scholarly journals Does the effect of micronutrient supplementation on neonatal survival vary with respect to the percentiles of the birth weight distribution?

2007 ◽  
Vol 2 (1) ◽  
pp. 1-30 ◽  
Author(s):  
Francesca Dominici ◽  
Scott L. Zeger ◽  
Giovanni Parmigiani ◽  
Joanne Katz ◽  
Parul Christian
Keyword(s):  
Birth Weight ◽  
Weight Distribution ◽  
Micronutrient Supplementation ◽  
Birth Weight Distribution

scholarly journals Leisure-Time Physical Activity in Pregnancy and the Birth Weight Distribution: Where Is the Effect?

2012 ◽  
Vol 9 (8) ◽  
pp. 1168-1177 ◽  
Author(s):  
Lanay M. Mudd ◽  
Jim Pivarnik ◽  
Claudia B. Holzman ◽  
Nigel Paneth ◽  
Karin Pfeiffer ◽  
...  
Keyword(s):  
Physical Activity ◽  
Birth Weight ◽  
Quantile Regression ◽  
Gestational Age ◽  
Weight Distribution ◽  
Leisure Time ◽  
Leisure Time Physical Activity ◽  
Large For Gestational Age ◽  
Birth Weight Distribution

Background:Leisure-time physical activity (LTPA) is recommended during pregnancy and has been associated with lower risk of delivering a large infant. We sought to characterize the effect of LTPA across the entire birth weight distribution.Methods:Women enrolled in the Pregnancy Outcomes and Community Health (POUCH) Study (1998–2004) were followed-up in 2007. Follow-up efforts were extensive for a subcohort and minimal for the remainder (nonsubcohort). Thus, 596 subcohort and 418 nonsubcohort women who delivered at term participated. Offspring were categorized as small-, appropriate-, or large-for-gestational-age (SGA, AGA, and LGA, respectively) based on gender and gestational age-specific birth weight z-scores (BWz). At follow-up, women recalled pregnancy LTPA and were classified as inactive, insufficiently active or meeting LTPA recommendations. Linear, logistic, and quantile regression analyses were conducted separately by subcohort status.Results:Meeting LTPA recommendations decreased odds of LGA significantly among the nonsubcohort (aOR = 0.30, 95% CI: 0.14–0.64) and nonsignificantly among the subcohort (aOR = 0.68, 95% CI: 0.34–1.34). In quantile regression, meeting LTPA recommendations reduced BWz among the upper quantiles in the nonsubcohort.Conclusions:LTPA during pregnancy lowered odds of LGA and reduced BWz among the upper quantiles, without shifting the entire distribution. LTPA during pregnancy may be useful for reducing risks of large fetal size.

Birth Weight Distribution as an Indicator of Environmental Effects on Fetal Development

1987 ◽  
Vol 15 (1) ◽  
pp. 11-17 ◽  
Author(s):  
Anders Ericson ◽  
Margareta Eriksson ◽  
Bengt Källén ◽  
Olav Meirik
Keyword(s):  
Birth Weight ◽  
Weight Distribution ◽  
Social Groups ◽  
Marked Change ◽  
High Rate ◽  
Low Birth Weight Infants ◽  
Birth Registry ◽  
Low Socioeconomic ◽  
The Difference ◽  
Birth Weight Distribution

A medical birth registry was used for a geographical analysis of birth weight distribution. Nearly 900 000 Swedish singleton births, 1973–1981, were used for an analysis of the effect of some variables and for standardization for these variables. A marked change in the rate of low birth weight infants (LBW, <2 500 g) was seen in the country between 1976 and 1977. A U-formed effect of maternal age and of parity was demonstrated. A marked interaction between the effects of these two variables existed. Two social groups were compared and the well-known high rate of LBW infants associated with low socioeconomic conditions was demonstrated. Standardization for the variables mentioned influenced this effect only little but reduced the difference between the social groups concerning infants above 3.5 kg weight. The background data were used for analysis of restricted geographical areas.

MODELLING THE RISK FACTORS FOR BIRTH WEIGHT IN TWIN GESTATIONS: A QUANTILE REGRESSION APPROACH

2017 ◽  
Vol 49 (6) ◽  
pp. 744-756 ◽  
Author(s):  
A. John Michael ◽  
Belavendra Antonisamy ◽  
S. Mahasampath Gowri ◽  
Ramasami Prakash
Keyword(s):  
Risk Factors ◽  
Birth Weight ◽  
Low Birth Weight ◽  
Quantile Regression ◽  
Gestational Age ◽  
Weight Distribution ◽  
Ordinary Least Squares ◽  
Child Growth ◽  
Birth Weight Distribution ◽  
Different Parts

SummaryBirth weight is used as a proxy for the general health condition of newborns. Low birth weight leads to adverse events and its effects on child growth are both short- and long-term. Low birth weight babies are more common in twin gestations. The aim of this study was to assess the effects of maternal and socio-demographic risk factors at various quantiles of the birth weight distribution for twin gestations using quantile regression, a robust semi-parametric technique. Birth records of multiple pregnancies from between 1991 and 2005 were identified retrospectively from the birth registry of the Christian Medical College and hospitals in Vellore, India. A total of 1304 twin pregnancies were included in the analysis. Demographic and clinical characteristics of the mothers were analysed. The mean gestational age of the twins was 36 weeks with 51% having preterm labour. As expected, the examined risk factors showed different effects at different parts of the birth weight distribution. Gestational age, chroniocity, gravida and child’s sex had significant effects in all quantiles. Interestingly, mother’s age had no significant effect at any part of the birth weight distribution, but both maternal and paternal education had huge impacts in the lower quantiles (10thand 25th), which were underestimated by the ordinary least squares (OLS) estimates. The study shows that quantile regression is a useful method for risk factor analysis and the exploration of the differential effects of covariates on an outcome, and exposes how OLS estimates underestimate and overestimate the effects of risk factors at different parts of the birth weight distribution.

Race and Birth Weight: The Chinese Example

PEDIATRICS ◽  
1991 ◽  
Vol 87 (5) ◽  
pp. 688-693
Author(s):  
Ray Yip ◽  
Zhu Li ◽  
Wan-Hwa Chong
Keyword(s):  
United States ◽  
Birth Weight ◽  
Low Birth Weight ◽  
Weight Distribution ◽  
Mainland China ◽  
The United States ◽  
Chinese Parent ◽  
White Parent ◽  
Specific Variation ◽  
Birth Weight Distribution

In several studies a race-specific variation in birth weight was suggested between black infants and white infants. The following were compared: (1) the birth weight of Chinese infants born in mainland China, Taiwan, and the United States; and (2) the birth weight of Chinese infants and white infants born in the United States controlled for sociodemographic background. Similarilar birth weight distributions and incidence of low birth weight were found among Chinese infants born in the three areas with markedly different economic conditions. The women in all three areas appear to have met the basic health and nutritional needs for adequate fetal growth. Similar incidence of low birth weight with different birth weight distribution was found among infants born in the United States to two Chinese parents, to one Chinese parent and one white parent, and to two white parents. The variation in birth weight is greater for white infants than for Chinese infants and, consequently, more white infants had larger birth weight. The possibility of race-specific influences on birth weight distribution is suggested by these findings.

Perinatal Statistics

PEDIATRICS ◽  
1987 ◽  
Vol 80 (2) ◽  
pp. 301-302
Author(s):  
JOHN SOFATZIS ◽  
VASSO IOAKIMIDOU
Keyword(s):  
Birth Weight ◽  
Perinatal Mortality ◽  
Weight Distribution ◽  
Newborn Infants ◽  
Mortality Rates ◽  
Specific Mortality ◽  
The Impact ◽  
Birth Weight Distribution ◽  
Good Medical Care ◽  
Over Time

To the Editor.— Evaluation of the effect of good medical care of pregnant women and newborn infants and/or the impact of birth weight distribution on crude perinatal mortality rates is based upon the use of birth weight-specific mortality rates and standardized perinatal mortality rates.1-4 We agree with the suggestion made by Hermansen and Hasan5 that all future reports on perinatal statistics should comply with the recommendations made by WHO. Moreover, meaningful comparisons of standardized perinatal mortality rates over time and place require the use of a standard birth weight distribution.

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