[Research progress on influencing factors of early adiposity rebound in children and the effect on adolescent development in girls].

With the increasing rate of overweight and obesity in children worldwide, adiposity rebound(AR)closely related to obesity has become the spotlight, and early AR phase has a broad impact on pubertal development in girls, but the specific mechanism of action isn't very clear.This paper is review of the prevalence of early AR at home and abroad, and its influencing factors, the impact of AR on the adolescent development of girls and related mechanisms, to identify high-risk individuals with early AR, early AR to identify early adolescent development, and take early intervention measures to promote children's health.

[Independent and combined effects of pre-pregnancy BMI and gestational diabetes on early adiposity rebound timing in children].

Objective: To examine the independent and combined effects of pre-pregnancy BMI and gestational diabetes (GDM) on early adiposity rebound (AR) timing in children. Methods: Based on the "Ma'anshan Birth Cohort Study", 2 896 eligible maternal and infant pairs were recruited. In the cohort, we collected pre-pregnancy height, weight, 24 to 28 weeks GDM diagnosis, follow-up at 42 days, three months, six months, nine months of age, and every six months after one year of age, and continuously followed up to 6 years old, and obtained the child's length/height, weight, and other data. The intensity of the association between pre-pregnancy BMI, GDM, and early AR timing was analyzed by the multivariate logistic regression model. Multiplication and additive models were used to analyze how pre-pregnancy BMI and GDM influenced early AR timing in children. Results: The prevalence of underweight, average weight, overweight, and obesity before pregnancy were 23.2% (672), 66.4% (1 923), 8.7% (251), and 1.7% (50). The prevalence of GDM was 12.4%. We found that 39.3% of children had AR, and the average age at AR was (4.38±1.08). The results of multifactorial logistic regression analysis showed that pre-pregnancy overweight (OR=1.67,95%CI:1.27-2.19), pre-pregnancy obesity (OR=3.05,95%CI:1.66-5.56), and maternal GDM (OR=1.40,95%CI:1.11-1.76) were risk factors for early AR timing in children. In contrast, pre-pregnancy underweight (OR=0.60,95%CI:0.49-0.73) was a protective factor for early AR timing in children. Compared with the different effects of pre-pregnancy overweight/obesity and maternal GDM alone, the combined effect caused a higher risk of early AR timing in children, with OR values (95%CI) were 2.03 (1.20-3.44), 3.43 (1.06-11.12), respectively. The multiplication and additive models showed no interaction between pre-pregnancy BMI and GDM-influenced early AR timing in children. Conclusion: Higher pre-pregnancy BMI and maternal GDM are the independent risk factors for the early AR timing in children, and the co-occurrence of the two is higher risks, but there was no statistical interaction.

[Studies of the norm of Karitane Parenting Confidence Scale(KPCS)among parents of infants in urban areas of China].

Objective: To establish the norm of the Chinese version of Karitane Parenting Confidence Scale (KPCS) in urban areas of China. Methods: From August to December 2017, the parents of 2 216 children (<36 months old) were selected from 15 cities (Beijing, Lianyungang, Hangzhou, Chengdu, Xi'an, Guangzhou, Changsha, Jinan, Guiyang, Ningbo, Dalian, Qinhuangdao, Maanshan, Chongqing and Wuhan) in 14 provinces by stratified random sampling. The general demographic characteristics and parents' parenting confidence were collected by a self-made questionnaire and KPCS Chinese version. The percentile norm was established. P3, P10 and P25 were used as the criteria to define the degree of lack of parenting confidence. Results: The age of mothers was (30.67±4.29). The age of the father was (32.50±4.99) years old. There were 726 (32.76%), 759 (34.25%) and 731 (32.99%) infants in 6-12, 12-23 and 24-35 months old groups. The total scores of P50, P25, P10 and P3 of KPCS (Chinese version) of infant parents in urban areas in China were 41, 38, 33, and 29 respectively. When the scores of parents were 34-37, 30-33, and ≤ 29, they were judged as mild, moderate, and severe lack of parenting confidence. There was no significant difference in the Chinese version of KPCS between parents of different age groups and parents of different gender (χ²=3.53, P=0.171; χ²=1.41, P=0.236). Each factor score≤P3 is defined as the boundary score, and the corresponding boundary scores of "parenting" "support" and "competence" were 13, 9, and 5 respectively. Conclusion: The Chinese version of KPCS can be used to assess the parenting confidence of infants in urban areas of China. It can used as one of the bases for scientific and objective evaluation of the parenting status of families.

[A cohort study of maternal pregnancy-related anxiety at different trimesters and infants' neurobehavioral development].

Objective: To investigate the influence and critical period of pregnancy-related anxiety during pregnancy on the neurobehavioral development of infants. Methods: The subjects of this study were derived from the Ma'anshan Birth Corhot. From May 2013 to September 2014, a total of 3 474 pregnant women who registered in Ma 'anshan Maternal and Child Health Care Center were enrolled in the study. A total of 2 242 mother-infant pairs who completed three times assessments of maternal anxiety and at least once assessment of infants' neurobehavioral development were included in the final analysis. Maternal pregnancy-related anxiety was assessed by the Pregnancy-Related Anxiety Questionnaire during the first, second and third trimesters of pregnancy. When their children were at 6 and 18 months, their neurobehavioral development was evaluated using the Ages & Stages Questionnaire-China. The influence of maternal pregnancy-related anxiety on the neurobehavioral development of infants was analyzed by bi-nominal logistic regression. Results: The age of 2 242 pregnant women was (26.62±3.65) years, and the proportion of boys, low birth weight and exclusive breastfeeding for 6 months was 50% (1 120/2 242), 1.7% (38/2 242) and 11.5% (252/2 191), respectively. The detection rates of pregnancy-related anxiety during the first, second and third trimester were 24.9% (558), 28.6% (642) and 30.3% (674), respectively. After controlling confounding variables and other two trimester's anxiety, only pregnancy-related anxiety during the third trimester (not first or second trimester) significantly increased the risk of developmental delay in the domain of communication (relative risk, RR = 3.52, 95% confidence interval, CI: 1.89-6.58) and personal-social (RR=2.46, 95%CI: 1.10-5.49) at the 6 months of age, as well as in the domain of fine motor (RR=2.07, 95%CI: 1.11-3.85), problem-solving domains (RR=2.31, 95%CI: 1.24-4.31). Conclusion: Maternal pregnancy-related anxiety was associated with the risk of neurobehavioral development of infants, and the third trimester may be the critical period.

[Effect of early-life antibiotic exposure on allergic symptoms in children aged 6-11 months and 18-23 months based a birth cohort study].

Objective: To analyze the associations between prenatal and 1-year-old exposure to antibiotics and allergic symptoms in children aged 6-11 months and 18-23 months. Methods: In this study, a prospective birth cohort study was adopted. A total of 2 122 pregnant women were enrolled in Maternal and Child Health Care Center of Ma'anshan from June 2015 to June 2016, and they were followed up from the beginning of pregnancy to children's 24 months of age. Excluding 564 pairs of mothers and children who were lost to follow-up or with incomplete information on the use of antibiotics and children's allergic symptoms, a total of 1 558 pairs of mothers and children were included in the analysis of this study. The parents and children's general demographic information, early-life antibiotic exposure and other data were collected, the information about allergic symptoms in children aged 6-11 months and 18-23 months were investigated by reference to the "International Study of Asthma and Allergies in Childhood (ISAAC)". The univariate and multivariate binary unconditional logistic regression model was used to was used to estimate associations between the effects of early-life antibiotic exposure on allergic symptoms in 2-year-old children. Results: The antibiotic usage rate of pregnant women during pregnancy was 3.4% (53), and the antibiotic usage rates of children between 0 to 2 months, 3 to 5 months, and 6 to 11 months were separately 15.2%(237), 15.5%(242) and 17.3%(269). The total prevalence of allergic diseases in children aged 6 to 11 months was 24.1% (375 children), and the total prevalence of allergic diseases in children aged 18 to 23 months was 22.0% (342 children). After adjust parental (maternal) education level, family monthly income per capita, parental (maternal) allergy history, parental (maternal) age at pregnancy, mother's Body Mass Index (BMI) before pregnancy, exposure to second-hand smoke during pregnancy, delivery method, child gender, birth weight, preterm birth, the use of antibiotics when children were 3-5 months old (RR=1.61,95%CI:1.19-2.17) and 6-11 months old (RR=1.43,95%CI:1.06-1.93) were the risk factors for allergic symptoms at 6-11 months of age; and the use of antibiotics when children were 0-2 months old (RR=1.41, 95%CI: 1.03-1.95), 3-5 months old (RR=1.54, 95%CI: 1.12-2.11) and 6-11 months old (RR=1.58, 95%CI: 1.17-2.14) were the risk factors for allergic symptoms at 18-23 months of age. Conclusion: Children's exposure to antibiotics within 1 year of age was a risk factor for allergic symptoms in children aged 6-11 months and 18-23 months, children should avoid unnecessary antibiotic use in infancy.

[Association of thallium exposure during pregnancy with maternal blood pressure and hypertensive disorder complicating pregnancy].

Objective: To investigate the association of thallium exposure during pregnancy with pregnant blood pressure changing and hypertensive disorder complicating pregnancy(HDCP). Methods: A total of 3 240 pregnant women who had establish maternal health care manual in Ma'anshan Maternal and Child Health-Care Hospital and met the inclusion and exclusion criteria were included in this study between May 2013 and September 2014.We collected their general demographic characteristics and blood pressure through questionnaire and medical records. Meanwhile we measured serum thallium concentrations by experimental technology. We use multiple logistic regression to analyze the association between thallium exposure during pregnancy and HDCP. Mixed linear model were used to analyze the association between thallium concentration and maternal systolic blood pressure (SBP) or diastolic blood pressure(DBP) in different trimesters Results: The age of 3 240 pregnant woman was (26.61±3.64) years, and the detection rate of HDCP was 5.9%(191).The median (P25, P75) of thallium concentrations in first trimester, second trimester and third trimester were 62.96 (50.79, 77.04), 62.19 (50.87, 75.26), 48.84 (38.00, 66.00) ng/L, respectively. Multiple logistic regression results suggested after adjusting various confounding factors, the risk of HDCP in pregnant women with high concentrations of thallium (>77.04 ng/L) in the first trimester is 1.75 (95%CI:1.01-3.03) times higher than which with low concentrations(<50.82 ng/L). Mixed linear model results suggested there are positive correlation between thallium concentrations with maternal DBP in first trimester (ß=1.12, 95%CI: 0.39-1.85). Conclusion: Exposure to high levels of thallium during first trimester may increase the risk of HDCP, and the exposure of thallium may be effective to DBP of pregnant.

[Pre-pregnancy BMI, gestational diabetes and different indicators of childhood obesity at the age of four: a prospective cohort study].

Objective: To examine the relationship between pre-pregnancy BMI, gestational diabetes (GDM) and different indicators of childhood obesity at the age of 4. Methods: Based on Ma'anshan Birth Cohort Study, singleton children who were born in Ma'anshan of Anhui province from October 2013 to April 2015, were followed for 4 years, consecutively. During the first questionnaire survey, data including pre-pregnancy weight, height and socio-demography were collected. During 24-28 week of gestation, 75 g oral glucose tolerance test was conducted for them. Childhood height, weight, waist circumference and body composition were measured at the age of 4. Comparisons between groups were performed using chi-square test, analysis of variance or t-test. The relationship between pre-pregnancy overweight/obesity, GDM and childhood obesity-related characteristics were analyzed by logistic regression model and generalized linear model analysis. Results: The prevalence rates of overweight and obesity in children at the age of 4 were 13.08% and 6.03%, respectively. After adjustment for characteristics related to mothers and their children, significantly increased risk of obesity (OR=3.27, 95%CI: 2.15-4.98), larger waist circumference (OR=2.32, 95%CI: 1.72-3.14) and higher waist-to-weight ratio (OR=2.29, 95%CI: 1.73-3.02) were seen in the offspring of women with pre-pregnancy overweight/obesity. Body composition (skeletal muscle, body fat, body fat percentage) of the offspring were strongly correlated with pre-pregnancy overweight/obesity of the mothers (P<0.05). Maternal GDM was associated with higher risk of childhood obesity (OR=1.78, 95%CI: 1.14-2.79), on mothers without GDM during pregnancy. However, neither larger waist circumference, or higher waist-to-weight ratio seemed to increase the risk. Moreover, maternal GDM was not associated with body composition measures (skeletal muscle, body fat, body fat percentage). Conclusion: Pre-pregnancy BMI and maternal GDM were independent risk factors for obesity in 4-year-old children, and pre-pregnancy BMI was correlated with various indicators of body composition in children.

[A birth cohort study of the association between prenatal serum bisphenol A concentration and infant neurobehavior development].

Objective: To explore the association between maternal bisphenol A (BPA) exposure during pregnancy and neurobehavioral development in infant. Methods: Participants were from the Ma'anshan Birth Cohort, which was established from October 2008 to October 2010 based on four municipal medical and health institutions in Ma'anshan. High-performance liquid chromatography-tandem mass spectrometry was applied for the determination of serum BPA concentration in 1 783 pregnant women sampled at their first filing, and during 2.97 to 28.1 months age of the infants. Neurobehavioral development were assessed by 0-6-year-old pediatric examination table of neuropsychological development. Generalized linear model was used to analyze the association between serum BPA levels during pregnancy and infants' neurobehavioral development. Results: A total of 931 mother-child pairs had complete data on serum BPA detection during pregnancy and assessment of infants' neurobehavioral development status. The age of pregnant women at their first filing was (26.67±3.45) years old, and the M (P25,P75) of serum BPA concentration (ng/ml) was 0.23 (0.11, 0.52), with a detection rate of 84.1% (783/931). The age of infants was (13.18±5.46) months, and 53.5% (498) were boys. The developmental quotient scores of large motor, fine motor, adaptive ability, language ability and social behaviors of infants were (97.88±16.32), (97.16±15.35), (99.64±15.47), (95.3±16.04) and (98.95±14.76) points, respectively. Generalized linear model showed that after adjusting for factors such as delivery mode, feeding mode, family per capita monthly income, preterm delivery, gender, maternal age, residence, pre-pregnancy body mass index and residence time, serum BPA level in pregnancy was negatively associated with infant's development of social behavior [ß (95%CI):-2.42 (-4.71, -0.12)]. The post-stratification analysis by infant age revealed that the serum BPA level in pregnancy was only negatively associated with the development of language and social behavior developmental quotient scores in infants between the ages of 12 and 18 months, with ß (95%CI) about -6.66 (-13.06, -0.25) and -7.401 (-12.97, -1.83), respectively. Conclusion: BPA exposure during pregnancy affects language and social behavior development in infants, and the detection window is between 12 and 18 months old of the infant.

[Association of antenatal anxiety with preterm birth and low birth weight: evidence from a birth cohort study].

Objective: To investigate the impacts of antenatal anxiety on preterm birth and low birth weight. Methods: Women in early pregnancy were recruited for follow-up, antenatal anxiety in three trimesters was screened using Self-Rating Anxiety Scale and the score ≥50 was regarded as anxiety. Logistic regression analysis was conducted to evaluate the associations of the anxiety in three trimesters, new onset anxiety in the second and third trimesters with infant birth outcomes, such as preterm birth and low birth weight. Results: The rates of anxiety in the first, second and third trimesters of pregnancy were 12.5%, 3.7%, and 7.4% respectively. We found that there was no statistical association between anxiety in the first and second trimester and preterm birth. The anxiety in the third trimester was associated with increased odds for preterm birth (OR=3.55, 95%CI: 1.62-7.82). Associations between anxiety in all three trimesters and low birth weight were not significant. New onset anxiety in the third trimester was associated with significant increased risk of premature delivery (OR=5.20, 95%CI: 1.84-14.70) and low birth weight (OR=6.93, 95%CI: 2.42-19.88). Conclusions: Our study showed that anxiety in the third trimester is an important risk factor for premature delivery, new onset anxiety symptoms in the third trimester can significantly increase the incidence of premature birth and low birth weight of infant.

[The relationship between maternal pregnancy-related anxiety and executive function in preschool children: a cohort study].

Objective: To investigate the relationship between pregnancy-related anxiety and executive function in preschool children. Methods: From October 2008 to October 2010, pregnant women and live births were enrolled in the study. The expectant pregnant women and their live singleton fetuses were recruited from the antenatal care clinic of Ma'anshan maternal and Child Health Care Hospital. The cohort was followed up from April 2014 to June 2015. A total of 3 556 pairs of maternal and child were included in the final analysis. The questionnaire was used to collect the relevant information of pregnant women and the follow-up data of children. Pregnancy-related anxiety was assessed by using the Pregnancy-Related Anxiety Questionnaire, and the executive function of preschool children was assessed by using the Behavior Rating Inventory of Executive Function-Preschool (BRIEF) (Parent Version). Bi-nominal logistic regression was used to analyze the effect of pregnancy-related anxiety on executive function in preschool children. Results: The average age of 3 556 pregnant women was (26.78±3.42) years old, and the average age of preschool children was (4.32±0.46) years old. The proportion of primipara, only child and urban children was 94.96% (3 375/3 556), 91.37% (3 249/3 556) and 88.98% (3 164/3 556), respectively. The prevalence of pregnancy-related anxiety in the 1(st) and 3(rd) trimester was 17.60% (626/3 556) and 6.30% (224/3 556) respectively. The prevalence of abnormal global executive composite was 8.54% (304/3 556). The prevalence of anxiety in both trimesters was 7.68% (273/3 556). After controlling for confounding factors such as monthly family income, education years of parents, maternal age, pre-pregnancy weight, previous adverse pregnant outcomes, number of pregnancy, pregnant complications, the main residence of the children in the past six months, and Z score of birth weight, compared with the group without pregnancy-related anxiety in either 1(st) or 3(rd) trimester, pregnancy-related anxiety in the 1(st) trimester increased the risk of preschool children's abnormality in inhibition, working memory, planning/organization and global executive composite, and the OR (95%CI) value was 1.52 (1.08-2.13), 1.41 (1.14-1.74), 1.62 (1.13-2.33), and 1.60 (1.18- 2.17), respectively. Anxiety in the 3(rd) trimester increased the risk of children's abnormality in inhibition and global executive composite, and the OR (95%CI) value was 1.90 (1.15-3.12) and 1.69(1.05-2.71). Pregnancy-related anxiety in both trimesters increased the risk of abnormality in inhibition, working memory, planning/organization, and global executive composite in preschool children, and the OR (95% CI) value was 2.41 (1.61-3.62), 2.19 (1.66-2.88), 1.80 (1.11-2.92), and 2.41 (1.65-3.52), respectively. Conclusion: The exposure to pregnancy-related anxiety during pregnancy increases the risk of executive dysfunction in preschool children.

Constraining the External Capture to the

The ^{12}C(α,γ)^{16}O reaction is one of the most crucial reactions in nuclear astrophysics. The E2 external capture to the ^{16}O ground state (GS) has not been emphasized in previous analyses but may make a significant contribution to the ^{12}C(α,γ)^{16}O cross section depending on the value of the GS asymptotic normalization coefficient (ANC). In the present work, we determine this ANC to be 337±45 fm^{-1/2} through the ^{12}C(^{11}B,^{7}Li)^{16}O reaction using a high-precision magnetic spectrograph. This sheds light on the existing large discrepancy of more than 2 orders of magnitude between the previously reported ANC values. Based on the new ANC, we experimentally constrain the GS external capture and show that through interference with the high energy tail of the 2^{+} subthreshold state, a substantial enhancement in the GS S_{E2}(300) factor can be obtained (70±7 keV b) compared to that of a recent review (45 keV b), resulting in an increase of the total S factor from 140 to 162 keV b, which is now in good agreement with the value obtained by reproducing supernova nucleosynthesis calculations with the solar-system abundances. This work emphasizes that the external capture contribution for the ground state transition cannot be neglected in future analyses of the ^{12}C(α,γ)^{16}O reaction.

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

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

MiR-188 inhibits proliferation and promotes apoptosis of lung adenocarcinoma cells by targeting SIX1 to negatively regulate ERK signaling pathway.

OBJECTIVE: To explore the effects of micro ribonucleic acid (miR)-188 on proliferation and apoptosis of lung adenocarcinoma (LUAD) cells, and its potential mechanism. MATERIALS AND METHODS: The expression level of miR-188 in LUAD cell lines was detected via quantitative Real Time-Polymerase Chain Reaction (PCR). The effects of miR-188 overexpression on proliferation and apoptosis of A549 cells were detected using methyl thiazolyl tetrazolium (MTT) assay, colony formation assay, and flow cytometry. The potential targets for miR-188 were predicted using the TargetScan Human database, and the interaction between miR-188 and target gene was determined through Dual-Luciferase reporter assay. Moreover, the associations of miR-188 and sine oculis homeobox homolog 1 (SIX1) with the extracellular signal-regulated kinase (ERK) pathway were detected via Western blotting. RESULTS: The expression of miR-188 significantly declined in LUAD cell lines (p<0.05). The overexpression of miR-188 significantly reduced the proliferation rate of A549 cells and increased the percentage of apoptotic A549 cells (p<0.05). Similarly, it was found in colony formation assay that the overexpression of miR-188 inhibited the colony formation ability of A549 cells most significantly (p<0.05). SIX1 was a direct target for miR-188, and its mRNA and protein expressions were downregulated by the overexpression of miR-188. The remarkable downregulation of phosphorylated ERK was observed in A549 cells overexpressing miR-188, while the decline in phosphorylated ERK was reversed in A549 cells overexpressing miR-188 and SIX1. CONCLUSIONS: The expression of miR-188 is downregulated in LUAD cell lines. The overexpression of miR-188 inhibits proliferation and promotes apoptosis of LUAD cells, whose functional mechanism may be related to its regulation on the ERK signaling pathway by targeting SIX1.

[Association between elective cesarean delivery and duration of breastfeeding in Ma'anshan City from 2013 to 2014].

Objective: To analyze the correlation between elective cesarean delivery and duration of breastfeeding in Ma'anshan city from 2013 to 2014. Methods: From May 2013 to September 2014, a total of 3 474 pregnant women with the first prenatal checkup were recruited from Ma'anshan maternal and child health care hospital. Finally, 3 109 pregnant women were included after exclusion of those with terminated pregnancies, adverse birth outcomes, twin or multiple pregnancies, breech traction, breech midwifery and loss of delivery information. Demographic data of pregnant women, mode of delivery and breast feeding of children were collected through questionnaires and hospital records. Logistic regression model was used to analyze the relationship between elective cesarean delivery and duration of breastfeeding in children, with the mode of delivery as independent variable and the duration of breastfeeding as dependent variable. Results: The age of 3 109 subjects was (26.6±3.6) years old, the rate of vaginal delivery was 51.1% (1 589), and the rate of elective cesarean delivery was 46.4% (1 443), among which the rate of non-indicative elective cesarean delivery was 26.4% (820), the rate of indicative elective cesarean delivery was 20.0% (623), and the rate of emergency cesarean delivery was 2.5% (77). The proportion of breastfeeding lasting until 4, 12 and 18 months was 45.0% (1 348/2 998), 23.7% (702/2 962) and 5.2% (154/2 944), respectively. After adjusting the confounding factors, compared with vaginal delivery, the OR (95%CI) values of breastfeeding for 4 months in indicative elective cesarean delivery and non-indicative elective cesarean delivery women were 0.870(0.714-1.059), 0.795(0.665-0.949), and the OR (95%CI) values of breastfeeding for 12 months were 0.772(0.611-0.975), 0.755(0.610-0.934), respectively. Conclusion: Elective cesarean delivery may result in shorter duration of breastfeeding in children.

[Practice of parenting and related factors on children aged 0-5 in the urban areas of China].

Objective: To characterize the relations between the practice of parenting and associated factors on children (0-5 years old) in urban areas of China, in order to provide evidence for promoting the early development of children and to provide positive guidance and service programs on parenting. Methods: A total of 4 515 parents from 15 cities (14 provinces) were surveyed with a self-administered questionnaire. Parenting and Family Adjustment Scales (PAFAS) was used, including parameters as: consistency and coercive parenting, positive encouragement, parent-child relationship and parental emotion adjustment, family relationship and parental teamwork aspects, etc. Both single factor analysis and multiple linear regression were used to examine the associations between parenting practice, individual, parental and family factors. Results: The mean score of PAFAS was 21.00 (15.00-28.00), associated with factors as children's age, only-child family, premature delivery, father's education level, confidence on parenting, problems regarding the parental mood, annual family income, family structure and behavior on seeking professional help, etc. Results showed that there were big differences on the practice of parenting in China and influenced by variety of factors. Conclusions: The general situation of parenting was well, in the urban areas of China. The practice of parenting was associated with a series of individual, parental and family factors. Programs on improving the parenting skills and promoting the early development of children, should be highlighted.

[Pregnancy-related anxiety associated with small-for-gestational-age infants].

Objective: To investigate the second or third trimester pregnancy-related anxiety on small-for-gestational-age infants. Methods: This study was based on Ma'anshan Birth Cohort Study (MABC), with 3 040 maternal-singleton pairs finally selected for data analysis, from May 2013 to September 2014. The psychological state of pregnancy was evaluated according to a self-developed 'anxiety scale for gestation'. Small-for-gestational-age was defined as 'having birth weight below the 10(th) percentile at a particular gestational week', while large-for-gestational-age infants was defined as 'having birth weight above the 90(th) percentile'. Birth weight between the 10(th) and 90(th) percentile was classified as appropriate-for-gestational age infants. χ(2) test was used to compare the distribution of characteristics in pregnancy among three groups with different birth weights. Multivariate logistic regression models were conducted to evaluate the associations between third trimester pregnancy- related anxiety and birth weight. Results: The incidence rates of small- and large-gestational-age infants were 9.6% and 16.6%, respectively. Difference between women with only one of the second or third trimester pregnancy-related anxiety syndromes and small-for-gestational-age infants showed no statistical significance. Women with both second and third trimester pregnancy-related anxieties might increase the risk of small-for-gestational-age infants (OR=1.39, 95%CI: 1.04-1.87). However, there was no significant difference between pregnancy-related anxiety and large-for- gestational-age infants (OR=1.05, 95%CI: 0.81-1.35) noticed. Conclusion: Women with second and third trimester pregnancy-related anxiety appeared a risk factor for small-for-gestational-age infants.

[The associations between nighttime sleep duration, bedtime and preschool children's obesity].

Objective: To examine the relationship of nighttime sleep duration and bedtime with preschool children's obesity, and to explore possible early life risk factors for childhood obesity. Methods: A total of 14 946 valid children from 16 439 pre-school children aged 3-6 years in 91 kindergartens in Ma'anshan city participated in the study. The body mass index cut-offs for overweight and obesity in Chinese children and adolescents aged 2-18 years was used as the criterion for judging overweight and obesity, and pathological and secondary causes of obesity were excluded. The associations of nighttime sleep duration and bedtime with preschool children's obesity was analyzed by using non-conditional multivariate binary logistic regression model. Results: Among the preschool children, 22.4% (n=3 345) had shorter sleep duration. 9.5% (n=1 415) had bedtimes after 22:00 on weekdays and 21.8% (n=3 260) had bedtimes after 22:00 on weekends. The prevalence of overweight and obesity were 16.5% (n=2 466) and 10.5% (n=1 562), respectively. After the adjustent of age, gender, whether or not only child, residence in the last six months, parents' body mass index parents' educational level, diet preference, outdoor activities, TV viewing duration, sleep duration, bedtime on weekdays and weekends, only the shorter sleep duration (OR=1.25, 95%CI: 1.03-1.51) was still positively associated with the prevalence of obesity in preschool children. Conclusion: Shorter sleep duration was positively associated with the prevalence of obesity among preschool children.

[The relationship of maternal and umbilical cord blood zinc level associated with newborn birth weight: a birth cohort study].

Objective: To study serum zinc level in pregnancy and umbilical cord blood and their association with newborn birth weight. Methods: Pregnant women accepting obstetric examination in Ma'anshan Maternal and Child Care Center were recruited from May 2013 to September 2014. The follow up was conducted during their first, second and third trimesters of pregnancy and the self-designed questionnaire was used to collect information of social and demographic characteristics. Blood samples in the first, second pregnancy period and umbilical cord blood samples were collected and serum concentrations of zinc were assayed. 3 239 mother-infant entered the final analysis. We divided serum zinc level into low (P(75)) groups according to their exposure concentrations at each trimesters. Non-conditional multivariate logistic regression model was conducted to evaluate the association between serum zinc level in first, second trimesters of pregnancy and umbilical cord blood with small for gestational age (SGA) and large for gestational age (LGA). Results: Serum zinc level in P(50) (P(25)-P(75)) during the first, second trimesters and cord blood were 1 016.18 (907.09-1 145.60), 813.36 (732.47-897.89) and 903.44 (808.71-1 015.64) µg/L, respectively. The prevalence of zinc deficiency during the first, second trimesters and cord blood were 1.5% (44/2 957), 15.9% (492/3 087) and 6.5% (176/2 707), respectively. The prevalence of total SGA and LGA were 9.7% (313/3 239) and 16.5% (536/3 239), respectively. Compared to high-level serum zinc group, the risk of SGA (OR (95%CI) in low-level serum zinc group during first trimesters was 1.51 (1.05-2.19)). Serum zinc level among second pregnancy period and umbilical cord blood had no statistically significant effect on SGA and LGA (both P values >0.05). Conclusion: Zinc nutritional status of pregnant women in Ma'anshan city was at a good level. The low serum zinc level in first trimester increased the risk of SGA.

[Association between early pregnancy bisphenol A exposure and sleep problems among preschool children].

Objective: To analyze the association between maternal bisphenol A exposure during early pregnancy and sleep problems among preschool children. Methods: Research subjects were from one of the sub-cohorts(Ma'anshan Cohort) of the China-Anhui Birth Cohort Study (C-ABCS) in Ma'anshan city. The basic situation of pregnant women and sleep information of preschool children were investigated. We selected preschool children whose mother's maternal serum bisphenol A concentrations of the first trimester had been already detected between December 2012 to Januray 2014. 1 259 pairs of mothers and children were included. The concentrations of bisphenol A exposure during early pregnancy were divided into low, medium and high exposure groups according to 25(th) percentile (P(25)) and 75(th) percentile (P(75)) levels. Multivariate multinomial logistic regression model was used to analyze the association between maternal bisphenol A exposure during early pregnancy and sleep-related problems in preschool children. Results: The P(50) (P(25)-P(75)) of serum bisphenol A exposure level during early pregnancy was 0.231 (0.106-0.512) ng/ml. The sleep-related problems scores of 1 259 preschool children were (16.43±3.82) points. The occasional sleep-related problems were detected about 47.8% (602 cases) and frequent sleep-related problems were detected about 18.3% (230 cases). After the adjustment of the confounding factors such as children's gender, age, BMI, sleep position (lying down, sleeping on one's back), the length of time to sleep and the length of sleep at night, in comparison with bisphenol A low exposure group, the OR (95%CI) value of preschool children with occasional sleep-related problems in maternal bisphenol A high exposure group during early pregnancy was 1.44 (1.01-2.06). After the gender stratification, the results showed that in comparison with bisphenol A low exposure group, the OR (95%CI) value of preschool girls with occasional sleep-related problems in maternal bisphenol A medium and high exposure group during early pregnancy were 1.61 (1.05-2.46) and 2.40 (1.42-4.04), respectively. The OR (95%CI) value of preschool girls with frequent sleep-related problems in maternal bisphenol A high exposure group during early pregnancy was 2.64 (1.34-5.17). However, in boys, there was no statistically significant association between maternal bisphenol A exposure during early pregnancy and sleep-related problems (P>0.05). Conclusion: Maternal bisphenol A exposure during early pregnancy might be related to sleep-related problems in preschool children.

[Developmental characteristics of circadian rhythms in hypothalamic-pituitary-adrenal axis during puberty].

Objective: To explore the developmental characteristics of circadian rhythms in hypothalamus-pituitary-adrenal (HPA) axis during puberty. Methods: A total of 1 070 students from Grade 2-3 in 3 primary schools in Ma'anshan city, Anhui province, were selected for physical examination and circadian rhythm of HPA axis checked from 2015 to 2017. Saliva samples were collected at each of the following three time points: immediately upon wakening, 30 minutes after wakening and bedtime, with the index of circadian rhythm of HPA axis calculated, which including cortisol awake response (CAR), cortisol in puberty priming and diurnal cortisol slope (DCS). Testicular volume, palpation and visual inspection of breast development were used to assess the state of purbety development on boys and girls. Information on gender, date of birth, time to fall asleep, wake-up time and weekly physical activity were gathered through questionnaire survey. Non-parametric test was used to compare the differences of baseline, follow-up period and different adolescent developmental processes of each index on circadian rhythm of HPA axis. Results: During the period of follow-up program and comparing with the continuous undeveloped group, CAR and the changes of CAR showed significantly increase, both in the puberty priming group and continuous development group, with statistically significant differences (CAR: Z=8.551, 4.680, respectively; P<0.01; the changes of CAR: Z=4.079, 2.700, respectively, P<0.01). There were no significant differences noticed in CAR and the changes of CAR between puberty priming group or continuous development group. The area under the curve (AUC) of cortisol in puberty priming group was slightly higher than that in the persistent undeveloped group (Z=2.591, P=0.010). Both the changes of daily cortisol slope (DCS) in puberty priming group and continuing developed group decreased significantly, when comparing with those in continuous undeveloped group (Z=-2.450, Z=-2.151; all P<0.05). There was no significant difference noticed in the changes of cortisol in puberty priming and DCS between different puberty development stages (the changes of AUC: χ(2)=2.747, P=0.253; DCS: χ(2)=4.554, P=0.032). Conclusions: The indexes of circadian rhythm of HPA axis were associated with the development of puberty. Both the cortisol awakening response and the total amount of diurnal cortisol secretion showed an increase, along with the puberty development. The change of diurnal cortisol slope declined with the development of puberty.