[Prevalence of and risk factors for perceived absence of breast milk supply in Chinese lactating women in 2013].

OBJECTIVE: To investigate the prevalence and influencing factors of postpartum perceived absence of breast milk supply among Chinese mothers in 2013. METHODS: This is a cross-sectional study based on the data collected from children and mothers under 2 years of age in 2013 as part of the nutrition and health surveillance of Chinese residents. In this study, multistage stratified cluster sampling method was used to select subjects from 55 countires/districts in 30 provinces in China. The perceived absence of breast milk supply was defined as the mother's self-reported absence of breast milk and failure to breastfeed. Breastfeeding knowledge, maternal breastfeeding knowledge and general characteristics were collected through a structured questionnaire. Univariate analysis and Logistic regression were used to analyze the factors associated with perceived absence of breast milk supply. RESULTS: A total of 12091 mothers were included in the study, including 419 in the perceived non-breastfeeding group, the prevalence of perceived absence of breast milk supply was 3.5%. Multivariate Logistic regression showed maternal age(OR=1.04, 95%CI 1.02-1.06), postpartum hemorrhage(OR=2.03, 95%CI 1.30-3.16), and belief that breastfeeding should continue beyond 12 months of age(OR=0.27, 95%CI 0.17-0.45), not knowing how to breastfeed(OR=3.31, 95%CI: 2.31-4.74) were the main influencing factors for perceived absence of breast milk supply after delivery. CONCLUSION: Age, postpartum hemorrhage and knowledge level of breastfeeding are the main risk factors for perceived absence of breast milk supply, and knowledge level of breastfeeding is a modifiable factor.

[Energy and nutrients intake from complementary foods of children aged 6-23 months in China in 2019-2021].

OBJECTIVE: To describe the energy and nutrients intake from complementary foods of children aged 6-23 months in different areas of China. METHODS: The data was from the National Special Program for Science & Technology Basic Resources Investigation-China Children's Nutrition and Health System Survey and Application of 0-18 Years Old Children. Children aged 6-23 months(n=546) were included in the current study. Demographic characteristics, socioeconomic status and birth status were collected through questionnaire survey. We used 24-hour weighted dietary record method to collect the intake of complementary foods. Energy, protein, fat, carbohydrate, calcium, iron, zinc, selenium, potassium, vitamin A, vitamin B_1, vitamin B_2 and vitamin C intakes were calculated by using Chinese Food Composition Database. RESULTS: For children aged 6-8 months, 9-11 months, 12-17 months and 18-23 months, the energy intake from complementary foods was 156.1, 258.0, 388.7 and 581.1 kcal, respectively. The protein intake was 5.1, 10.1, 15.0 and 21.7 g, respectively. The fat intake was 3.3, 6.7, 9.5 and 15.9 g, respectively. The calcium intake was 38.7, 54.8, 78.6 and 106.9 mg, respectively. The iron intake was 1.3, 2.2, 3.5 and 5.3 mg, respectively. The zinc intake was 0.7, 1.4, 2.0 and 2.9 mg, respectively. The vitamin A intake was 83.7, 100.3, 157.4 and 180.4 µgRAE, respectively. The vitamin B_1 intake was 0.1, 0.2, 0.2 and 0.3 mg, respectively. The vitamin B_2 intake was 0.1, 0.1, 0.2 and 0.3 mg, respectively. The vitamin C intake was 1.8, 6.3, 9.5 and 19.2 mg, respectively. Compared with the World Health Organization recommended value of nutrients density, the density of protein from complementary foods for children aged 6-23 months was higher(2.6-3.8 mg/100 kcal vs.0.9-1.0 mg/100 kcal). The density of iron(1.0, 0.9 mg/100 kcal vs.4.5, 3.0 mg/100 kcal) and zinc(0.5, 0.5 mg/100 kcal vs.1.6, 1.1 mg/100 kcal) was lower for children aged 6-8 months and 9-11 months, respectively. CONCLUSION: The main issues of complementary food for children in China were high protein for children aged 6-23 months and low iron and zinc for infants aged 6-11 months.

[Status of infant and young child feeding in China in 2016-2017].

OBJECTIVE: To describe the feeding status and related factors of infant and young child aged 6-23 months in China. METHODS: Data was from the China Nutrition and Health Surveillance among 0-17 Years Old Children and Lactating Women in 2016-2017, and 20 423 children aged 6-23 months were involved in 275 surveillance sites from 31 provinces(autonomous regions and municipalities). The introduction of solid, semi-solid or soft foods, minimum dietary diversity, minimum meal frequency were analyzed with WHO and UNICEF 2021 updated infant and young child feeding indicators. Data analyses were conducted using the complex weight based on national census from National Bureau of Statistics in 2010. Rao-Scott Chi-square was used test for statistical difference. RESULTS: The percentage of infants 6-8 months of age who consumed solid, semi-solid or soft foods was 83.2%(95%CI 80.5%-85.9%) in 2016-2017. No significant difference were observed between boys and girls; there was significant difference in different areas(Rao-Scott χ~2=30.85, P<0.01), it was 90.3% in medium and small cities, and reached 75.0% even in poor rural areas. The proportions of children aged 6-23 months meeting minimum dietary diversity(MDD) was 60.6%(95%CI 58.1%-63.1%). It was 71.1% in medium and small cities, and 50.5% in poor rural areas. Except for breast milk, the percentage of eggs(34.4%) and legumes(19.0%) consumption was low, the percentage of grains, vitamin A-rich fruits or vegetables consumption was 89.7%(95%CI 88.4%-91.1%). The percentage of consuming egg and/or flesh food was 76.4%(95%CI 74.2%-78.7%). The percentage of zero vegetables or fruits consumption was 9.1%(95%CI 7.8%-10.4%). The proportions of children aged 6-23 months meeting minimum meal frequency(MMF) was 72.4%(95%CI 70.1%-74.7%). It was over 70% in large cities, medium and small cities, general rural areas; and 60.2% in poor rural areas. The proportions of children aged 6-23 months meeting minimum acceptable diet was 43.4%(95%CI 40.7%-46.1%), it was over 50% in urban areas, and less than 40% in rural areas, 30.1% in poor rural areas. No consistent differences were observed between boys and girls for all 3 indicators(MDD, MMF and MAD), and there was significant difference in different areas and various months of age(P<0.01). CONCLUSION: There was no gender difference in the feeding status of children aged 6-23 months in China, the complementary feeding was relatively timely, and the minimum dietary diversity and meal frequency of children were relatively ideal, but the minimum acceptable diet of children in poor rural areas was poor.

[Breast milk intake of Chinese infants aged 0-5 months in 2019-2021].

OBJECTIVE: To describe the breast milk intake of infants aged 0-5 months in China and its trends, and to analyze the effects of feeding mode, gender and regions on breast milk intake. METHODS: Data were extracted from Ministry of Science and Technology's basic resource survey project "China's 0-18-year-old children's nutrition and health system survey and application" project. Caregivers were face to face interviewed to collect the basic information of infants. Weighing method was used to measure 24 hourly breast milk intake of infants aged 0-5 months in China. The rank sum test was used to compare the differences in breast milk intake between groups, the Spearman rank sum test was used to analyze the trend of breast milk intake with increasing age, and the general linear regression model was used to analyze the effects of gender and region on breast milk intake. RESULTS: The mean breast milk intake of exclusively breastfed infants aged 0-5 months was 800.1 g/d, ranging from 696.4 to 937.7 g/d. Breast milk intake increased with age and remained stable at 5 months(ß=29.6, P=0.009). There was a statistically significant difference in breast milk intake among infants in different month age groups(χ~2=17.96, P=0.003). Infants aged 0-5 months who are exclusively breastfed were fed 8 times in 24 hours, the breast milk intake per each time is 103.4-152.5 g, the duration of each feeding is 20.4-24.6 min, and the breast milk intake per minute is 4.4-7.0 g. Except for 5 months of age, there was no gender difference in the 24-hour breast milk intake of exclusively breastfed infants aged 0 to 4 months(P>0.05). Except for 4-month-old exclusively breastfed infants, there was no regional differences in the breast milk intake of others(t=-4.25, P<0.001). In the mixed feeding group, breast milk + complementary feeding group and breast milk + formula powder + complementary feeding group, the breast milk intake of infants aged 0-5 months were 341.1-496.7 g, 239.1-742.7 g and 90.0-508.0 g, respectively. CONCLUSION: In 2019-2021, infants aged 0-5 months in China Breast milk intake increased with age, and remained stable at 5 months. The breast milk intake of infants aged 0-5 months in different regions or genders is similar except for individual months. The introduction of formula or complementary food directly affects the intake of breast milk in infants.

[Dietary micronutrient intake of children aged 2-5 years in China in 2019-2021].

OBJECTIVE: To describe dietary intake of calcium, iron, zinc, selenium, vitamin A, vitamin B_1, vitamin B_2 and vitamin C and compare the intake between urban and rural areas among preschool children aged 2-5 years based on the data from the National Nutrition and Health Systematic Survey for Children 0-17 Years of Age in China. METHODS: Children from 14 provinces were selected by multi-stage stratified random cluster sampling, and the dietary data of preschool children aged 2-5 years were recorded using the 3 day 24-hour weighted food records method. SAS 9.4 was used to calculate dietary intake of these micronutrients based on the Chinese Food Composition Table and to compare the intake between urban and rural areas. The risk of insufficient or excessive intake of micronutrients among Chinese children aged 2-5 years was assessed according to the Chinese Dietary Reference Intakes(DRIs) 2013 edition. RESULTS: A total of 820 children aged 2 to 5 years were selected. The median daily dietary calcium intake of children aged 2-5 years in China was 433.7, 338.9, 356.4 and 347.4 mg, respectively. The median daily dietary intake of vitamin B_1 of children aged 2-5 years was 0.5 mg for all age groups. The median daily dietary vitamin B_2 intake of children aged 2-5 years was 0.7, 0.6, 0.6 and 0.6 mg, respectively. The median daily dietary intake of vitamin C of children aged 2-5 years was 37.9, 37.4, 44.0 and 40.0 mg, respectively. The median daily dietary selenium intake of children aged 2-5 years was 17.1, 20.5, 22.7 and 22.3 µg, respectively. Dietary calcium intake for aged 2-5 years, dietary vitamin B_2 intake for aged 2-4 years, dietary iron, selenium, zinc and vitamin B_1 intake for aged 2-3 years was significantly greater in urban children than rural children. Among all nutrients, the proportion of dietary calcium intakes below the estimated average requirement(EAR) was the highest in aged 2-5 years(61.4%, 76.4%, 91.4% and 91.5%, respectively). The proportions of dietary vitamin B_1, vitamin C and selenium intake lower than EAR of children aged 2-5 years in China were 52.4%-63.2%, 42.8%-50.2% and 46.6%-58.7%, respectively. COUCLUSION: The dietary calcium intake of children aged 2-5 years in China remains insufficient for these children, especially for rural children. Dietary vitamin B_1, vitamin C and selenium intake should be improved.

Human milk cholesterol is associated with lactation stage and maternal plasma cholesterol in Chinese populations.

BACKGROUND: Milk cholesterol concentrations throughout lactation were analyzed, and the relationship between maternal plasma cholesterol and milk cholesterol in various Chinese populations was examined. METHODS: A sub-sample of 1138 lactating women was randomly selected from a large cross-sectional study in China (n = 6481). Milk cholesterol concentrations were determined by HPLC, and concentrations of maternal plasma lipids were determined by an automated biochemical analyzer. RESULTS: The mean cholesterol concentrations were 200, 171, and 126 mg/L for colostrum, transitional milk, and mature milk, respectively. Cholesterol concentrations differed significantly between stages of lactation (colostrum vs. transitional milk, colostrum vs. mature milk, transitional milk vs. mature milk, all p < 0.001). Concentrations of maternal plasma total cholesterol (TC) (p = 0.02) and low-density lipoprotein cholesterol (LDL-C) (p = 0.03) were significantly associated with milk cholesterol. Milk cholesterol concentrations varied among different ethnicities (Tibetan vs. Hui: 164 vs. 131 mg/L, p = 0.027) but not among different geographic regions. CONCLUSIONS: The concentration of cholesterol in human milk changes dynamically throughout lactation. Milk cholesterol concentrations are significantly associated with maternal plasma concentrations of TC and LDL-C, and milk cholesterol concentrations vary across ethnicities in China. IMPACT: Concentrations of milk cholesterol were measured in various Chinese populations. Cholesterol concentrations differ significantly between stages of lactation. Maternal plasma total cholesterol and low-density lipoprotein cholesterol are associated with milk cholesterol. Milk cholesterol concentrations vary across ethnicities in China.

What are the determinants of low exclusive breastfeeding prevalence in China? A cross-sectional study.

Exclusive breastfeeding (EBF) status is far from the national target in China. To identify the modifiable factors associated with EBF of infants aged under 6 months in China. A cross-sectional study was conducted in 12 provinces/municipalities across China in 2017-2018. We used multistage stratified cluster sampling and collected data through face-to-face interviews with mothers using an electronic questionnaire. Totally, 5287 pairs of mother-infant aged <6 months were investigated. The EBF prevalence was 29.2% (1544/5287). Mothers with correct knowledge of colostrum (adjusted odds ratio [AOR]:1.32, 95% confidence interval [CI]: 1.07, 1.62), EBF (AOR: 1.39, 95% CI: 1.06, 1.81) and the highest scores of perceptions for breastfeeding benefits (AOR: 1.36, 95% CI: 1.14, 1.61) were more likely to exclusively breastfeed. However, mothers with more frequent unwillingness of breastfeeding during the first month postpartum were less likely to practice EBF (AOR: 0.68, 95% CI: 0.52, 0.90). Infants having their first breast milk within 24 h of birth increased the odds of EBF (AOR: 2.41, 95% CI: 1.86, 3.13). Infants were less likely to be exclusively breastfed in the families in which the main caregiver was the grandmothers. Mothers without receiving infant formula feeding suggestions via the health facilities, media, or the Internet (AOR: 1.57, 95% CI: 1.33, 1.85) or without the experience of infant formula feeding in public (AOR: 1.45, 95% CI: 1.23, 1.72) might more likely to practice EBF. To acquire comprehensively correct knowledge and keep a positive attitude of breastfeeding for the mothers are crucial for improving the EBF prevalence. Family supports are potential interventions worth focusing on. Infant formula promotion remains a great barrier for EBF in China.

[Gestational weight gain and associated factors of Chinese women in the second and third trimester of pregnancy in 2015].

OBJECTIVE: To describe gestational weight gain status of pregnant women in China, and to explore potential factors related to gestational weight gain of pregnant women in the 2 nd and 3 rd trimester in 2015. METHODS: Participants were from Chinese National Nutrition and Health Surveillance in 2012 and in 2015. Using a multi-stage stratified cluster random sampling method, a total of 8512 pregnant women were recruited in 2015. A standard questionnaire was used to collect general information and pre-pregnancy weight. Body weight and height of pregnant women were measured using a unified weighing scale and stadiometer. RESULTS: In 2015, the prevalences of underweight, normal weight, overweight and obesity in pre-pregnancy were 16.0%, 66.0%, 14.9%, 3.1% according to Chinese BMI standard, respectively. In the 2 nd trimester, the prevalences of inadequate gestational weight gain, appropriate gestational weight gain and excess gestational weight gain were 14.6%, 27.2% and 58.2% based on IOM gestational weight gain standard, respectively. In the 3 rd trimester, the prevalences of inadequate gestational weight gain, appropriate gestational weight gain and excess gestational weight gain were 12.7%, 31.5%, 55.8% based on IOM gestational weight gain standard, respectively. The odds of excess gestational weight gain was 1.53(95%CI 1.19-1.99) in the second trimester, and 2.05(95% CI 1.59-2.63) in the third trimester for overweight women, compared to normal weight women during pre-pregnancy. The prevalence of excess gestational weight gain showed an increasing trend in both urban and rural areas, which was not related to pregnant women's age and education. Second parity might be a protective factor for appropriate weight gain in late pregnancy. CONCLUSION: Compared to 2012, the prevalence of underweight before pregnancy and inadequate gestaional weight gain decreased in 2015. By contrast, the prevalence of overweight, obesity and excess gestational weight gain showed an upward trend.

Low selenium intake is associated with postpartum weight retention in Chinese women and impaired physical development of their offspring.

The aim of this study was to investigate the association between daily Se intake and postpartum weight retention (PPWR) among Chinese lactating women, and the impact of their Se nutritional status on infants' physical development. Se contents in breast milk and plasma collected from 264 lactating Chinese women at the 42nd day postpartum were analysed with inductively coupled plasma MS. Daily Se intake was calculated based on plasma Se concentration. The dietary data of 24-h records on three consecutive days were collected. Infant growth status was evaluated with WHO standards by Z-scores. Linear regression analyses and multinomial logistic regression were conducted to examine the impact of Se disequilibrium (including other factors) on PPWR and growth of infants, respectively. The results indicated that: (1) the daily Se intake of the subjects was negatively associated with their PPWR (B = -0·002, 95 % CI - 0·003, 0·000, P = 0·039); (2) both insufficient Se daily intake (B = -0·001, OR 0·999, 95 % CI 0·998, 1·000, P = 0·014) and low level of Se in milk (B = -0·025, OR 0·975, 95 % CI 0·951, 0·999, P = 0·021) had potential associations with their infants' wasting, and low level of Se in milk (B = -0·159, OR 0·853, 95 % CI 0·743, 0·980, P = 0·024) had a significant association with their infants' overweight. In conclusion, the insufficient Se nutritional status of lactating Chinese women was first found as one possible influencing factor of their PPWR as well as low physical development of their offspring.

[Association between timing for introducing complementary foods and body composition of children aged 3-5 years in five provinces of China].

OBJECTIVE: To explore the association between different timing of introducing complementary foods during infancy and the body composition of children aged 3-5 years. METHODS: The data was from National Nutrition and Health Systematic Survey for 0-18 Years Old Children in China. A face-to-face interview to caregivers of children was conducted to retrospectively collect timing of introducing complementary foods of children aged 3-5 years. The bioelectrical impedance analysis was used to measure the body composition of children by professionally trained investigators. The exposure variable of the study was the timing of introducing complementary foods(≤5 months old, 6 months old and ≥7 months old). The outcome variables were the fat-free mass, fat-free mass index, body fat mass, body fat mass index, and percentage of body fat. According to age stratification, a multivariate linear regression model was used to calculate the mean, mean difference and 95% CI after adjusting for potential confounders. RESULTS: After adjusting for potential confounders, there were no statistically significant difference in body fat mass, body fat mass index, percentage of body fat and fat-free mass index among different groups of timing for introducing complementary foods for children aged 3-5 years old. For children aged 3-5 years, after adjusting for potential confounders, the difference of fat free mass was statistically significant among children with different timing for introducing of complementary foods(3 years old: 12.89 kg vs. 12.66 kg vs. 12.94 kg, F=4.42, P=0.013; 5 years old: 16.27 kg vs. 16.23 kg vs. 16.66 kg, F=5.40, P=0.005). The fat free mass of children aged 3 years was lower when introducing complementary foods during 6 months of age than at ≤5 months of age(mean difference=-0.23 kg(95% CI-0.45--0.02 kg)). The fat free mass of children aged 5 years was higher when introducing complementary foods at ≥7 months of age than at≤5 months of age(mean difference=0.39 kg(95% CI 0.08-0.70 kg)). CONCLUSION: It is found that the association between timing for introducing complementary foods during infancy and the fat mass indicators of children aged 3 to 5 years was not statistically significant, and the association between timing for introducing complementary foods and fat-free mass may be inconsistent for different fat-free mass indicators.

[Relationship between dietary behavior and malnutrition of children aged 3-5 years in five cities of China].

OBJECTIVE: To explore the status of malnutrition and dietary behavior characteristics of children aged 3-5 in Tonghua, Nanchang, Changsha, Kunming and Weinan, and to analyze the relationship between them. METHODS: Data was from National Nutrition and Health Systematic Survey for 0-18 Years Old Children in China. A total of 1741 children were randomly selected from five cities by multi-stage stratified cluster sampling, and their physical fitness was measured and investigated by questionnaire. Chi-square test and multivariate binomial Logistic regression analysis were used to assess the relationship between nutritional deficiency and diet and feeding behavior. RESULTS: Among the investigated children, the underweight rate, stunting rate and wasting rate were 0.52%, 1.09% and 1.03%, respectively. Dietary behavior restriction was the risk factor for stunting(OR=4.72, 95% CI 1.41-15.84), poor eating habits were the risk factor for wasting(OR=3.64, 95% CI 1.01-13.34). No statistical association was found between underweight and diet and feeding behavior. CONCLUSION: The incidence of malnutrition among children aged 3-5 years in five urban areas of China is low. There is a correlation between malnutrition and poor diet and feeding behavior. Measures should be taken to correct the poor eating habits of children and the feeding behavior of caregivers, so as to improve the nutritional status of children.

[Development and validation of children physical activity questionnaire].

OBJECTIVE: To develop the physical activity questionnaire for Chinese children aged 6-17 years old, in order to evaluate the children's physical activity. METHODS: After systematic review, expert review and preliminary investigation, the "6-to 17-year-old Chinese children physical activity questionnaire(CCPAQ)" was established to measure the weekly physical activity. Based on the sample size estimation and inclusion and exclusion criteria, 120 children aged 6-17 were selected from one survey site in the south and north of China. SAS 9.4 software and Mplus 8.0 software were used for factor analyses to validate the modes and types of physical activity measured by CCPAQ. RESULTS: This study included 119 subjects in total. Exploratory factor analyses were used to assess the 33 modes and 7 types of physical activity time and extract four and one common factor, respectively. Confirmatory factor analysis fitted a second-order 4 factors model and first-order 7 factors model. The evaluation index of the two models were χ~2/df=1.41 and χ~2/df=1.61, respectively, showing that the models fitting were acceptable. CONCLUSION: CCPAQ established in this study can effectively measure the physical activity of Chinese children aged 6-17 years.

[Association between timing of introducing complementary foods and anemia of infants aged 6-11 months in four provinces of China].

OBJECTIVE: To analyze the anemia status of infants aged 6-11 months in Beijing, Shanxi, Jiangxi and Zhejiang of China, and to explore the association between timing of introducing complementary foods and hemoglobin level, anemia of infants aged 6-11 months. METHODS: Data was from National Nutrition and Health Systematic Survey for 0-18 Years Old Children in China. A total of 1404 infants aged 6-11 months from Beijing, Shanxi, Jiangxi and Zhejiang were enrolled in this study. Demographic characteristics, socioeconomic status, birth status and complementary feeding information were collected through questionnaire survey. HemoCue Hb201+ hemoglobin analyzer was used to measure hemoglobin value. The exposure variables in this study were timing of introducing complementary foods(≤5 months, 6 months and ≥7 months), and the outcome variables were hemoglobin level and anemia rate. The association between timing of introducing complementary foods and hemoglobin level was analyzed by using multivariate linear regression model, and the association between timing of introducing complementary foods and anemia rate was analyzed by using multivariate Logistic regression model. RESULTS: The hemoglobin levels of infants aged 6-11 months were(114.8±11.0)g/L, (115.5±10.5)g/L in urban areas and(114.1±11.5) g/L in rural areas. The anemia rate was 28.2%, 24.0% in urban areas and 32.9% in rural areas. The hemoglobin levels of infants introducing complementary foods at ≤5 months, 6 months and ≥7 months were(114.0±11.1), (115.2±10.9) and(114.5±10.7) g/L, respectively. After adjusting for potential confounding factors, there was no significant difference in hemoglobin level between the ≤5 months group and 6 months group(F=2.37, P=0.124), and no significant difference between the ≥ 7 months group and the 6 months group(F=0.09, P=0.770). The anemia rate of infants introducing complementary foods at ≤5 months, 6 months and ≥7 months were 32.3%, 27.9% and 22.7%, respectively. After adjusting for potential confounding factors, there was no significant difference in anemia rate between the ≤5 months group and 6 months group(OR=1.26(95%CI 0.86-1.83)), and no significant difference between the ≥7 months group and the 6 months group(OR=0.65(95%CI 0.35-1.20)). CONCLUSION: Anemia remains a serious problem for infants aged 6-11 months in Beijing, Shanxi, Jiangxi and Zhejiang. Timing of introducing complementary foods may not be related with hemoglobin level and anemia rate of infants aged 6-11 months.

[Prevalence and risk factors for anemia of Chinese lactating women in 2013].

OBJECTIVE: To investigate the prevalence of anemia and its risk factors for lactating women in China. METHODS: Data was extracted from Chinese National Nutrition and Health Surveillance-Mothers for children under 2 years of age(2013). Totally, 11 178 mothers of children under 2 years old were selected from 55 counties of 30 provinces in China by using the multi-stage stratified cluster randomization sampling method. Among these women 7129 are lactating. The basic information of lactating women was collected through the questionnaire survey. Hemoglobin concentration was measured by photometric determination of haemiglobincyanide(HiCN) method. Participants without blood sample and basic information were excluded. Finally, 6255 lactating women were included in the analysis. Complex sampling method with weighted analysis was used. RESULTS: Totally, with a complex sampling method with weighted analysis, the prevalence of anemia for lactating women was 9.3%. The mean hemoglobin level was(136.1±0.9) g/L. The mild and moderate anemia accounted for 98.8% of all anemic cases. Compared with those lactating time<6 months, lactating time between 6 to 12 months had a lower risk of anemia(OR=0.74, 95%CI 0.61-0.90). Compared with those living in large cities, the maternal living in poor rural areas had a higher risk of anemia(OR=1.69, 95%CI 1.29-2.20). CONCLUSION: In 2013, the prevalence of anemia was mild for the lactating women in China. Lactating women in poor rural areas, within 6 months after deliveryhad the higher risk for anemia.

[Nutritional status of vitamin B_(12) and its influence factors in Chinese lactating women in 2013].

OBJECTIVE: To examine the vitamin B_(12) status of lactating women in China and to analyze the factors affecting the level of serum vitamin B_(12) in these subjects. METHODS: Participants were from the Chinese National Nutrition and Health Surveillance in 2013. By multi-stage stratified cluster randomly sampling method, 10 331 lactating women were selected from 55 counties of 30 provinces in China. Questionnaire was conducted to collect the basic information of lactating women and the dietary intake of them in the past one month was collected by food frequency questionnaire. A total of 20% of the total number of lactating women(a total of 1976) were randomly selected to analyze serum vitamin B_(12) by electro-chemiluminescence immunoassay method. Serum vitamin B_(12) deficiency was defined as a serum vitamin B_(12) level<200 pg/mL. The distribution of serum vitamin B_(12 )was lognormal, a generalized linear model was used to analyze the factors affecting the serum vitamin B_(12) level after logarithm transformation of it. RESULTS: The median of serum vitamin B_(12)(P25, P75) in lactating women was 469. 0(349. 0, 633. 5)pg/mL, the prevalence of vitaminB_(12) deficiency was 2. 7%(53/1976)and marginal deficiency rate was 12. 8%. With the increase of the education level of the lactating women the rate of vitamin B_(12) deficiency decreased gradually. The rate of vitamin B_(12 )deficiency of the lactating women presented regional differences and varied significantly among different regionals, education levels and the mothers who were breastfeeding or not. The value of serum vitamin B_(12 )was analyzed by generalized linear regression model showed that the levels of serum vitamin B_(12) in general rural counties and medium-sized or small cities were 1. 07 and 1. 13 times higher than those in poor rural areas, respectively. The serum vitamin B_(12) level of non-lactating women was 1. 08 times higher than that of lactating women. The serum vitamin B_(12 )level of the lactating women with junior high school level or below was significantly lower than that of the lactating women with college education and university education level, 88. 3% and 85. 0% of the lactating women with college education and university education, respectively. Serum vitamin B_(12) levels were positively correlated with intake of livestock meat, fish and seafood. CONCLUSION: The status of vitamin B_(12) in lactating women in China is good. Our findings suggest that some regionals, education levels, breastfeeding or not and livestock meat, fish meat and seafood supplement may be associated with serum vitamin B_(12 )in lactating women.

[Relationship between household safe drinking water, hygienic toilet and prevalence of stunting for Chinese children aged 0 to 5 years old in 2013].

OBJECTIVE: To investigate the relationship between household drinking water, toilet status and the prevalence of stunting for Chinese children aged 0 to 5 years old in 2013. METHODS: Data was extracted from the Chinese National Nutrition and Health Surveillance in 2013. A total of 32 861 children aged 0 to 5 years old were selected from 165 townships(streets) of 55 counties(cities/districts) in 30 provinces. Caregivers were face to face interviewed to collect data, including demographic characteristics of children, mothers and household, main source of household drinking water and main type of household toilet. Height/Length of children was measured using a standard procedure. Height(Length) for age Z score(HAZ(LAZ)) was calculated using WHO Anthro Survey Analyser software(online version), and stunting was defined as HAZ(LAZ)<-2. SAS 9. 4 was used to analyze. SURVEYFREQ procedure was used to calculate the coverage rate of safe drinking water, hygienic toilet, and the prevalence of stunting. SURVEYLOGISTIC procedure was used to analyze the relationship between household safe drinking water, hygienic toilet and prevalence of stunting for Chinese children aged 0 to 5 years old in 2013. RESULTS: A total of 32 861 children completed the study. The coverage rate of safe drinking water was 86. 9%. The proportion of water piped into household, a public tab and water from a protected spring or well was 49. 4%, 15. 9% and 15. 6%, respectively. The coverage rate of hygienic toilet was 56. 8%. The proportion of pour-flush toilet and pit latrine were 52. 1% and 4. 7%. The prevalence of stunting for 0 to 5 years old children was 8. 1% in China. The prevalence of stunting were 8. 1% for children aged 0-5 years old with safe household drinking water and 7. 8% for those without safe household drinking water. The difference was not significant(P=0. 882). The prevalence of stunting was 6. 6% for children aged 0-5 years old with hygienic household toilet and 10. 0% for those without hygienic household toilet. The difference was not significant(P=0. 069). There was no significant relationship between household sanitary condition and stunting for children aged 0 to 5 years old. CONCLUSION: Household sanitary conditions, including main source of household drinking water and the main type of household toilet may not be associated with the prevalence of stunting for children aged 0 to 5 years old in this settings.

[Effects of text message intervention on infant growth and anemia at 6 month old].

OBJECTIVE: To investigate the effects of delivering infant feeding knowledge using text messages from cell phones on improving infant growth and anemia. METHODS: A community-based intervention study was conducted in four community health centers in Tumoteyou County, Baotou, Inner Mongolia, one of which was the intervention group and the other three locating nearby were assigned into the control group. Pregnant women were recruited from peri-natal care center. In the intervention group, infant feeding knowledge was sent by the staff of health care center using text messages to the subjects. Meanwhile, no intervention was given in the control group. The growth status and anemia prevalence were assessed at 6 month in both groups. The WHO growth standard for children under 5 years was used to assess the growth status, using the Anthro software v3. 2. 2 to calculate Z scores. Anemia was defined as the concentration of hemoglobin less than 110 g/L. Hemoglobin was measured in duplicate by Hemocue 301 instrument. RESULTS: Totally 214 pregnant women were recruited at the baseline. At the 6 months of postpartum, 192 mothers and infants were investigated. The percentage of lost follow-up was 10.3%. The LAZ, HCZ and hemoglobin concentration of infants were significantly greater,in'the intervention group than in the control group at 6 month old (P < 0.01). The prevalence of stunting (P < 0.01), overweight and obesity (P = 0.02), and anemia (P < 0.01) were significantly lower in the intervention group. CONCLUSIONS: Using text messages from cell phones to deliver infant feeding knowledge may improve the growth and anemia status of infants aged 6 month.

[Relationship between complementary feeding behaviors and anemia for infants and young children in Sichuan, Yunnan and Guizhou province of China].

OBJECTIVE: To examine the relationship between complementary feeding behaviors (CFB) and anemia for infants and young children in Sichuan, Yunnan and Guizhou province of China. METHODS: A total 3 410 children aged 6-24 months were recruited from 12 survey sites in the urban and rural areas of Sichuan, Yunnan and Guizhou provinces by stratified random cluster sampling in 3 age groups (6-8 months, 9-11 months and 12-24 months) from March to July in 2011. The information of CFB for them was collected through a specific questionnaire. According to the comprehensive evaluation method of CFB(including content of food preparation and selection, caregivers' behavior, infants' behavior, feeding environment and environmental hygiene), the scores of CFB were calculated and grouped as low ( < 60% of total score), moderate (60%-80% of total score) and high level ( > 80% of total score). Twenty microliter of fingertip blood was extracted to measure the hemoglobin concentration and anemia rate was calculated. Distribution of CFB level and rate of anemia were compared between urban/rural areas and different age groups. Difference of anemia rate for infants and young children between low/moderate/high CFB level groups was compared. RESULTS: 8.0% (273/3 410) of the children were in low CFB level group, and 56.9% (1 940/3 410) and 35.1% (1 197/3 410) in moderate and high CFB level group respectively. The difference of CFB levels between urban and rural areas was significant (Z = -21.17, P < 0.05), the proportion of high level in urban area was 53.0% (829/1 565) , which was higher than that in rural area (20.0% (368/1845) ). The difference of CFB levels between different age groups was also significant (H = 43.82, P < 0.05). The proportion of high level decreased by increasing age, which was 41.0% (417/1 017) and 29.9% (389/1 300) in 6-8 months and 12-24 months respectively. The average hemoglobin concentration for infants was (119.3 ± 13.8)g/L, and the total anemia rate was 22.4% (765/3 410) . The hemoglobin concentration for infants in urban area ( (123.3 ± 11.3) g/L) was higher than rural area ((115.9 ± 14.8) g/L) (t = 16.75, P < 0.05) and the rate of anemia in urban area (10.5% (165/1 565)) was lower than that in rural area (32.5% (600/1845) ) (χ² = 235.03, P < 0.05) significantly. The rate of anemia was decreased by increasing CFB level(χ² = 73.94, P < 0.05). The rate of anemia in the low CFB level group was the highest (33.7% (92/273) ) while in the high CFB level group was 14.5% (174/1 197), which was the lowest. CONCLUSION: The level of complementary feeding behavior for infants and young children in Sichuan, Yunnan and Guizhou province of China is relatively low and their prevalence of anemia is relatively serious. Complementary feeding behavior is closely associated with anemia for infants and young children.

[Association between complementary feeding frequency and growth of infants and young children aged 6 -24 months old in urban and rural areas of southwest China].

OBJECTIVE: To study the association between complementary feeding frequency (CFF) and growth of infants and young children. METHODS: 3644 infants and young children aged 6 - 24 months from Chengdu, Kunming and Guiyang were selected by stratified random cluster sampling. Data on breastfeeding and formula feeding and complementary feeding for children were collected through the questionnaires. Complementary feeding frequency was assessed using a comprehensive evaluation system. Body weight and length for them were measured. Length for age Z-score (LAZ), weight for age Z-score (WAZ) and weight for length Z-score (WLZ) were calculated. The Spearman rank correlation analysis was used to identify the association between complementary feeding frequency and growth of children. The trend Chi-Square test was used to identify the relationship between complementary feeding frequency and the rate of stunted growth. RESULTS: This study indicated that CFF level was significantly positive associated with WLZ and WAZ in the group of breastfeeding and formula feeding less than three times per day in urban and rural groups, correlation coefficients were 0.10 and 0.11 in urban group and 0.20 and 0.14 in rural group respectively (P < 0.05). Prevalence of wasting reduced with CFF level increasing in rural group. The Z-score did not show significant correlation with CFF level in the group of breastfeeding and formula feeding more than or equal to three times per day in urban and rural groups. CONCLUSION: Complementary feeding frequency is related to growth of infants and young children, especially in rural area of southwest China. The rate of wasting could be controlled by improving complementary feeding frequency of infants and young children.

[Evaluation of pre-pregnancy weight and gestational weight gain among urban and rural women from southwestern China].

OBJECTIVE: To evaluate the situation of pre-pregnancy weight and gestational weight gain (GWG) of women in the urban and rural areas of southwest of China. METHODS: Total 3391 women whose infants and young children aged 6 - 24 months were selected from urban and rural areas of Kunming, Guiyang and Chengdu cities by stratified cluster random sampling. Data of pre-pregnancy height and weight, prenatal weight and pregnancy age for subjects was obtained using a questionnaire. Pre-pregnancy BMI and GWG were calculated. According to the BMI standard for adults from WHO and GWG Guidelines from IOM (2009), the status of pre-pregnancy weight and GWG were assessed. RESULTS: Average BMI of pre-pregnancy for them is (20.3 +/- 2.4). Percentage of normal weight, underweight, and overweight/obesity of pre-pregnancy were 72.7%, 24.1% and 3.2% respectively. The average GWG was (14.9 +/- 6.0) kg, and there was a significant difference between urban and rural group (P < 0.05). Percentage of normal, insufficient and excessive GWG were 35.3%, 31.1% and 33.3% respectively. The rate of excessive GWG in urban group was higher than rural group (P < 0.05), but the rate of insufficient GWG was lower (P < 0.05). The rate of insufficient GWG was higher in women aged below 23 years old (P < 0.05), and the rate of excessive GWG was higher in women aged 24 - 34 years old (P < 0.05). CONCLUSION: It should be pay more attention to improve the underweight of pre-pregnancy and abnormal GWG among women in the southwest of China.