overnight (hours) 10.1±1.2 Median 10.5 (IQR 10-11) Sleeping less than 10h at night Sleeping 10h or more at night Sleep time during the day (hours) 2.1±0.7 Median 2.2 (IQR 2-3) Daytime sleep less than 2 hours Daytime sleep 2 hours or more Number of awakenings overnight 2.0±2.4 Median 2 (IQR 1-4) Two or more night-awakenings Less than two night-awakenings Awake time overnight (minutes) 31.4±46.2 Median 9 (IQR 0-45) Awake time overnight more than 10min Awake time overnight 10min or less Time it takes to fall sleep (minutes) 24.8±21.6 Median 20 (IQR 10-20) Time to get sleep more than 20 minutes Time to get sleep 20 minutes or less To perform the latent class analysis, we used as binary indicators the items recoded according to the last column of Table 2 . In this analysis we used the criteria described in the methodology and identified two sleep patterns (Fig. 1 ). Pattern one, represented 41.4% of the sample. This pattern was characterised by children who do not sleep with their parents, sleep in their own bed, sleep for 10 hours or more at night and 2 hours or more during the day, have less than 2 awakenings overnight staying less than 10 minutes awake, and takes less than 20 minutes to fall asleep. They go to bed before 10 PM, and sleep did not look a problem for their parents. All these sleep characteristics are present in this pattern with probabilities between 0.68 and 0.95. This pattern was called by us as "Good-sleep Pattern". Pattern two, represented 58.6% of the sample. In this pattern one or more characteristics of the "Normal Sleep Pattern" were present with a low probability (between 0.11 and 0.45). This meant that children in this pattern used to sleep with their parents, or less than 10 hours, or had two or more awakenings during the night, or took more than 20 min to fall back to sleep or did not sleep in their own bed. This pattern was called by us as "Sleep-Disordered Pattern". Analysis of the relationship between sleep patterns and other characteristics of parents and infants not included in the BISQ-E questionnaire, especially those related to co-sleeping and breastfeeding, are summarised in Table 3 . Past or continued co-sleeping was significantly related to the "Sleep-Disordered Pattern" (p < 0.001). Also in this same pattern, we found a higher probability of having difficulties in putting the baby to sleep at the time of answering the questionnaire (p < 0.001) as in the past (p = 0.015). With respect to the impact of breastfeeding, we also found differences between the two patterns. Infants who had breastfed were more likely to belong to pattern two. Finally, in pattern two ("Sleep-Disordered Pattern") the percentage of parents who were worried about their child sleep quality was higher (p < 0.001), and the father (p = 0.029) or the mother (p = 0.032) reported own sleep problems. Table 3 The relation between the categorical variables was calculated by applying the Chi-square test. Differences between the quantitative variables was calculated through a comparison of means using T-Student test. * 0.001 < p < 0.05; ** p < 0.001 Total (n = 244) Pattern 1 (n = 101) Pattern 2 (n = 143) P value Sociodemographic variables Mother's age (years) [mean ± sd] 35.43 ± 4.32 34.81 ± 4.43 35.87 ± 4.19 0.058 Father's age (years) [mean ± sd] 38.07 ± 5.33 37.62 ± 5.48 38.38 ± 5.22 0.277 Child's age (months) [mean ± sd] 20.25 ± 5.37 21.22 ± 5.59 19.57 ± 5.12 0.018* Child´s sex [n (%)] [Female] 113 (46.3%) 42 (41.6%) 71 (49.7%) 0.213 Serious illness of the child [n (%)] [Yes] 13 (5.3%) 3 (3.0%) 10 (7.0%) 0.168 Siblings of the child [n (%)] [Yes] 115 (47.1%) 62 (61.4%) 53 (37.1%) < 0.001** Variables related to the practice of co-sleeping Have you practiced co-sleeping? [n (%)] [Yes] 164 (67.2%) 44 (43.6%) 120 (83.9%) < 0.001** Is your child still sleeping in your bedroom? [n (%)] [Yes] 113 (46.3%) 7 (6.9%) 106 (74.1%) < 0.001** Do you co-sleep in a specific crib? [n (%)] [Yes] 91 (45.7%) 35 (53.8%) 56 (41.8%) 0.109 Age up to which co-sleeping has occurred [mean ± sd] 17.62 ± 11.11 9.16 ± 6.78 21.14 ± 10.67 < 0.001** Reasons to practice co-sleeping [n (%)] - Decided before birth - In response to the child's requests 85 (46.2%) 99 (53.8%) 28 (53.8%) 24 (46.2%) 57 (43.2%) 75 (56.8%) 0.191 Parents agree on the practice of co-sleeping? [n (%)] [Yes] 161 (93.1%) 44 (93.6%) 117 (92.9%) 0.861 Does the child currently have difficulties sleeping? [n (%)] [Yes] 86 (35.2%) 13 (12.9%) 73 (51.0%) < 0.001** Has the child had difficulty sleeping in the past? [n (%)] [Yes] 136 (55.7%) 47 (46.5%) 89 (62.2%) 0.015* Variables related to breastfeeding Have you given breast milk to your baby? [n (%)] [Yes] 216 (88.5%) 84 (83.2%) 132 (92.3%) 0.027* Until what age have you breastfed your baby? [mean ± sd] 12.26 ± 7.46 8.57 ± 6.06 14.68 ± 7.32 < 0.001** Variables related to parental concerns Are you worried about your child's sleep quality? [n (%)] [Yes] 79 (32.4%) 14 (13.9%) 65 (45.5%) < 0.001** Does the father have sleep problems? [n (%)] [Yes] 39 (16.0%) 10 (9.9%) 29 (20.3%) 0.029* Does the mother have sleep problems?? [n (%)] [Yes] 30 (12.3%) 7 (6.9%) 23 (16.1%) 0.032* We also used a logistic regression model to analyse the joint influence of these characteristics on the two patterns to obtain adjusted ORs (Table 4 ). In this analysis we identified that babies who had co-slept were 2.83 times more likely to be of the "Sleep-Disordered Pattern". They also are 50.20 times more likely to continue sleeping in the parents' bedroom and are 12.78 times more likely to show difficulties putting their child to sleep. Table 4 Logistic regression model to assess the influence of family characteristics on sleep patterns.* 0.001 < p < 0.05; ** p < 0.001 Coef. SE Wald g p OR CI95% Has practiced co-sleeping 1.042 0.422 6.090 1 0.014* 2.835 1.239–6.484 Child currently sleeping in parents bedroom 3.916 0.500 61.247 1 < 0.001** 50.201 18.827–133.859 Child currently have difficulties for sleeping 2.548 0.460 30.743 1 < 0.001** 12.784 5.194–31.468 Constant −2.503 0.409 37.430 1 < 0.000** 0.082 Likelihood ratio test, p < 0.001; R 2 Cox y Snell = 0.505; R 2 McFadden = 0.680 DISCUSSION Contrary to our hypothesis, the present findings indicate that co-sleeping during the first year of life was associated with the sleep pattern quality of young preschoolers. Specifically, co-sleeping resulted in being independently associated with a poor sleep quality pattern. Accordingly, parents who had practiced co-sleeping perceived the sleeping pattern of their children as a severe problem. Compared to parents who had not practiced co-sleeping, they reported their infants slept fewer hours overnight, took longer to fall asleep, and were prone to fall asleep more often in their parents’ arms while eating or in their parents’ bed. From an evolutionary point of view, co-sleeping reflects the importance of providing close and continuous physical contact within the dyad, which contributes to promoting an optimal infant’s development. Moreover, evidence indicates that co-sleeping is associated with promoting successful breastfeeding. Within this scenario, our study's findings apparently contradict, at least partially, the acknowledged beneficial effects associated with co-sleeping. Moreover, at univariate analysis, we also found that breastfeeding was associated with a poor sleep quality pattern. However, considering that infants’ sleep patterns are dynamic and change over the first years of life [ 23 ], it could be speculated that the quality of the sleep pattern of preschoolers whose parents who have practiced co-sleeping may improve over time. In line with this hypothesis, Abdul Jafar et al. conducted a cohort study to evaluate the association between breastfeeding and sleep trajectories from 3 to 54 months [ 24 ]. The authors found that breastfed infants showed increased night awakenings compared to formula-fed infants, with an attenuation of this finding from the age of 18 months, suggesting that the more frequent nocturnal wakefulness shown in breastfed infants may be transient. The effect of co-sleeping during the first months of life on the subsequent sleep pattern of children has not been elucidated yet. In a study on 5-year-old children, Iwata et al. found that co-sleeping, at that age, did not negatively influence the sleep pattern, both for the child and their parents [ 1 ]. Mao et al. conducted a comparative study including babies from 3 to 15 months and found that babies who practiced co-sleeping had more nocturnal awakenings than babies who slept alone [ 11 ]. Fernandez-Miaja et al., in a study carried out on children under two years of age, in a setting very similar to that of our study, reported a mean value of 10.4 hours night sleep and a mean value of 1.9 hours of day sleep time, which are consistent with our findings [ 25 ]. On the contrary, the number of nocturnal awakenings found in our study was higher (2.0 vs 1.2). Persistent co-sleeping has also been associated with mother reports of marital and co-parenting distress and lower maternal emotional availability with infants at bedtime [ 26 ]. However, when addressing co-sleeping, it must be considered that co-sleeping is valued differently according to cultural backgrounds. In Western countries infant solitary sleeping is pursuit aiming at the early achievement of separateness and independent functioning [ 27 ]. Accordingly, Mindell et al., in a study including almost 30,000 children, reported that in Asian countries, children share a room and bed with their parents much more frequently than in Caucasian countries [ 28 ]. Furthermore, In China most parents believe that co-sleeping means security, a happy family intimacy, and a child’s long-term emotional development [ 29 ]. According to our results, a higher percentage of preschoolers fell asleep in their parent’s arms, in their parent’s bed, or eating when they had practiced co-sleeping. In contrast, they fell asleep in their cot or mattress more often if they had not practiced it. Few studies have used latent class analysis in preschool children concerning sleep habits. In a Portuguese cohort of 1092 children, Goncalves et al. identified two behavior patterns at 4 years of age. The pattern with the most sleep difficulties is related to the fact that the mother raises the child without a partner and that the child has no siblings or is not attending daycare [ 30 ]. Levenson et al. assess the sleep pattern of children aged 2–5 years, using latent class analysis to find an optimal four-class solution. They conclude that those with a better sleep pattern than their parents have fewer psychopathological difficulties [ 31 ]. None of these studies assess the effect of co-sleeping or breastfeeding on sleep patterns. None of these studies evaluate the impact of co-sleeping or breastfeeding on sleep patterns. Our study has had several limitations. First, our results have been obtained through a survey based on parents’ perceptions. However, BISQ-E is a well-established, validated instrument used to assess quality of sleep. Secondly, since the questionnaire was distributed through schools or pediatric clinics, people from different sociodemographic areas of Spain could potentially have not been reached. Third, given the cultural differences between countries regarding infant sleep, it may be difficult to extrapolate our results since what is suitable for some parents, such as sharing a bed beyond one year of age, may be understood as inappropriate for other cultures or frustrating. In summary, our study has identified that co-sleeping during the first year of life is associated with young preschoolers’ sleep patterns. Co-sleeping has been shown to benefit different aspects of raising babies, such as supporting breastfeeding or protecting against sudden infant death syndrome when associated with safe sleeping practices [ 26 ]. Further longitudinal studies are needed to gain further insight into the contribution of co-sleeping on the long-term development of sleep patterns’ quality. Declarations Data availability statement : The datasets generated during and/or analyzed during the current study are available from the corresponding author upon reasonable request. Acknowledgments : We´d like to thank all parents participating in this survey for their help in this research. Funding : This study was (partially) funded by the Italian Ministry of Health - Current Research IRCCS. Authors contributions : Literature search : Garrido F, Garcia P. Conceived and designed the analysis : Garrido F, Garcia P. Collected the data : Garrido F, Garcia P, Garrido S, Atance V, Gonzalez L. Contributed data or analysis tools : Garrido F, Gonzalez-Caballero JL. Performed the analysis : Gonzalez-Caballero JL, Garrido F. Data interpretation : Gonzalez-Caballero JL, Garrido F, Cavallaro G, Gianni ML, Raffaelli G. Wrote the paper : Garrido F, Gonzalez-Caballero JL, Cavallaro G, Gianni ML. Competing interest : All authors declare to have no competing interests. Ethics approval : This study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by the Ethics Committee of University of Navarra (Code 2022.025). Consent to participate : Informed consent was obtained from all parents participating in this study. References Iwata S, Iwata O, Matsuishi T (2013) Sleep patterns of Japanese preschool children and their parents: implications for co-sleeping. Acta Paediatr 102:e257-262 Field T (2017) Infant sleep problems and interventions: A review. Infant Behav Dev 47:40–53 Cassanello P, Ruiz-Botia I, Diez-Izquierdo A, Cartanya-Hueso A, Martinez-Sanchez JM, Balaguer A (2021) How do infants and toddlers sleep in Spain? A cross-sectional study. Eur J Pediatr 180:775–782 Li L, Zhang S, Huang Y, Chen K (2017) Sleep duration and obesity in children: A systematic review and meta-analysis of prospective cohort studies. J Paediatr Child Health 53:378–385 Cassanello P, Diez-Izquierdo A, Gorina N, Matilla-Santander N, Martinez-Sanchez JM, Balaguer A (2018) [Adaptation and study of the measurement properties of a sleep questionnaire for infants and pre-school children]. An Pediatr (Engl Ed) 89:230–237 Buswell SD, Spatz DL (2007) Parent-infant co-sleeping and its relationship to breastfeeding. J Pediatr Health Care 21:22–28 Marinelli KA, Ball HL, McKenna JJ, Blair PS (2019) An integrated analysis of maternal-infant sleep, breastfeeding, and sudden infant death syndrome research supporting a balanced discourse. J Hum Lact 35:510–520 Barry ES (2019) Co-sleeping as a proximal context for infant development: The importance of physical touch. Infant Behav Dev 57:101385 Moon RY, Task Force On Sudden Infant Death S (2016) SIDS and Other Sleep-Related Infant Deaths: Evidence Base for 2016 Updated Recommendations for a Safe Infant Sleeping Environment. Pediatrics 138 Gynaecologists RCoOa (2021) Postnatal care. Co-sleeping risk factors. National Institute for Health and Care Excellence Mao A, Burnham MM, Goodlin-Jones BL, Gaylor EE, Anders TF (2004) A comparison of the sleep–wake patterns of cosleeping and solitary-sleeping infants. Child Psychiatry Hum Dev 35:95–105 Teti DM, Fronberg KM, Fanton H, Crosby B (2022) Infant sleep arrangements, infant-parent sleep, and parenting during the first six months post-partum. Infant Behavior and Development 69:101756 Sadeh A (2004) A brief screening questionnaire for infant sleep problems: validation and findings for an Internet sample. Pediatrics 113:e570-e577 Goodman LA (1974) Exploratory Latent Structure Analysis Using Both Identifiable and Unidentifiable Models. Biometrika 61 Collins LMaL, S.T. (2013) Latent Class and Latent Transition Analysis: With Applications in the Social, Behavioral and Health Sciences. Wiley, New York Akaike H (1974) A new look at the statistical model identification. ITAC 19:716–723 Schwarz G (1978) Estimating the Dimension of a Model. The Annals of Statistics 6 Sclove SL (1987) Application of model-selection criteria to some problems in multivariate analysis. Psychometrika 52:333–343 Celeux G, Soromenho G (1996) An entropy criterion for assessing the number of clusters in a mixture model. Journal of Classification 13:195–212 Lo Y (2001) Testing the number of components in a normal mixture. Biometrika 88:767–778 Nylund KL, Asparouhov T, Muthén BO (2007) Deciding on the number of classes in latent class analysis and growth mixture modeling: A Monte Carlo simulation study. Structural equation modeling: A multidisciplinary Journal 14:535–569 Linda K. Muthén BOM ((1998–2017)) Mplus User’s Guide.Eighth Edition edn. Muthén & Muthén, Los Angeles, CA Sadeh A, Mindell JA, Luedtke K, Wiegand B (2009) Sleep and sleep ecology in the first 3 years: a web-based study. J Sleep Res 18:60–73 Abdul Jafar NK, Tham EKH, Pang WW, Fok D, Chua MC, Teoh OH, Goh DYT, Shek LP, Yap F, Tan KH, Gluckman PD, Chong YS, Meaney MJ, Broekman BFP, Cai S (2021) Association between breastfeeding and sleep patterns in infants and preschool children. Am J Clin Nutr 114:1986–1996 Fernandez Miaja M, Rodriguez Fernandez C, Fernandez Perez ML, Mata Zubillaga D, Miaja Quinones J, Rodriguez Fernandez LM (2015) [Amount of sleep and changes in its patterns in children less than two years old]. An Pediatr (Barc) 82:89–94 Teti DM, Shimizu M, Crosby B, Kim BR (2016) Sleep arrangements, parent-infant sleep during the first year, and family functioning. Dev Psychol 52:1169–1181 D'Souza L, Cassels T (2022) Contextual considerations in infant sleep: Offering alternative interventions to families. Sleep Health Mindell JA, Sadeh A, Wiegand B, How TH, Goh DY (2010) Cross-cultural differences in infant and toddler sleep. Sleep Med 11:274–280 Huang X-n, Wang H-s, Zhang L-j, Liu X-c (2010) Co-sleeping and children's sleep in China. Biological Rhythm Research 41:169–181 Goncalves M, Costa AR, Severo M, Henriques A, Barros H (2023) Sleep patterns in childhood: a longitudinal assessment from the Generation XXI birth cohort. Gac Sanit 37:102293 Levenson JC, Joseph HM, Merranko J, Hafeman DM, Monk K, Goldstein BI, Axelson D, Sakolsky D, Diler RS, Goldstein T, Birmaher B (2023) Sleep patterns among preschool offspring of parents with and without psychopathology: Association with the development of psychopathology in childhood. Bipolar Disord Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 14 Feb, 2024 Read the published version in European Journal of Pediatrics → Version 1 posted Editorial decision: Revision requested 13 Dec, 2023 Reviews received at journal 11 Dec, 2023 Reviews received at journal 04 Dec, 2023 Reviewers agreed at journal 03 Dec, 2023 Reviewers agreed at journal 19 Nov, 2023 Reviewers agreed at journal 08 Nov, 2023 Reviewers invited by journal 24 Oct, 2023 Editor assigned by journal 20 Oct, 2023 Submission checks completed at journal 20 Oct, 2023 First submitted to journal 18 Oct, 2023 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-3464020","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":241580899,"identity":"7d1f481a-5b17-4f7d-a5ed-e08ef143075b","order_by":0,"name":"Felipe Garrido","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAxklEQVRIiWNgGAWjYBAC9gYQacAMYxEBeA7AtEBYRGthAGqRSCBWC//iZ58rCqzldGe+MXvws41BTp6QA3kknhnPPGOQbmx2O8fcsLeNwdiAkAPtJQ4YMzYYHE7cdjvHTILnDEPiBoIOkzj+GaLl5hkzyT9nGOrnE3QYfw/Ulhs8ZtI8FQwJDIQcxiPBUwzUAvTLmbQyaZkKCcMNBLXwH9/M2PDHWs7s+OFtkm8MbOQJhhh6dEgQUg8E/ITcMQpGwSgYBaMAAEu+O64CELbhAAAAAElFTkSuQmCC","orcid":"","institution":"Clínica Universidad de Navarra","correspondingAuthor":true,"prefix":"","firstName":"Felipe","middleName":"","lastName":"Garrido","suffix":""},{"id":241580900,"identity":"2a600f11-4f03-4d48-a1b4-df40cb3693d3","order_by":1,"name":"Juan-Luis González-Caballero","email":"","orcid":"","institution":"University of Cadiz","correspondingAuthor":false,"prefix":"","firstName":"Juan-Luis","middleName":"","lastName":"González-Caballero","suffix":""},{"id":241580901,"identity":"f32ac087-0d3a-4cf0-87a0-d4f078f5d5c4","order_by":2,"name":"Pilar García","email":"","orcid":"","institution":"Jérôme Lejeune Institute","correspondingAuthor":false,"prefix":"","firstName":"Pilar","middleName":"","lastName":"García","suffix":""},{"id":241580902,"identity":"4f881f95-9a69-44be-a387-91344384df3a","order_by":3,"name":"Maria-Lorella Gianni","email":"","orcid":"","institution":"Università degli Studi di Milano","correspondingAuthor":false,"prefix":"","firstName":"Maria-Lorella","middleName":"","lastName":"Gianni","suffix":""},{"id":241580903,"identity":"751ea3fb-722f-401e-b215-2300cc50d98a","order_by":4,"name":"Silvia Garrido","email":"","orcid":"","institution":"Clínica Universidad de Navarra","correspondingAuthor":false,"prefix":"","firstName":"Silvia","middleName":"","lastName":"Garrido","suffix":""},{"id":241580904,"identity":"86828414-9dd3-4c52-8b30-431eaeae3ae7","order_by":5,"name":"Lucia Gonzalez","email":"","orcid":"","institution":"Clínica Universidad de Navarra","correspondingAuthor":false,"prefix":"","firstName":"Lucia","middleName":"","lastName":"Gonzalez","suffix":""},{"id":241580905,"identity":"321b843e-62ca-415f-8bcf-804926ced2df","order_by":6,"name":"Verónica Atance","email":"","orcid":"","institution":"Clínica Universidad de Navarra","correspondingAuthor":false,"prefix":"","firstName":"Verónica","middleName":"","lastName":"Atance","suffix":""},{"id":241580906,"identity":"d378a9fa-eb59-4080-ab09-ca24206e4ead","order_by":7,"name":"Genny Raffaeli","email":"","orcid":"","institution":"Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico","correspondingAuthor":false,"prefix":"","firstName":"Genny","middleName":"","lastName":"Raffaeli","suffix":""},{"id":241580907,"identity":"f8974e6f-7d8c-4324-8ec9-2e148d9f164a","order_by":8,"name":"Giacomo Cavallaro","email":"","orcid":"","institution":"Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico","correspondingAuthor":false,"prefix":"","firstName":"Giacomo","middleName":"","lastName":"Cavallaro","suffix":""}],"badges":[],"createdAt":"2023-10-18 23:44:09","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3464020/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3464020/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00431-024-05429-2","type":"published","date":"2024-02-14T15:00:58+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":45117246,"identity":"2e3c0cb5-bf6c-44b0-90d3-e765a246be9a","added_by":"auto","created_at":"2023-10-23 23:36:59","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":109458,"visible":true,"origin":"","legend":"\u003cp\u003eGraphical representation of the two patterns obtained through the latent class analysis. Pattern 1 is the “Good-Sleep Pattern”, and pattern 2 is the \"Sleep-Disordered Pattern\".\u003c/p\u003e","description":"","filename":"Figure1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3464020/v1/7d55dfa0d1079171635446f5.jpg"},{"id":51322866,"identity":"0589c79d-eae3-4f26-9a65-baddb2e36733","added_by":"auto","created_at":"2024-02-19 15:12:40","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":416122,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3464020/v1/f9edd5ce-5693-4039-b615-46b8ec767dd7.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Effects of co-sleeping on the sleep pattern in young preschoolers: an observational cross-sectional study","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eSleep patterns and behaviours of children are influenced by several factors, including biological, cultural, social, and family backgrounds [1; 2]. Establishing a healthy sleep pattern during the first year of life and the early preschool period contributes to late optimal development [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Sleep difficulties impact health outcomes, including obesity risk, and are among the most frequent reasons for consultation in clinical practice [4; 5].\u003c/p\u003e \u003cp\u003eCo-sleeping during the first months of life benefits parents and their babies [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Its role in facilitating successful breastfeeding has been widely acknowledged, so the term breast-sleeping instead of co-sleeping has been proposed [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Moreover, from an anthropological point of view, co-sleeping positively modulates affective and psychomotor development [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eHowever, co-sleeping has been questioned due to a potential increased risk of sudden infant death, particularly associated with unsafe sleeping practices (i.e., parental smoking, recent alcohol consumption, and sofa sharing). According to the American Academy of Pediatrics (AAP) recommendation, co-sleeping in the same bedroom, next to the parent\u0026rsquo;s bed but on a specific surface, reduces the risk of sudden infant death syndrome by up to 50% [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. On the other hand, this risk is increased when babies sleep alone in the same bed as their parents [9; 10].\u003c/p\u003e \u003cp\u003eStudies investigating the relationship between co-sleeping and sleep patterns in infancy have reported inconsistent results indicating any association or the occurrence of more awakenings and prolonged sleep-in lighter stages [11; 12].\u003c/p\u003e \u003cp\u003eTo our knowledge, data concerning the effect of co-sleeping on sleep patterns in older ages are limited. Iwata et al. found no statistical association between the practice of co-sleeping and the sleep pattern of a group of 5-year-old children or their parents [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eOur study aimed to investigate the association of co-sleeping, practiced during the first year of life, with the sleep pattern during the early years of preschoolers. The hypothesis to be tested was that co-sleeping during the first year of life would not be associated with preschoolers' sleep pattern.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cp\u003eA descriptive, observational, and cross-sectional study was conducted, including a convenient sample of parents of preschoolers aged 12\u0026ndash;30 months. The Ethics Committee of the University of Navarra approved the study (code 2022.025). Recruitment of participants was carried out through the outpatient clinics of pediatric health care centers and children's schools in Spain.\u003c/p\u003e \u003cp\u003eData was collected through an online questionnaire designed in Spanish, available on the SurveyMonkey\u0026reg; platform. The questionnaire included an introductory part of the study, and a total of 32 questions, requiring approximately 10 minutes to be answered. All parents participated voluntarily and completed an informed consent before answering the questions.\u003c/p\u003e \u003cp\u003eThe first part of the questionnaire was designed using the modified Delphi method (22 questions). An online and anonymous reactive Delphi technique was used, where three authors (PG, FG, JLG) with expertise in pediatrics, neurodevelopment, and epidemiology reacted to a previously prepared survey (11\u0026ndash;14). Consensus on a final version of the survey was reached after three rounds in which researchers proposed modifications to proposed questions and possible answers. The corrections made by each of the members of the survey development were shared and reviewed anonymously.\u003c/p\u003e \u003cp\u003eIn the first part of the questionnaire, demographic data, including parents\u0026rsquo; age, date of birth and sex of the preschooler, date of answering the questionnaire, and number of children, were collected. Parents were asked whether they consistently practiced co-sleeping. Consistent co-sleeping was defined as co-sleeping at least 3 times a week. Co-sleeping was defined for parents as the practice of sharing their bed, usually parents with their children, during sleeping periods. The definition of co-sleeping was also applied to cases where parents shared their bed using a specific co-sleeping cot. Parents were asked whether they had practiced co-sleeping or not. If the answer was yes, the following question was related to the time (in months) co-sleeping had been practiced. The remaining questions about co-sleeping can be consulted in Appendix 1. Parents were also asked whether their babies had been breastfed and how long.\u003c/p\u003e \u003cp\u003eThe second part of the questionnaire contained the BISQ-E, based on the BISQ (Brief Infant Sleep Questionnaire) [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. The BISQ is a questionnaire widely used in the literature and validated to assess children\u0026acute;s sleep between 6 and 36 months. The BISQ-E has been validated in Spanish for children between 6 and 30 months and includes questions about parental reports on infant daytime and night-time sleep patterns during the previous two weeks [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eWe have carried out a latent class analysis (LCA) using all the items from the BISQ-E questionnaire as indicators, but the one referring to the position where the child sleeps [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. This model allowed us to classify children into patterns characterized by the indicators [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. First, we explored the solution with one pattern initial fit parameters. Then, we increased the number of classes until we obtained the best fit for the model. To evaluate the fit, we used several criteria. First, the Akaike Information Criteria (AIC), the Bayesian Information Criterion (BIC), and the Adjusted BIC, where small values of each indicate a better model fit [\u003cspan additionalcitationids=\"CR17\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. In second place, we used the entropy value, a value comprised between 0 and 1, which measures the uncertainty of the classification obtained for the classes, where values greater than 0.80 indicate a solid separation to identify separate groups [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. In third place, we also used the Lo-Mendell-Rubin Adjusted Likelihood Ratio Test (LMRT), and the Bootstrapped Likelihood-Ratio Test (BLRT) [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], suggesting that, for a p\u0026thinsp;\u0026lt;\u0026thinsp;0.05, the model with more classes fits the data better than the model with fewer classes. In addition to the statistical fit, we also used the significance and interpretation of the patterns, as well as the probability of the presence of each indicator in the pattern [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eOnce the profiles were obtained, we calculated the class membership probabilities for everyone. This allowed the identification of a categorical variable within categories by assigning the class with the highest membership probability to each participant. This variable allowed investigating the association between patterns and other characteristics of parents and children not contained in the BISQ-E questionnaire, using chi-square and t-Student test, and finally a logistic regression model.\u003c/p\u003e \u003cp\u003eWe used Mplus software, version 8.10 (Muth\u0026eacute;n \u0026amp; Muth\u0026eacute;n, 3463 Stoner Avenue, Los Angeles, CA 90066, US), to perform LCA [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e] and SPSS, version 29 (IBM Corp., Armonk, NY 10504, US) to perform the descriptive analyses and assess the associations between children characteristics and sleep patterns. In all analyses, we considered a p\u0026thinsp;\u0026lt;\u0026thinsp;0.05 statistically significant.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cp\u003e A total of 451 parents responded to the survey. The answers of 175 parents had to be discarded because they were either incomplete or related to preschoolers under 12 or over 30 months. The sleep patterns of 276 children were finally analyzed.\u003c/p\u003e \u003cp\u003eThe mean maternal age was 35.2\u0026thinsp;\u0026plusmn;\u0026thinsp;4.4 years. The mean preschoolers' age was 20.4\u0026thinsp;\u0026plusmn;\u0026thinsp;5.3 months when their mothers participated in the survey. More than half of the mothers (64.9%) did not report any sleeping difficulties of their children when the survey was performed. In contrast, nearly one out of two (55.8%) reported their children had experienced sleeping difficulties in the past. A total of 181 (65.6%) mothers reported having practiced co-sleeping with their children. The demographic data of the sample is shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDemographic summary of participants in the survey. Quantitative variables are summarized as mean (and standard deviation) or median (and interquartile range). Rest of categorical variables are expressed as frequency and percentage (in brackets).\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDemographic variables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eResult\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMother\u0026acute;s age (years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e35.2\u0026thinsp;\u0026plusmn;\u0026thinsp;4.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFather\u0026acute;s age (years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e37.8\u0026thinsp;\u0026plusmn;\u0026thinsp;5.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eInfant age (months)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e20.4\u0026thinsp;\u0026plusmn;\u0026thinsp;5.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex of infant:\u003c/p\u003e \u003cp\u003e- Female\u003c/p\u003e \u003cp\u003e- Male\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e127 (45.4)\u003c/p\u003e \u003cp\u003e149 (53.2)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRelevant disease that has caused concern in parents:\u003c/p\u003e \u003cp\u003e- Yes\u003c/p\u003e \u003cp\u003e- No\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15 (5.4)\u003c/p\u003e \u003cp\u003e261 (93.2)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eInfants\u0026acute; age transferred to his/her room (in months):\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e9.0\u0026thinsp;\u0026plusmn;\u0026thinsp;5.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAre you worried about your infant sleep pattern?\u003c/p\u003e \u003cp\u003e- Yes\u003c/p\u003e \u003cp\u003e- No\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e91 (33)\u003c/p\u003e \u003cp\u003e185 (67)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCurrent difficulties with sleep pattern of your infant?\u003c/p\u003e \u003cp\u003e- Yes\u003c/p\u003e \u003cp\u003e- No\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e97 (35.1)\u003c/p\u003e \u003cp\u003e179 (64.9)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHave parent had difficulties with sleep pattern of your infant?\u003c/p\u003e \u003cp\u003e- Yes\u003c/p\u003e \u003cp\u003e- No\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e154 (55.8)\u003c/p\u003e \u003cp\u003e122 (44.2)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHave you practiced co-sleeping during the first year of life (more than 3 times a week)?\u003c/p\u003e \u003cp\u003e- Yes\u003c/p\u003e \u003cp\u003e- No\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e191 (69.2)\u003c/p\u003e \u003cp\u003e95 (30.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUp to what age have you practiced co-sleeping? (in months):\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e17.8\u0026thinsp;\u0026plusmn;\u0026thinsp;11.0\u003c/p\u003e \u003cp\u003eMedian 17 (ICR 8\u0026ndash;24)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePlanned to practice co-sleeping or started practicing it due to baby requirements:\u003c/p\u003e \u003cp\u003e- Planning before birth\u003c/p\u003e \u003cp\u003e- Started due to baby requirements\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e95 (47.0)\u003c/p\u003e \u003cp\u003e107 (53.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAgreement between parents about co-sleeping?\u003c/p\u003e \u003cp\u003e- Yes\u003c/p\u003e \u003cp\u003e- No\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e176 (63.8)\u003c/p\u003e \u003cp\u003e14 (5.1)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHas breastfeed the infant?\u003c/p\u003e \u003cp\u003e- Yes\u003c/p\u003e \u003cp\u003e- No\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e241 (87.3)\u003c/p\u003e \u003cp\u003e35 (12.7)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge of completion of breastfeeding (in months)?\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e11.9\u0026thinsp;\u0026plusmn;\u0026thinsp;7.4\u003c/p\u003e \u003cp\u003eMedian 12 (IQR 6\u0026ndash;18)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe summary of the results of the BISQ-E questionnaire is shown in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. Half of the preschoolers did not have siblings (49.3%), and in one-third of the cases, the preschooler was the youngest of the family (29.3%). Fifty-nine (21.4%) of preschoolers slept in their parent's bed, or in a cot but in their parent's room (19.2%). The rest slept in their bedroom (47.9%). The position in which they slept was variable (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The average night-time sleep time was 10.1\u0026thinsp;\u0026plusmn;\u0026thinsp;1.2 hours, while the daytime sleep time (nap) was 2.1\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7 hours. The median number of nocturnal awakenings was 2 (IQR 1\u0026ndash;3). The times (expressed in minutes) to fall asleep at night or to fall asleep once awakened are reported in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. Many preschoolers fell asleep while eating (19.9%) or in their cot or bed in a room different from their parents (31.9%). Almost 15% needed to fall asleep in their parents' arms, and 10.1% in their parents' bed. More than a third of those surveyed reported children fell asleep between 8 PM and 10 PM.\u003c/p\u003e \u003cp\u003eTable 2: Results corresponding to the BISQ-E questionnaire\u003cs\u003e.\u003c/s\u003e The results of the categorical variables are expressed with their frequencies and percentages. The results of the quantitative variables are expressed by calculating the means, medians, and interquartile ranges (IQR 25-75)\u003c/p\u003e\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"996\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"52.81124497991968%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.843373493975903%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003en=244\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"36.34538152610442%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eRecoding of items for LCA\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"52.81124497991968%\" valign=\"top\"\u003e\n \u003cp\u003ePlace where the infant sleeps now:\u003c/p\u003e\n \u003col\u003e\n \u003cli\u003eSleeps in the cot/bed, in a separate room\u003c/li\u003e\n \u003cli\u003eSleeps in the cot/bed, in a shared room with another sibling\u003c/li\u003e\n \u003cli\u003eSleeps in the crib/bed, in the parents\u0026apos; room\u003c/li\u003e\n \u003cli\u003eSleeps in parents\u0026acute; bed\u003c/li\u003e\n \u003c/ol\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.843373493975903%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e107 (38.8)\u003c/p\u003e\n \u003cp\u003e25 (9.1)\u003c/p\u003e\n \u003cp\u003e53 (19.2)\u003c/p\u003e\n \u003cp\u003e59 (21.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"36.34538152610442%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003col\u003e\n \u003cli\u003eSleeping with parents (3,4)\u003c/li\u003e\n \u003cli\u003eNot sleeping with parents (1,2)\u003c/li\u003e\n \u003c/ol\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"52.81124497991968%\" valign=\"top\"\u003e\n \u003cp\u003ePosition in which the infant sleeps most of the time:\u003c/p\u003e\n \u003cul\u003e\n \u003cli\u003eOn his tummy\u003c/li\u003e\n \u003cli\u003eOn his back\u003c/li\u003e\n \u003cli\u003eOn his side\u003c/li\u003e\n \u003cli\u003eNot on a define position\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.843373493975903%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e62 (22.5)\u003c/p\u003e\n \u003cp\u003e50 (18.1)\u003c/p\u003e\n \u003cp\u003e49 (17.8)\u003c/p\u003e\n \u003cp\u003e75 (27.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"36.34538152610442%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"52.81124497991968%\" valign=\"top\"\u003e\n \u003cp\u003eHow do you get the infant to fall asleep?\u003c/p\u003e\n \u003col\u003e\n \u003cli\u003eFalls asleep while eating\u003c/li\u003e\n \u003cli\u003eIn his/her cot/bed in a separate room\u003c/li\u003e\n \u003cli\u003eIn his/her cot/bed in the parents\u0026apos; room\u003c/li\u003e\n \u003cli\u003eRocking him in his/her cot or similar\u003c/li\u003e\n \u003cli\u003eRocking him/her in parents\u0026rsquo; arms\u003c/li\u003e\n \u003cli\u003eHolding him/her in the arms without rocking\u003c/li\u003e\n \u003cli\u003eIn the same parent\u0026apos;s bed\u003c/li\u003e\n \u003c/ol\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.843373493975903%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e55 (19.9)\u003c/p\u003e\n \u003cp\u003e88 (31.9)\u003c/p\u003e\n \u003cp\u003e14 (5.1)\u003c/p\u003e\n \u003cp\u003e13 (4.7)\u003c/p\u003e\n \u003cp\u003e16 (5.8)\u003c/p\u003e\n \u003cp\u003e25 (9.1)\u003c/p\u003e\n \u003cp\u003e28 (10.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"36.34538152610442%\"\u003e\n \u003col\u003e\n \u003cli\u003eNot sleeping in own bed (the rest)\u003c/li\u003e\n \u003cli\u003eSleeping in own bed (2,3)\u003c/li\u003e\n \u003c/ol\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"52.81124497991968%\" valign=\"top\"\u003e\n \u003cp\u003eDuring weekdays, at what time does your infant usually fall asleep at night?\u003c/p\u003e\n \u003col\u003e\n \u003cli\u003eBetween 6 PM-8PM\u003c/li\u003e\n \u003cli\u003eBetween 8 PM-10 PM\u003c/li\u003e\n \u003cli\u003eBetween 10 PM-12 PM\u003c/li\u003e\n \u003c/ol\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.843373493975903%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e11 (4)\u003c/p\u003e\n \u003cp\u003e184 (66.7)\u003c/p\u003e\n \u003cp\u003e49 (17.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"36.34538152610442%\"\u003e\n \u003col\u003e\n \u003cli\u003eTo sleep after 10 pm (3)\u003c/li\u003e\n \u003cli\u003eTo sleep before 10 pm (1,2)\u003c/li\u003e\n \u003c/ol\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"52.81124497991968%\" valign=\"top\"\u003e\n \u003cp\u003eDo you consider your infant\u0026apos;s sleep habits a problem?\u003c/p\u003e\n \u003col\u003e\n \u003cli\u003eYes, a very serious problem.\u003c/li\u003e\n \u003cli\u003eYes, although a minor problem\u003c/li\u003e\n \u003cli\u003eNo, it\u0026apos;s not a problem\u003c/li\u003e\n \u003c/ol\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.843373493975903%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e35 (12.7)\u003c/p\u003e\n \u003cp\u003e52 (18.8)\u003c/p\u003e\n \u003cp\u003e129 (46.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"36.34538152610442%\"\u003e\n \u003col\u003e\n \u003cli\u003eSleep is an important issue (1)\u003c/li\u003e\n \u003cli\u003eSleep is not an important issue (2,3)\u003c/li\u003e\n \u003c/ol\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"52.81124497991968%\" valign=\"top\"\u003e\n \u003cp\u003eSleep time overnight (hours)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.843373493975903%\" valign=\"top\"\u003e\n \u003cp\u003e10.1\u0026plusmn;1.2\u003c/p\u003e\n \u003cp\u003eMedian 10.5 (IQR 10-11)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"36.34538152610442%\"\u003e\n \u003col\u003e\n \u003cli\u003eSleeping less than 10h at night\u003c/li\u003e\n \u003cli\u003eSleeping 10h or more at night\u003c/li\u003e\n \u003c/ol\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"52.81124497991968%\" valign=\"top\"\u003e\n \u003cp\u003eSleep time during the day (hours)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.843373493975903%\" valign=\"top\"\u003e\n \u003cp\u003e2.1\u0026plusmn;0.7\u003c/p\u003e\n \u003cp\u003eMedian 2.2 (IQR 2-3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"36.34538152610442%\"\u003e\n \u003col\u003e\n \u003cli\u003eDaytime sleep less than 2 hours\u003c/li\u003e\n \u003cli\u003eDaytime sleep 2 hours or more\u003c/li\u003e\n \u003c/ol\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"52.81124497991968%\" valign=\"top\"\u003e\n \u003cp\u003eNumber of awakenings overnight\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.843373493975903%\" valign=\"top\"\u003e\n \u003cp\u003e2.0\u0026plusmn;2.4\u003c/p\u003e\n \u003cp\u003eMedian 2 (IQR 1-4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"36.34538152610442%\"\u003e\n \u003col\u003e\n \u003cli\u003eTwo or more night-awakenings\u003c/li\u003e\n \u003cli\u003eLess than two night-awakenings\u003c/li\u003e\n \u003c/ol\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"52.81124497991968%\" valign=\"top\"\u003e\n \u003cp\u003eAwake time overnight (minutes)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.843373493975903%\" valign=\"top\"\u003e\n \u003cp\u003e31.4\u0026plusmn;46.2\u003c/p\u003e\n \u003cp\u003eMedian 9 (IQR 0-45)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"36.34538152610442%\"\u003e\n \u003col\u003e\n \u003cli\u003eAwake time overnight more than 10min\u003c/li\u003e\n \u003cli\u003eAwake time overnight 10min or less\u003c/li\u003e\n \u003c/ol\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"52.81124497991968%\" valign=\"top\"\u003e\n \u003cp\u003eTime it takes to fall sleep (minutes)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.843373493975903%\" valign=\"top\"\u003e\n \u003cp\u003e24.8\u0026plusmn;21.6\u003c/p\u003e\n \u003cp\u003eMedian 20 (IQR 10-20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"36.34538152610442%\"\u003e\n \u003col\u003e\n \u003cli\u003eTime to get sleep more than 20 minutes\u003c/li\u003e\n \u003cli\u003eTime to get sleep 20 minutes or less\u003c/li\u003e\n \u003c/ol\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\u003cbr\u003e\u003cp\u003eTo perform the latent class analysis, we used as binary indicators the items recoded according to the last column of Table \u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. In this analysis we used the criteria described in the methodology and identified two sleep patterns (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Pattern one, represented 41.4% of the sample. This pattern was characterised by children who do not sleep with their parents, sleep in their own bed, sleep for 10 hours or more at night and 2 hours or more during the day, have less than 2 awakenings overnight staying less than 10 minutes awake, and takes less than 20 minutes to fall asleep. They go to bed before 10 PM, and sleep did not look a problem for their parents. All these sleep characteristics are present in this pattern with probabilities between 0.68 and 0.95. This pattern was called by us as \"Good-sleep Pattern\". Pattern two, represented 58.6% of the sample. In this pattern one or more characteristics of the \"Normal Sleep Pattern\" were present with a low probability (between 0.11 and 0.45). This meant that children in this pattern used to sleep with their parents, or less than 10 hours, or had two or more awakenings during the night, or took more than 20 min to fall back to sleep or did not sleep in their own bed. This pattern was called by us as \"Sleep-Disordered Pattern\".\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eAnalysis of the relationship between sleep patterns and other characteristics of parents and infants not included in the BISQ-E questionnaire, especially those related to co-sleeping and breastfeeding, are summarised in Table \u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. Past or continued co-sleeping was significantly related to the \"Sleep-Disordered Pattern\" (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Also in this same pattern, we found a higher probability of having difficulties in putting the baby to sleep at the time of answering the questionnaire (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) as in the past (p\u0026thinsp;=\u0026thinsp;0.015). With respect to the impact of breastfeeding, we also found differences between the two patterns. Infants who had breastfed were more likely to belong to pattern two. Finally, in pattern two (\"Sleep-Disordered Pattern\") the percentage of parents who were worried about their child sleep quality was higher (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), and the father (p\u0026thinsp;=\u0026thinsp;0.029) or the mother (p\u0026thinsp;=\u0026thinsp;0.032) reported own sleep problems.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eThe relation between the categorical variables was calculated by applying the Chi-square test. Differences between the quantitative variables was calculated through a comparison of means using T-Student test. * 0.001\u0026thinsp;\u0026lt;\u0026thinsp;p\u0026thinsp;\u0026lt;\u0026thinsp;0.05; ** p\u0026thinsp;\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal (n\u0026thinsp;=\u0026thinsp;244)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePattern 1 (n\u0026thinsp;=\u0026thinsp;101)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePattern 2 (n\u0026thinsp;=\u0026thinsp;143)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e \u003cp\u003eSociodemographic variables\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMother's age (years) [mean\u0026thinsp;\u0026plusmn;\u0026thinsp;sd]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e35.43\u0026thinsp;\u0026plusmn;\u0026thinsp;4.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e34.81\u0026thinsp;\u0026plusmn;\u0026thinsp;4.43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e35.87\u0026thinsp;\u0026plusmn;\u0026thinsp;4.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.058\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFather's age (years) [mean\u0026thinsp;\u0026plusmn;\u0026thinsp;sd]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e38.07\u0026thinsp;\u0026plusmn;\u0026thinsp;5.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e37.62\u0026thinsp;\u0026plusmn;\u0026thinsp;5.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e38.38\u0026thinsp;\u0026plusmn;\u0026thinsp;5.22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.277\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChild's age (months) [mean\u0026thinsp;\u0026plusmn;\u0026thinsp;sd]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20.25\u0026thinsp;\u0026plusmn;\u0026thinsp;5.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21.22\u0026thinsp;\u0026plusmn;\u0026thinsp;5.59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e19.57\u0026thinsp;\u0026plusmn;\u0026thinsp;5.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.018*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChild\u0026acute;s sex [n (%)] [Female]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e113 (46.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e42 (41.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e71 (49.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.213\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSerious illness of the child [n (%)] [Yes]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13 (5.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (3.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e10 (7.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.168\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSiblings of the child [n (%)] [Yes]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e115 (47.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e62 (61.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e53 (37.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eVariables related to the practice of co-sleeping\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHave you practiced co-sleeping? [n (%)] [Yes]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e164 (67.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e44 (43.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e120 (83.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIs your child still sleeping in your bedroom? [n (%)] [Yes]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e113 (46.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7 (6.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e106 (74.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDo you co-sleep in a specific crib? [n (%)] [Yes]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e91 (45.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e35 (53.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e56 (41.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.109\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge up to which co-sleeping has occurred [mean\u0026thinsp;\u0026plusmn;\u0026thinsp;sd]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e17.62\u0026thinsp;\u0026plusmn;\u0026thinsp;11.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.16\u0026thinsp;\u0026plusmn;\u0026thinsp;6.78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e21.14\u0026thinsp;\u0026plusmn;\u0026thinsp;10.67\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eReasons to practice co-sleeping [n (%)]\u003c/p\u003e \u003cp\u003e- Decided before birth\u003c/p\u003e \u003cp\u003e- In response to the child's requests\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e85 (46.2%)\u003c/p\u003e \u003cp\u003e99 (53.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e28 (53.8%)\u003c/p\u003e \u003cp\u003e24 (46.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e57 (43.2%)\u003c/p\u003e \u003cp\u003e75 (56.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.191\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eParents agree on the practice of co-sleeping? [n (%)] [Yes]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e161 (93.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e44 (93.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e117 (92.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.861\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDoes the child currently have difficulties sleeping? [n (%)] [Yes]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e86 (35.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13 (12.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e73 (51.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHas the child had difficulty sleeping in the past? [n (%)] [Yes]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e136 (55.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e47 (46.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e89 (62.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.015*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eVariables related to breastfeeding\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHave you given breast milk to your baby? [n (%)] [Yes]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e216 (88.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e84 (83.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e132 (92.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.027*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUntil what age have you breastfed your baby? [mean\u0026thinsp;\u0026plusmn;\u0026thinsp;sd]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12.26\u0026thinsp;\u0026plusmn;\u0026thinsp;7.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8.57\u0026thinsp;\u0026plusmn;\u0026thinsp;6.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e14.68\u0026thinsp;\u0026plusmn;\u0026thinsp;7.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eVariables related to parental concerns\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAre you worried about your child's sleep quality? [n (%)] [Yes]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e79 (32.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e14 (13.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e65 (45.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDoes the father have sleep problems? [n (%)] [Yes]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e39 (16.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10 (9.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e29 (20.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.029*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDoes the mother have sleep problems?? [n (%)] [Yes]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30 (12.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7 (6.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e23 (16.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.032*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eWe also used a logistic regression model to analyse the joint influence of these characteristics on the two patterns to obtain adjusted ORs (Table \u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). In this analysis we identified that babies who had co-slept were 2.83 times more likely to be of the \"Sleep-Disordered Pattern\". They also are 50.20 times more likely to continue sleeping in the parents' bedroom and are 12.78 times more likely to show difficulties putting their child to sleep.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eLogistic regression model to assess the influence of family characteristics on sleep patterns.* 0.001\u0026thinsp;\u0026lt;\u0026thinsp;p\u0026thinsp;\u0026lt;\u0026thinsp;0.05; ** p\u0026thinsp;\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCoef.\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSE\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eWald\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eg\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eOR\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eCI95%\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHas practiced co-sleeping\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.042\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.422\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6.090\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.014*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e2.835\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e1.239\u0026ndash;6.484\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChild currently sleeping in parents bedroom\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.916\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e61.247\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001**\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e50.201\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e18.827\u0026ndash;133.859\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChild currently have difficulties for sleeping\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.548\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.460\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e30.743\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001**\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e12.784\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e5.194\u0026ndash;31.468\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eConstant\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026minus;2.503\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.409\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e37.430\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.000**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.082\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"8\" nameend=\"c8\" namest=\"c1\"\u003e \u003cp\u003eLikelihood ratio test, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001; R\u003csup\u003e2\u003c/sup\u003e Cox y Snell\u0026thinsp;=\u0026thinsp;0.505; R\u003csup\u003e2\u003c/sup\u003e McFadden\u0026thinsp;=\u0026thinsp;0.680\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eContrary to our hypothesis, the present findings indicate that co-sleeping during the first year of life was associated with the sleep pattern quality of young preschoolers. Specifically, co-sleeping resulted in being independently associated with a poor sleep quality pattern. Accordingly, parents who had practiced co-sleeping perceived the sleeping pattern of their children as a severe problem. Compared to parents who had not practiced co-sleeping, they reported their infants slept fewer hours overnight, took longer to fall asleep, and were prone to fall asleep more often in their parents\u0026rsquo; arms while eating or in their parents\u0026rsquo; bed.\u003c/p\u003e \u003cp\u003eFrom an evolutionary point of view, co-sleeping reflects the importance of providing close and continuous physical contact within the dyad, which contributes to promoting an optimal infant\u0026rsquo;s development. Moreover, evidence indicates that co-sleeping is associated with promoting successful breastfeeding. Within this scenario, our study's findings apparently contradict, at least partially, the acknowledged beneficial effects associated with co-sleeping. Moreover, at univariate analysis, we also found that breastfeeding was associated with a poor sleep quality pattern.\u003c/p\u003e \u003cp\u003eHowever, considering that infants\u0026rsquo; sleep patterns are dynamic and change over the first years of life [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e], it could be speculated that the quality of the sleep pattern of preschoolers whose parents who have practiced co-sleeping may improve over time. In line with this hypothesis, Abdul Jafar et al. conducted a cohort study to evaluate the association between breastfeeding and sleep trajectories from 3 to 54 months [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. The authors found that breastfed infants showed increased night awakenings compared to formula-fed infants, with an attenuation of this finding from the age of 18 months, suggesting that the more frequent nocturnal wakefulness shown in breastfed infants may be transient.\u003c/p\u003e \u003cp\u003eThe effect of co-sleeping during the first months of life on the subsequent sleep pattern of children has not been elucidated yet. In a study on 5-year-old children, Iwata et al. found that co-sleeping, at that age, did not negatively influence the sleep pattern, both for the child and their parents [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Mao et al. conducted a comparative study including babies from 3 to 15 months and found that babies who practiced co-sleeping had more nocturnal awakenings than babies who slept alone [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Fernandez-Miaja et al., in a study carried out on children under two years of age, in a setting very similar to that of our study, reported a mean value of 10.4 hours night sleep and a mean value of 1.9 hours of day sleep time, which are consistent with our findings [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. On the contrary, the number of nocturnal awakenings found in our study was higher (2.0 vs 1.2). Persistent co-sleeping has also been associated with mother reports of marital and co-parenting distress and lower maternal emotional availability with infants at bedtime [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eHowever, when addressing co-sleeping, it must be considered that co-sleeping is valued differently according to cultural backgrounds. In Western countries infant solitary sleeping is pursuit aiming at the early achievement of separateness and independent functioning [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. Accordingly, Mindell et al., in a study including almost 30,000 children, reported that in Asian countries, children share a room and bed with their parents much more frequently than in Caucasian countries [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. Furthermore, In China most parents believe that co-sleeping means security, a happy family intimacy, and a child\u0026rsquo;s long-term emotional development [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e According to our results, a higher percentage of preschoolers fell asleep in their parent\u0026rsquo;s arms, in their parent\u0026rsquo;s bed, or eating when they had practiced co-sleeping. In contrast, they fell asleep in their cot or mattress more often if they had not practiced it. Few studies have used latent class analysis in preschool children concerning sleep habits. In a Portuguese cohort of 1092 children, Goncalves et al. identified two behavior patterns at 4 years of age. The pattern with the most sleep difficulties is related to the fact that the mother raises the child without a partner and that the child has no siblings or is not attending daycare [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. Levenson et al. assess the sleep pattern of children aged 2\u0026ndash;5 years, using latent class analysis to find an optimal four-class solution. They conclude that those with a better sleep pattern than their parents have fewer psychopathological difficulties [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. None of these studies assess the effect of co-sleeping or breastfeeding on sleep patterns. None of these studies evaluate the impact of co-sleeping or breastfeeding on sleep patterns.\u003c/p\u003e \u003cp\u003eOur study has had several limitations. First, our results have been obtained through a survey based on parents\u0026rsquo; perceptions. However, BISQ-E is a well-established, validated instrument used to assess quality of sleep. Secondly, since the questionnaire was distributed through schools or pediatric clinics, people from different sociodemographic areas of Spain could potentially have not been reached. Third, given the cultural differences between countries regarding infant sleep, it may be difficult to extrapolate our results since what is suitable for some parents, such as sharing a bed beyond one year of age, may be understood as inappropriate for other cultures or frustrating.\u003c/p\u003e \u003cp\u003eIn summary, our study has identified that co-sleeping during the first year of life is associated with young preschoolers\u0026rsquo; sleep patterns. Co-sleeping has been shown to benefit different aspects of raising babies, such as supporting breastfeeding or protecting against sudden infant death syndrome when associated with safe sleeping practices [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Further longitudinal studies are needed to gain further insight into the contribution of co-sleeping on the long-term development of sleep patterns\u0026rsquo; quality.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eData availability statement\u003c/strong\u003e:\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eThe datasets generated during and/or analyzed during the current study are available from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e: We\u0026acute;d like to thank all parents participating in this survey for their help in this research.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e: This study was (partially) funded by the Italian Ministry of Health - Current Research IRCCS.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors contributions\u003c/strong\u003e: \u003cu\u003eLiterature search\u003c/u\u003e: Garrido F, Garcia P. \u003cu\u003eConceived and designed the analysis\u003c/u\u003e: Garrido F, Garcia P. \u003cu\u003eCollected the data\u003c/u\u003e: Garrido F, Garcia P, Garrido S, Atance V, Gonzalez L. \u003cu\u003eContributed data or analysis tools\u003c/u\u003e: Garrido F, Gonzalez-Caballero JL. \u003cu\u003ePerformed the analysis\u003c/u\u003e: Gonzalez-Caballero JL, Garrido F. \u003cu\u003eData interpretation\u003c/u\u003e: Gonzalez-Caballero JL, Garrido F, Cavallaro G, Gianni ML, Raffaelli G. \u003cu\u003eWrote the paper\u003c/u\u003e: Garrido F, Gonzalez-Caballero JL, Cavallaro G, Gianni ML.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interest\u003c/strong\u003e: All authors declare to have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval\u003c/strong\u003e: This study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by the Ethics Committee of University of Navarra (Code 2022.025).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to participate\u003c/strong\u003e: Informed consent was obtained from all parents participating in this study.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eIwata S, Iwata O, Matsuishi T (2013) Sleep patterns of Japanese preschool children and their parents: implications for co-sleeping. Acta Paediatr 102:e257-262\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eField T (2017) Infant sleep problems and interventions: A review. Infant Behav Dev 47:40\u0026ndash;53\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCassanello P, Ruiz-Botia I, Diez-Izquierdo A, Cartanya-Hueso A, Martinez-Sanchez JM, Balaguer A (2021) How do infants and toddlers sleep in Spain? A cross-sectional study. Eur J Pediatr 180:775\u0026ndash;782\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLi L, Zhang S, Huang Y, Chen K (2017) Sleep duration and obesity in children: A systematic review and meta-analysis of prospective cohort studies. J Paediatr Child Health 53:378\u0026ndash;385\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCassanello P, Diez-Izquierdo A, Gorina N, Matilla-Santander N, Martinez-Sanchez JM, Balaguer A (2018) [Adaptation and study of the measurement properties of a sleep questionnaire for infants and pre-school children]. An Pediatr (Engl Ed) 89:230\u0026ndash;237\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBuswell SD, Spatz DL (2007) Parent-infant co-sleeping and its relationship to breastfeeding. J Pediatr Health Care 21:22\u0026ndash;28\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMarinelli KA, Ball HL, McKenna JJ, Blair PS (2019) An integrated analysis of maternal-infant sleep, breastfeeding, and sudden infant death syndrome research supporting a balanced discourse. J Hum Lact 35:510\u0026ndash;520\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBarry ES (2019) Co-sleeping as a proximal context for infant development: The importance of physical touch. Infant Behav Dev 57:101385\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMoon RY, Task Force On Sudden Infant Death S (2016) SIDS and Other Sleep-Related Infant Deaths: Evidence Base for 2016 Updated Recommendations for a Safe Infant Sleeping Environment. Pediatrics 138\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGynaecologists RCoOa (2021) Postnatal care. Co-sleeping risk factors. National Institute for Health and Care Excellence\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMao A, Burnham MM, Goodlin-Jones BL, Gaylor EE, Anders TF (2004) A comparison of the sleep\u0026ndash;wake patterns of cosleeping and solitary-sleeping infants. Child Psychiatry Hum Dev 35:95\u0026ndash;105\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTeti DM, Fronberg KM, Fanton H, Crosby B (2022) Infant sleep arrangements, infant-parent sleep, and parenting during the first six months post-partum. Infant Behavior and Development 69:101756\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSadeh A (2004) A brief screening questionnaire for infant sleep problems: validation and findings for an Internet sample. Pediatrics 113:e570-e577\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGoodman LA (1974) Exploratory Latent Structure Analysis Using Both Identifiable and Unidentifiable Models. Biometrika 61\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCollins LMaL, S.T. (2013) Latent Class and Latent Transition Analysis: With Applications in the Social, Behavioral and Health Sciences. Wiley, New York\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAkaike H (1974) A new look at the statistical model identification. ITAC 19:716\u0026ndash;723\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSchwarz G (1978) Estimating the Dimension of a Model. The Annals of Statistics 6\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSclove SL (1987) Application of model-selection criteria to some problems in multivariate analysis. Psychometrika 52:333\u0026ndash;343\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCeleux G, Soromenho G (1996) An entropy criterion for assessing the number of clusters in a mixture model. Journal of Classification 13:195\u0026ndash;212\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLo Y (2001) Testing the number of components in a normal mixture. Biometrika 88:767\u0026ndash;778\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNylund KL, Asparouhov T, Muth\u0026eacute;n BO (2007) Deciding on the number of classes in latent class analysis and growth mixture modeling: A Monte Carlo simulation study. Structural equation modeling: A multidisciplinary Journal 14:535\u0026ndash;569\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLinda K. Muth\u0026eacute;n BOM ((1998\u0026ndash;2017)) Mplus User\u0026rsquo;s Guide.Eighth Edition edn. Muth\u0026eacute;n \u0026amp; Muth\u0026eacute;n, Los Angeles, CA\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSadeh A, Mindell JA, Luedtke K, Wiegand B (2009) Sleep and sleep ecology in the first 3 years: a web-based study. J Sleep Res 18:60\u0026ndash;73\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAbdul Jafar NK, Tham EKH, Pang WW, Fok D, Chua MC, Teoh OH, Goh DYT, Shek LP, Yap F, Tan KH, Gluckman PD, Chong YS, Meaney MJ, Broekman BFP, Cai S (2021) Association between breastfeeding and sleep patterns in infants and preschool children. Am J Clin Nutr 114:1986\u0026ndash;1996\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFernandez Miaja M, Rodriguez Fernandez C, Fernandez Perez ML, Mata Zubillaga D, Miaja Quinones J, Rodriguez Fernandez LM (2015) [Amount of sleep and changes in its patterns in children less than two years old]. An Pediatr (Barc) 82:89\u0026ndash;94\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTeti DM, Shimizu M, Crosby B, Kim BR (2016) Sleep arrangements, parent-infant sleep during the first year, and family functioning. Dev Psychol 52:1169\u0026ndash;1181\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eD'Souza L, Cassels T (2022) Contextual considerations in infant sleep: Offering alternative interventions to families. Sleep Health\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMindell JA, Sadeh A, Wiegand B, How TH, Goh DY (2010) Cross-cultural differences in infant and toddler sleep. Sleep Med 11:274\u0026ndash;280\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHuang X-n, Wang H-s, Zhang L-j, Liu X-c (2010) Co-sleeping and children's sleep in China. Biological Rhythm Research 41:169\u0026ndash;181\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGoncalves M, Costa AR, Severo M, Henriques A, Barros H (2023) Sleep patterns in childhood: a longitudinal assessment from the Generation XXI birth cohort. Gac Sanit 37:102293\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLevenson JC, Joseph HM, Merranko J, Hafeman DM, Monk K, Goldstein BI, Axelson D, Sakolsky D, Diler RS, Goldstein T, Birmaher B (2023) Sleep patterns among preschool offspring of parents with and without psychopathology: Association with the development of psychopathology in childhood. Bipolar Disord\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"european-journal-of-pediatrics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ejpe","sideBox":"Learn more about [European Journal of Pediatrics](https://www.springer.com/journal/431)","snPcode":"431","submissionUrl":"https://submission.nature.com/new-submission/431/3","title":"European Journal of Pediatrics","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Co-sleeping, Sleep pattern, Preschool Children, Infants","lastPublishedDoi":"10.21203/rs.3.rs-3464020/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3464020/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e \u003cp\u003eThis study aimed to investigate the association between co-sleeping practiced during the first year of life and preschoolers' sleep patterns.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eA prospective, cross-sectional study was designed to analyze including preschoolers between the ages of 12 and 30 months. The Brief Infant Sleep Questionnaire validated in Spanish was used to measure sleep quality. A latent class analysis was performed to identify qualitative subgroups in the sample and explore the effects of co-sleeping and other variables.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe sleep patterns of 276 children were finally analyzed. A total of 181 (65.6%) mothers reported having practiced co-sleeping with their children. The latent class analysis identified a two-class solution with two different sleep patterns. One of them showed a worse quality sleep pattern. This pattern, defined as \"Sleep-Disordered Pattern\", showed a significant association with having practiced co-sleeping during the first year of life. In the logistic regression model, having practiced co-sleeping during the first year resulted to be independently associated with the \"Sleep-Disordered Pattern\" (odds ratio 2.83).\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eBased on the present findings co-sleeping during the first year of life appears to be associated with poor sleep patterns of young preschoolers.\u003c/p\u003e","manuscriptTitle":"Effects of co-sleeping on the sleep pattern in young preschoolers: an observational cross-sectional study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2023-10-23 23:36:54","doi":"10.21203/rs.3.rs-3464020/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2023-12-13T15:10:53+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2023-12-11T14:15:25+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2023-12-04T13:48:10+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"353badc2-edf3-4286-a77d-6f7a5d796edd","date":"2023-12-03T13:04:24+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"7cd9bb88-9ae2-4cdf-a6cd-58247e049408","date":"2023-11-19T22:32:53+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"2ebf45ef-a60f-46c5-8d31-4e575639e6c3","date":"2023-11-08T21:37:54+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2023-10-24T19:31:00+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2023-10-20T13:11:51+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2023-10-20T13:11:24+00:00","index":"","fulltext":""},{"type":"submitted","content":"European Journal of Pediatrics","date":"2023-10-18T23:34:08+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"european-journal-of-pediatrics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ejpe","sideBox":"Learn more about [European Journal of Pediatrics](https://www.springer.com/journal/431)","snPcode":"431","submissionUrl":"https://submission.nature.com/new-submission/431/3","title":"European Journal of Pediatrics","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"8f6f5349-3a5c-4029-b0b5-fce553a2178b","owner":[],"postedDate":"October 23rd, 2023","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-02-19T15:04:19+00:00","versionOfRecord":{"articleIdentity":"rs-3464020","link":"https://doi.org/10.1007/s00431-024-05429-2","journal":{"identity":"european-journal-of-pediatrics","isVorOnly":false,"title":"European Journal of Pediatrics"},"publishedOn":"2024-02-14 15:00:58","publishedOnDateReadable":"February 14th, 2024"},"versionCreatedAt":"2023-10-23 23:36:54","video":"","vorDoi":"10.1007/s00431-024-05429-2","vorDoiUrl":"https://doi.org/10.1007/s00431-024-05429-2","workflowStages":[]},"version":"v1","identity":"rs-3464020","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3464020","identity":"rs-3464020","version":["v1"]},"buildId":"_2-kVJe1T_tPrBINL-cwx","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}