Birth Weight Distribution Research Articles

Time trends, projections, and spatial distribution of low birthweight in Australia, 2009-2030: Evidence from the National Perinatal Data Collection.

Infants with low birthweight (LBW, birthweight <2500 g) have increased in many high-resource countries over the past two decades. This study aimed to investigate the time trends, projections, and spatial distribution of LBW in Australia, 2009-2030. We used standard aggregate data on 3 346 808 births from 2009 to 2019 from Australia's National Perinatal Data Collection. Bayesian linear regression model was used to estimate the trends in the prevalence of LBW in Australia. Wefound that the prevalence of LBW was 6.18% in 2009, which has increased to 6.64% in 2019 (average annual rate of change, AARC=+0.76%). If the national trend remains the same, the projected prevalence of LBW in Australia will increase to 7.34% (95% uncertainty interval, UI=6.99, 7.68) in 2030. Observing AARC across different subpopulations, the trend of LBW was stable among Indigenous mothers, whereas it increased among non-Indigenous mothers (AARC=+0.81%). There is also an increase among the most disadvantaged mothers (AARC=+1.08%), birthing people in either of two extreme age groups (AARC=+1.99% and +1.53% for <20 years and ≥40 years, respectively), and mothers who smoked during pregnancy (AARC=+1.52%). Spatiotemporal maps showed that some of the Statistical Area level 3 (SA3) in Northern Territory and Queensland had consistently higher prevalence for LBW than the national average from 2014 to 2019. Overall, the prevalence of LBW has increased in Australia during 2009-2019; however, the trends vary across different subpopulations. If trends persist, Australia will not achieve the Sustainable Development Goals (SDGs) target of a 30% reduction in LBW by 2030. Centering and supporting the most vulnerable subpopulations is vital to progress the SDGs and improves perinatal and infant health in Australia.

Feeding a whole-cell inactivated Pichia guilliermondii yeast to gestating and lactating sows in a commercial production system.

A total of 606 sows (PIC 1050) and their progeny (PIC 1050 × 280) were used to determine if feeding gestating and lactating sows a proprietary strain of Pichia guilliermondii as a whole-cell inactivated yeast product (WCY; CitriStim, ADM Animal Nutrition, Quincy, IL) improves sow and litter performance in a commercial production system. Once confirmed pregnant at d 35 post-breeding pregnancy check, sows were fed a basal gestation control (CON) diet (0.55% SID lysine) or the control diet fortified with 0.15% of the WCY replacing corn in the CON diet. Dietary treatments were also fed in lactation (1.05% SID lysine) once sows were moved into farrowing crates on approximately d 112 of gestation until weaning. Sows supplemented with WCY in gestation and lactation had increased total born piglets by 0.45 pigs (P < 0.04), piglets born alive (14.27 vs. 13.85; P < 0.04), and, therefore, heavier born alive litter weights (P < 0.001) compared to CON fed sows. A greater post cross-foster litter size (P < 0.001) meant that litter size at weaning was increased by 0.54 pigs when sows were fed WCY compared to CON (P < 0.001). However, litter weaning weights and 21-d adjusted litter weaning weights were similar (P > 0.158), although numerically greater, for WCY fed sows. Pigs from CON fed sows were 0.35 kg heavier at weaning compared to pigs from WCY fed sows (P < 0.001). This increase in weaning weight of pigs from CON fed sows is partially explained by their 0.93 d longer lactation (P < 0.001) and may also be due to the smaller litter size throughout lactation. The percent of litters treated for scours decreased from 38.3 to 14.2% when sows were fed WCY (P < 0.001). The distribution of birth and weaning weights was not impacted (P > 0.2461) by treatment. In conclusion, feeding gestating and lactating sows a proprietary strain of Pichia guilliermondii as a whole-cell inactivated yeast product increased the number of pigs born and weaned, and decreased the prevalence of scours during lactation.

Secular trends of birth weight and its associations with obesity and hypertension among Southern Chinese children and adolescents.

The association of low or high birth weight (L/HBW) with obesity and hypertension in childhood remains unclear. We aimed to identify the secular trend ofbirth weight distribution and its relationship to obesity and hypertension in Southern Chinese children and adolescents. 6,561 individuals (6-17-year-old) were enrolled by multistage cluster sampling to observed the trend of birth weight distribution and its associated factors. 1,218 were further selected by group matching to investigate thecorrelation between birth weight and obesity or hypertension. Between 1997 and 2008, a significant decline inthe LBW rate and no significant change in the HBW ratewas found. LBW was associated with maternal BMI<18kg/m2 (OR1.79, 95% CI 1.08-2.97) during pregnancy, while maternal BMI between 25.0 and 27.9kg/m2 (OR1.62, 95% CI 1.04-2.52) and paternal BMI>28kg/m2 (OR1.64, 95% CI 1.02-2.63) during pregnancy were associated with HBW. The prevalence of obesity was significantly higher with HBW than normal birth weight (NBW) or LBW (16.73, 6.25 and 5.50%, respectively). The prevalence rates ofsuspected hypertension were 1.62, 1.25 and 1.49% amongLBW, NBW and HBW, respectively (p>0.05). LBW decreased the risks of childhood overweight (OR0.31, 95% CI 0.18-0.54), but had no effect on suspected hypertension. HBW increased the risks of childhood obesity (OR2.19, 95% CI 1.50-3.20), but decreased the risks of suspected hypertension (OR0.22, 95% CI 0.09-0.58). HBW was positively associated with childhood obesity, and parental BMIs management might be one of the measurements to control birth weight to lessen childhood obesity.

Association of geographic distribution and birth weight with sociodemographic factors of the maternal and newborn child of hilly and mountain regions of eastern Nepal: a cross-sectional study

ObjectivesTo determine the association of geographic distribution, and birth weight with sociodemographic factors of the maternal and newborn child of hilly region (lower altitude) and mountain region (high altitude) of...

Association of low birthweight and small for gestational age with maternal ferritin levels: A retrospective cohort study in China.

BackgroundBirthweight have profound impacts on health status throughout lifetime, however, the relationship between maternal ferritin level in pregnancy and birthweight of the newborn remains controversial.ObjectiveThis retrospective cohort research was to analyze the association between maternal ferritin levels during pregnancy with birthweight outcomes, primarily for low birthweight (LBW) and small for gestational age (SGA).MethodsNewborns weighing lower than 2,500 grams were defined as LBW. SGA is defined as birthweight lower than the 10th percentile of the distribution of newborns' birthweight of the same gestational age. Multivariable logistic regressions have been used to explore the association of maternal ferritin levels and birthweight related outcomes, in which the ferritin concentration was logarithm transformed in the model. We further used restricted cubic spline models to explore linear/non-linear dose–response manners of ferritin level and birthweight outcomes.ResultsA total of 3,566 pregnant women were included in the study. In the results of the present study, we observed that maternal ferritin levels were linearly associated with the risk of LBW (p-trend = 0.005) and SGA (p-trend = 0.04), with the adjusted odds ratios (ORs) of 1.78 (95% CI 1.37–2.32) for LBW and 1.87 (95% CI 1.38–2.54) for SGA with an increase in Ln-ferritin concentrations per unit. The adjusted ORs across quartiles of ferritin levels were 2.14 (95% CI 1.03–4.47) for Quartile 2, 3.13 (95% CI 1.47–6.69) for Quartile 3, and 3.63 (95% CI 1.52–8.68) for Quartile 4 for LBW. The adjusted ORs of LBW and SGA among women using supplemental iron were 0.56 (95% CI 0.38, 0.85) and 0.65 (95% CI 0.40, 1.05) compared with non-users, respectively.ConclusionsOur findings found a linear dose–response relationship between ferritin levels and an increased risk of poor birthweight outcomes, suggesting that maternal ferritin level during pregnancy may provide an additional predictor for differentiating poor birthweight related outcomes. Further exploration should be conducted to ensure maternal ferritin thresholds and iron supplement doses.

Birth weight distribution in Golden and Labrador retriever dogs: A similar morphotype with a different trend. Preliminary data.

Birth weight (bW) is considered an indicator of neonatal maturity and a predictor of neonatal mortality. According to its importance, many efforts have been made so far to identify physiological body weight ranges at birth. Due to the high heterogeneity among breeds, optimal bW is difficult to define in dogs. The aim of this study was to carefully analyze the shape and pattern of the bW distribution in dogs. Furthermore, the role of breed on bW determination was specifically investigated in relation to maternal (age, weight, height, diet, season, litter size) and neonatal (sex, malformations, assistance at birth) aspects. For these purposes two canine breeds with very similar phenotypic characteristics, Golden and Labrador retrievers, were selected. An accurate statistical model to explore bW distribution and compare it between Goldens and Labradors was developed. At birth most of the Golden and Labrador pups (estimated 95th percentile) weighed up to 630 g and 500 g, respectively. The estimated 5th percentile of bW distributions was 295 g in Golden and 290 g in Labrador pups. These lowest values could be indicative cut-offs of underweight pups. The probability of neonatal mortality within 1 week of life decreased with increasing bW (P = 0.031) and was higher in Golden than Labrador pups even though this difference was not significant. In conclusion, our results suggest that genetics have a relevant influence on the determination of birth weight which is confirmed to be closely associated with neonatal mortality.

O76 Dietary omega-3 fatty acids in early gestation induce changes in ratio of omega-6 to omega-3 fatty acids in sow plasma and affects distribution of birth weight

O76 Dietary omega-3 fatty acids in early gestation induce changes in ratio of omega-6 to omega-3 fatty acids in sow plasma and affects distribution of birth weight

Implications of the availability and distribution of birth weight on addressing neonatal mortality: population-based assessment from Bihar state of India

ObjectiveA large proportion of neonatal deaths in India are attributable to low birth weight (LBW). We report population-based distribution and determinants of birth weight in Bihar state, and on the...

Improved method for revising the Israel birthweight references.

Birthweight is often used as an indicator of fetal health. Categorization of infants as small or large for gestational age has clinical significance. Due to growth differences between countries, it is important to have local reference data. The aim of the study was to describe an Israel population-based reference of birthweight by gestational age stratified for singletons/multiple births and gender. Data on birthweight and gestational age were obtained for the years 2010-2019 from the Ministry of Health Birth Registry. Implausible birthweight and gestational age values were excluded in a two step process. First, overtly implausible values were excluded using visual mapping. Then, infants whose birthweight was below or above the fifth interquartile range for each completed week were excluded. During the 10-year period there were 1,761,884 infants delivered in Israel; 1,689,696 were included in the analysis. 4.4% of the live born infants were from multiple births. The mean birthweight of singletons (3251g) was 947±4g higher than that of multiples (2304g). The birthweight of the male multiple births began to differ from that of the singletons at 30weeks; female multiple births began to deviate at 31weeks. The increase in birthweight of singletons leveled after 42weeks and those born after 43weeks weighed less than infants born earlier. Comparison of the curves for singletons from the present study to those reported for the years 1993-2001 reveal a similar median but significant differences in the distribution of lower and higher percentiles. Improved data collection and validation permitted inclusion of 96% of births for analysis. Use of interquartile range distribution to exclude values of birthweight/gestational age that were implausible improved validity. Compared to curves reported previously, changes were found in the distribution of birthweights for the upper and lower percentiles. Periodic updates of growth curve references are important.

Comparison of respiratory distress syndrome amongst preterm twins (28-34 Weeks) born within and after two weeks of completion of single antenatal corticosteroid course: A bidirectional cohort study.

BackgroundThe literature on neonatal outcomes in preterm twins delivered before 34 weeks but within and after 14 days of a single initial steroid course is limited.Material and methodsThis bidirectional (226 prospective and 42 retrospectives) cohort study was performed at a tertiary care teaching hospital in South India. We compared the respiratory distress syndrome and neonatal death amongst preterm twins from 28 to 34 weeks born < 14 days (Group A, n=268) and after 14 days (Group B, n=268) of completion of a single course of antenatal steroids. We used multivariable regression analysis (log-binomial model) to adjust for confounding variables. We generated a propensity-matched score with probit regression to analyse outcomes (respiratory distress and neonatal deaths).ResultsThe two groups had significant differences in the distribution of birthweight, gestation period and mode of delivery. On adjusted analysis, the period of gestation below 33 weeks and weight below 1.5 kg had the maximum influence on respiratory and other morbidities, and weight less than 1 kg on neonatal death. [adjusted relative risk (ARR) 26.06, (95%CI=2.37-285.5), p=0.008]. On propensity scoring after matching all these variables, we found an [ARR of 2.0 (95% CI: 1.03-3.88), P=0.017] for neonatal death after 14 days of steroid injection. The ARR for respiratory distress syndrome was 1.13 in those born after 14 days of steroids, though it did not reach statistical significance.ConclusionOn propensity scoring, the steroid-delivery interval more than 14 days was associated with a significantly increased risk (ARR of 2) of neonatal death.

Estimated fetal weight at mid-gestation in prediction of pre-eclampsia in singleton pregnancy.

To examine the distribution of birth weight according to gestational age in pregnancies complicated by pre-eclampsia (PE) and assess the potential value of sonographic estimated fetal weight (EFW) at mid-gestation as a predictor of PE. The data for this study were derived from prospective screening for adverse obstetric outcome in 93 911 women with a singleton pregnancy attending for routine pregnancy care at 19 + 0 to 24 + 6 weeks' gestation in two UK maternity hospitals. This visit included recording of maternal demographic characteristics and medical history, sonographic EFW and measurement of mean arterial pressure (MAP) and uterine artery pulsatility index (UtA-PI). The distribution of birth weight of pregnancies with and those without PE was assessed. The competing-risks model was used to estimate the individual, patient-specific risk of delivery with PE at < 32 and < 37 weeks' gestation and at any gestational age. The areas under the receiver-operating-characteristics curves and detection rates (DRs) of delivery with PE, at a 10% false-positive rate (FPR), were assessed for various combinations of maternal risk factors, EFW, MAP and UtA-PI. McNemar's test was used to determine the significance of difference in DR at a 10% FPR between screening with vs without EFW. The study population contained 2843 (3.0%) pregnancies that subsequently developed PE, including 148 (0.2%) that delivered with PE at < 32 weeks' gestation and 654 (0.7%) that delivered with PE at < 37 weeks. Birth weight was < 10th percentile in 82% of pregnancies with PE delivering at < 32 weeks' gestation and this decreased to 21% of those with PE delivering at ≥ 37 weeks. In screening for delivery with PE at < 32 and < 37 weeks' gestation, the DR, at a 10% FPR, achieved by maternal risk factors (51% and 46%, respectively) was improved by addition of EFW (69% and 51%, respectively). Similarly, addition of EFW improved the performance of screening by a combination of maternal risk factors and MAP from 72% to 80% for PE < 32 weeks and from 57% to 60% for PE < 37 weeks. EFW did not improve the predictive performance of screening by a combination of maternal risk factors, MAP and UtA-PI. In pregnancies complicated by preterm PE, a high proportion of neonates are small-for-gestational age, and sonographic EFW at mid-gestation can improve the prediction of early and preterm PE provided by maternal risk factors and MAP but not the prediction provided by a combination of maternal risk factors, MAP and UtA-PI. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Prevalence and Predictors of Low Birth Weight in a Rural Guatemalan Community.

Background:The intention of our study was to establish the prevalence of low birth weight (LBW) as well as risk factors for LBW in infants born to a convenience sample of women enrolled in a home visitation maternal care program associated with the Center for Human Development in Southwest Trifinio, Guatemala.Methods:This is an observational study analyzing self-reported data from a quality improvement database. We recorded the distribution of birthweights of infants born to women enrolled in Madres Sanas that delivered between October 2018 and December 2019. We grouped women by LBW (<2500g ) and adequate birthweight (≥2500g) infants, and performed bivariate comparisons using sociodemographic, obstetric, and intrapartum data. Using the independent variables shown to have an association with LBW, we then performed a multivariable analysis.Results:There were 226 births among our program participants, 218 with recorded birthweights. The median birthweight was 3175g; 13.8% were LBW (<2500g), higher than Guatemala’s average of 10.9%. Through our bivariate analysis, we determined women with LBW infants were younger, with a median age of 20.8 (IQR [17.8-23.7]) compared to a median age of 23.2 (IQR [19.8-27.3]) among women with infants ≥2500g (P=0.03). Women with LBW infants were also more likely to have fewer than 4 prenatal visits (33.3% vs 19.3%, P=0.04).Conclusion:Two significant findings emerged from our analysis: LBW infants were more commonly born to women who were younger in age and who had received fewer than 4 prenatal visits. These findings are consistent with existing literature on LBW in Latin America. Our study helps to strengthen the data around these associations and gives credence to programming and policy efforts in Latin America that support adequate prenatal care for all and youth education about reproductive health and contraceptive access.

Cross-State Differences in the Processes Generating Black-White Disparities in Neonatal Mortality.

The U.S. Black neonatal mortality rate is more than twice the White rate. This dramatic disparity can be decomposed into two components: (1) disparities due to differences in the distribution of birth weights, and (2) disparities due to differences in birth weight-specific mortality. I utilize this distinction to explore how the social context into which infants are born contributes to gaps in mortality between Black and White neonates. I analyze variation in Black-White differences in neonatal mortality across 33 states using 1995-2010 data. For each state, I calculate the contribution of differences in birth weight distribution versus differences in birth weight-specific mortality to the total disparity in mortality between White and Black neonates. Disparities are largely a product of different birth weight distributions between Black and White newborns (mirroring the pattern for the United States as a whole). However, in at least nine states, differences in birth weight-specific mortality make a notable contribution. This pattern is observed even among those from advantaged sociodemographic backgrounds and is driven by differences in mortality among very low birth weight neonates. This calls attention to inequality in medical care at birth as an importantcontributor to racial disparities in neonatal mortality.

Neonatal mortality in the Maribor region (1997–2008)

Purpose: To provide a summary of neonatal mortality data for a group of 24,044 live births in the Maribor Department of Perinatology between 1997 and 2008.&#x0D; Methods: The National Perinatal Informational System (NPIS) cohort files for 1997–2008 were used for this study. Data are presented using cohorts based on dates of birth and death. The University Clinical Center serves the population of northeastern Slovenia, with 24,044 live births in this 12-year period. Yearly cohorts of neonatal deaths were analyzed by gestational age (GA) distribution, birth weight (BW) distribution, age at death, and cause of death.&#x0D; Results: The average neonatal mortality rate in the 12-year investigated group was 2.2 per 1000 live births with a GA of 28-42 weeks and 4.7 per 1000 live births with a GA of 22-42 weeks. The smallest group, with an extremely low birth weight (ELBW; &lt;1000 g), accounted for approximately 50% of all neonatal deaths, newborns weighing 1000-1500 g accounted for approximately 20% of all neonatal deaths, the group with a BW of 1500-2500 g accounted for 10% of neonatal deaths, and newborns weighing &gt;2500 g accounted for approximately 20% of all neonatal deaths. The largest percentage of neonatal deaths was deaths due to immaturity, and represented 54% of all reported deaths during the investigated period.&#x0D; Conclusion: Oscillations in neonatal mortality rates during the 12 years first occurred in 1997-2005 in direct connection with the number of extremely premature newborns. In the last 4 years of the 12 years we observed a new and better quality indicator, i.e., a lower neonatal mortality rate in spite of the increased preterm delivery rate. Analysis of quality indicators in perinatology should be part of routine clinical care.

Starch supplementation improves the reproductive performance of sows in different glucose tolerance status.

This study was to evaluate the effects of glucose tolerance status, maternal starch supplementation and soybean substitution in diets on the performance of dams and their offspring. Eighty-eight pregnant sows (Landrace × Large White) were selected from an initial total of 120 sows, based on blood glucose test values, and assigned to 4 experimental treatments in a 2 × 2 factorial design. The factors were glucose tolerance status (glucose intolerant [GIT] vs. normal glucose tolerant [NGT]) or dietary treatments (corn starch diet [CS] vs. soybean substitution diet [SS]). A higher area under the curve (AUC) for post-meal glucose was observed (P < 0.05) in the GIT group than in the NGT group on d 109 of gestation. The CS group had a lower value of homeostasis model assessment-insulin resistance than the SS group (P < 0.05) on d 109 of gestation. Corn starch supplementation for sows decreased the stillbirth rate (P < 0.05), regardless of the sows' glucose tolerance status. The villus height of the jejunum and the villus height to crypt depth ratio of the ileum were greater in normal birth weight piglets from the CS group than from the SS group (P < 0.01), and so was the activity of sucrase in the jejunum and ileum (P < 0.01). Compared with the SS group, the CS group showed a reduction in pre-weaning mortality rate, an increase in the number of high-birth-weight piglets, and a decrease in the number of low-birth-weight piglets (P < 0.05) under GIT status. In conclusion, sows fed CS decreased stillbirth rate and improved insulin resistance, as well as improving the intestinal morphology and digestive enzyme activities of their progeny, regardless of glucose tolerance status. Additionally, the CS group improved birth weight distribution and decreased pre-weaning mortality rate of piglets under GIT status.

Association of Hypoxic Ischemic Encephalopathy With Hyponatremia In Term Infants Within First 24 Hours of Life

Background: Electrolytes disturbances observed in hypoxic ischemic encephalopathy can further complicate the already asphyxiated babies Serum sodium is one of the most important electrolytes associated with neuronal activity, routinely serum sodium is added after 24 hour of life in maintenance fluid of neonates but we will monitor the changes in our suspected cases earlier so that early intervention should be done to reduce the perinatal mortality and its fatal outcomes. Aim: To determine the association of hyponatremia with hypoxic ischemic encephalopathy in term infants during first 24 hours of life. Methods: Case control study was carried out at Department of Pediatrics, Aziz Bhatti Shaheed Teaching Hospital Gujrat from12th Feb 2018 to 12th Feb 2019. 134 cases and 134 controls were included in the study. Full term babies (&gt;37 weeks) of either gender was included for both cases and controls. Cases were hypoxic ischemic encephalopathy infants who has history of delayed cry at birth of &gt;5 minutes, respiratory distress and moaning. Hyponatremia was labelled if serum sodium levels are below 130 mmol/lit. Matched controls i.e. healthy neonates from same setting were selected for the study. The serum sodium levels were compared between cases and controls. Results: Serum sodium was unequally distributed among cases &amp; controls (Median±IQR 136±5, 139±8, P value using Mann Whitney U test= 0.01). Hyponatremia was also unequally distributed among cases &amp; controls (3.4% vs 0.4%, P value using Fischer exact test = 0.01). Logistic regression analysis using STEP wise analysis proved that the association found regarding hyponatremia/ serum sodium with hypoxic ischemic encephalopathy is not significant after adjusting for weight and gender of the infant. The distribution of birth weight and gender among cases and controls was similar (P value &gt; 0.05). Conclusion: It is concluded that hyponatremia is not associated with hypoxic ischemic encephalopathy in term infants during first 24 hours of life. Keywords: Hypoxic ischemic encephalopathy, Hyponatremia, Serum sodium, Perinatal asphyxia

Maternal exposure to biomass fuel and birthweight in Kaduna, Northwestern Nigeria: Results from the Child Electronic Growth Monitoring System (CEGROMS)

BACKGROUND AND AIM: Despite the high burden of household air pollution from solid biomass fuel in sub-Saharan Africa, the association of prenatal biomass fuel exposure and birth weight as a continuous variable and independent of preterm birth has not been extensively studied. In this study, we aimed to determine the association of prenatal exposure to biomass fuel with birthweight analyzed as a continuous variable among term births in a Nigerian population. METHODS: This cross-sectional study was conducted at the Child Welfare Clinic of Barau Dikko Teaching Hospital, Kaduna (Kaduna State, Northwestern Nigeria), an urban metropolis with the country's fourth-largest population. We obtained data from the Child Electronic Growth Monitoring System (CEGROMS), a database of all women who brought their newborns to the study site for BCG vaccination and growth monitoring around the time of birth. A total of 1348 women with term births and information on birthweight, cooking fuel type, and other risk factors met the inclusion criteria. We used linear regression to estimate the adjusted associations (β and 95% confidence interval (CI)) between birthweight and biomass fuel exposure. RESULTS:Thirteen percent of mothers used biomass fuel relative to 78.5% using liquified petroleum gas (LPG) and 8.5% using kerosene. On average, infants of mothers exposed to biomass fuel were 111g lighter (95% CI −205,−18), compared with those of mothers using LPG adjusted for maternal age, education, and parity. Kerosene use resulted in a 10 g (95% CI -107; 86) reduction in mean birth weight compared to mothers using LPG. CONCLUSIONS:Maternal exposure to biomass fuel was associated with shifting of the birth weight distribution among term newborns. KEYWORDS: Biomass fuel, House air pollution, birthweight, Nigeria

Prevalence of low birth weight and macrosomia estimates based on heaping adjustment method in China

Low birth weight (< 2500 g; LBW) and macrosomia (> 4000 g) are both adverse birth outcomes with high health risk in short- or long-term period. However, national prevalence estimates of LBW and macrosomia varied partially due to methodology limits in China. The aim of this study is to estimate the prevalence of LBW and macrosomia after taking potential birth weight heaping into consideration in Chinese children under 6 years in 2013. The data were from a nationally representative cross-sectional survey in mainland China in 2013, which consists of 32,276 eligible records. Birth weight data and socio-demographic information was collected using standard questionnaires. Birth weight distributions were examined and LBW and macrosomia estimates were adjusted for potential heaping. The overall prevalence of LBW of Chinese children younger than 6 years was 5.15% in 2013, with 4.57% in boys and 5.68% in girls. LBW rate was higher for children who were minority ethnicity, had less educated mothers, mothers aged over 35 years or under 20 years, or were in lower income household than their counterparts. The overall prevalence of macrosomia of Chinese children younger than 6 years was 7.35% in 2013, with 8.85% in boys and 5.71% in girls. The prevalence of macrosomia increased with increasing maternal age, educational level and household income level. Both LBW and macrosomia varied among different regions and socio-economic groups around China. It is found that estimates based on distribution adjustment might be more accurate and could be used as the foundation for policy-decision and health resource allocation. It would be needed to take potential misclassification of birth weight data arising from heaping into account in future studies.

Study of influence of birth weight on risk of chronic diseases and blood uric acid in adulthood

Objective: To understand the influence of birth weight on the risk of chronic diseases, such as hypertension and diabetes, and the relationship between birth weight and serum uric acid in adulthood. Methods: According to the Chinese Adult Chronic Disease and Nutrition Surveillance Program, a total of 1 131 residents aged 18 years and above were enrolled from Hexi, Nankai, Hongqiao, Wuqing, Jinnan, Baodi and Jizhou districts of Tianjin. The data of birth weight and blood pressure of the residents were collected, and fasting venous blood samples were collected from them to detect uric acid, blood glucose and blood lipids levels. The distribution of birth weight of the surveyed population was described, and the relationship between birth weight and chronic diseases, such as hypertension and diabetes, and the blood uric acid level in adulthood were analyzed. Results: The average birth weight of the surveyed population in Tianjin was 3.37 kg, which was higher in males than in females. No matter overweight/obesity, hypertension or diabetes, the prevalence rate of normal birth weight was the lowest in adulthood. After univariate logistic regression analysis and adjusting for age, sex, smoking and drinking status, it was found that compared with normal birth weight, low birth weight had a stronger correlation with diabetes (OR=2.91,95%CI:1.46-5.76) and dyslipidemia (OR=1.79,95%CI:1.01-3.19) in adulthood. Macrosomia was strongly associated with overweight/obesity in adulthood (OR=1.47, 95%CI:1.08-2.01). There was no significant difference in serum uric acid level among the residents with different birth weights. Conclusions: The low birth weight of the surveyed population in Tianjin was closely related to the risk of diabetes and dyslipidemia in adulthood, and the macrosomia was closely related to the risk of overweight/obesity in adulthood.

Effects of Environmental Factors Growth Traits of Akkaraman Sheep in Çankırı Province

Small ruminants are important contributors of food supply chains throughout the world. In this study, characterization of distributions of birth weight, weaning weight, average daily gain and Kleiber ratio as well as estimation of effects of certain environmental factors on these traits were aimed in Akkaraman sheep raised around Çankırı province. For this purpose, the linear mixed model was fitted to estimate the effect of factors and to obtain the least square means for the traits. The effect of all studied fixed factors on birth weight (BW), weaning weight (WW), average daily weight gain (ADWG) and Kleiber ratio (KR) were found to be significant. The male lambs have more BW and WW than female lambs. The least square mean of ADWG for female lambs was found higher than male lambs. Additionally, the least square mean of the pre-weaning growth traits of single-born lambs were found to be higher than that of twin-born lambs. The birth weights of lambs born in January and February were higher than March. In general, the study reported that pre-weaning growth traits were affected by several environmental factors, which can be used for herd management practices aiming for higher productivity in Akkaraman sheep.