One step back in understanding racial differences in birth weight

In recognition of the biological and social connections in demographic processes, demographers have integrated biological factors into their models of population variation. This new effort has tended to focus on the analysis of fertility and mortality. Edwin J.C.G. van den Oord and David C. Rowe's article, "Racial Differences in Birth Health Risk: A Quantitative Genetic Approach," published in the August 2000 issue of Demography, is part of this effort. These authors use race as a proxy for genetic variation, which subverts even the most positive attempts to understand the impact of genetic variation on demographic processes. The authors' statistical results restate their anachronistic theory of race using latent variables that are not open to empirical testing. Although new data increase the opportunities for the examination of the relationship between biology and demographic processes researchers must be vigilant not to commit the errors of the past by misusing race as a variable.     

Racial differences in infant mortality by cause of death: The impact of birth weight and maternal age

This research examines racial disparities in infant mortality, overall and separately according to cause of death. Using linked birth and death records for the 1975 cohort of live births in Florida, racial differences are initially described and then explained statistically as a product of the distribution of births by birth weight and maternal age. The impact of birth weight is more pronounced than is the effect of maternal age. The analysis suggests the potential utility of examining infant mortality separately by cause of death. Based on the findings, we argue for systematic research focused on factors affecting birth weight.     

Racial differences in birth health risk: A quantitative genetic approach

In the United States the gap between black and white babies' birth weights has remained largely unexplained. Rather than trying to measure all relevant variables, we used a genetically informative design to study the relative importance of genetic and environmental factors. Employing multiple indicators of "birth health risk," we found that the racial differences increased with the magnitude of the shared environmental effects. This suggested that possible genetic effects would not pertain to fetal genes, although genes affecting the mother's physical or physiological characteristics could be important because they contribute to shared environment in our analysis.     

An investigation of racial and ethnic disparities in birth weight in Chicago neighborhoods

We examine differences in the mean birth weights of infants born to non-Hispanic black, non-Hispanic white, and Mexican-origin Hispanic mothers (of any race) in Chicago in 1990 using linear regression models with neighborhood fixed effects. Our pooled models accounted for 64% of the black-white difference and 57% of the black/Mexican-origin Hispanic difference. Differences in the relationship between measured characteristics and birth weight accounted for around half the birth-weight gap between non-Hispanic black and other infants. Efforts to close this gap must go beyond programs that aim to reduce the level of risk factors among black women to address the causes of differences in the effects of risk factors.     

City differences in racial occupational differentiation: A note on the use of odds ratios

This note considers whether city differences in racial occupational distribution are best investigated using measures of nominal differentiation or measures of inequality, and argues that measures of inequality are better suited for testing the prevailing theories of race differences in occupation distribution. It also defends the Index of Net Difference and the Index of Dissimilarity (and other measures of inequality used in previous research) from the criticism that they are flawed because they are sensitive to city differences in occupational structure. Additionally, it explores a new approach for investigating city differences in occupational inequality within the log-linear framework. The logical and empirical arguments offered support the conclusions that racial occupation differences reflect racial stratification, and that variation in racial occupation differences across cities is best understood as the product of city differences in the severity of racial stratification. Thus, future research in this area should continue to focus on measures of inequality rather than measures of nominal differentiation until there are sound theoretical and empirical reasons for conceptualizing race differences in occupational distribution in terms of nominal differentiation.     

The effects of maternal depression,anxiety, and perceived stress during pregnancy on preterm birth: A systematic review

BackgroundExperiencing psychological distress such as depression, anxiety, and/or perceived stress during pregnancy may increase the risk for adverse birth outcomes, including preterm birth. Clarifying the association between exposure and outcome may improve the understanding of risk factors for prematurity and guide future clinical and research practices.AimThe aims of the present review were to outline the evidence on the risk of preterm associated with antenatal depression, anxiety, and stress.MethodsFour electronic database searches were conducted to identify quantitative population-based, multi-centre, cohort studies and randomised-controlled trial studies focusing on the association between antenatal depression, anxiety, and stress, and preterm birth published in English between 1980 and 2013.FindingsOf 1469 electronically retrieved articles, 39 peer-reviewed studies met the final selection criteria and were included in this review following the PRISMA and MOOSE review guidelines. Information was extracted on study characteristics; depression, anxiety and perceived stress were examined as separate and combined exposures. There is strong evidence that antenatal distress during the pregnancy increases the likelihood of preterm birth.ConclusionComplex paths of significant interactions between depression, anxiety and stress, risk factors and preterm birth were indicated in both direct and indirect ways. The effects of pregnancy distress were associated with spontaneous but not with medically indicated preterm birth. Health practitioners engaged in providing perinatal care to women, such as obstetricians, midwives, nurses, and mental health specialists need to provide appropriate support to women experiencing psychological distress in order to improve outcomes for both mothers and infants.     

A note on racial differences in the effecty of female economic opportunity on marriage rates

The previously observed aggregate relationship between marriage rates and female work opportunities is not found among black Americans. Alternative definitions of family formation which take illegitimacy into consideration are explored and also found to be unrelated to black females’ economic opportunities. Although some of the difference may be attributed to measurement error, the significant disparity between the two populations probably reflects substantive differences.     

Born in another country: Women's experience of labour and birth in Queensland,Australia

BackgroundWomen born outside Australia make up more than a fifth of the Queensland birthing population and like migrants in other parts of the world face the challenges of cultural dislocation and possible language barriers. Recognising that labour and birth are major life events the aim was to investigate the experiences of these women in comparison to native-born English speaking women.MethodsSecondary analysis of data from a population based survey of women who had recently birthed in Queensland. Self-reported clinical outcomes and quality of interpersonal care of 481 women born outside Australia who spoke a language other than English at home were compared with those of 5569 Australian born women speaking only English.ResultsAfter adjustment for demographic factors and type of birthing facility, women born in another country were less likely to be induced, but more likely to have constant electronic fetal monitoring (EFM), to give birth lying on their back or side, and to have an episiotomy. Most women felt that they were treated as an individual and with kindness and respect. However, women born outside Australia were less likely to report being looked after ‘very well’ during labour and birth and to be more critical of some aspects of care.ConclusionIn comparing the labour and birth experiences of women born outside the country who spoke another language with native-born English speaking women, the present study presents a largely positive picture. However, there were some marked differences in both clinical and interpersonal aspects of care.     

The misuse of biology in demographic research on racial/ethnic differences: A reply to van den oord and rowe

In an article in the August 2000 issue of Demography titled "Racial Differences in Birth Health Risk: A Quantitative Genetic Approach," van den Oord and Rowe attempted to study the genetic and environmental factors contributing to the black/white gap in infant birth weight. Their findings indicate that this difference may be explained by shared environmental influences rather than by fetal genes. Yet the authors insisted in their conclusions that a strong genetic component still must play a role in determining the racial gap in birth weight, if only through maternal effects. The incompatibility between the authors' findings and their conclusions is due largely to a weakness in their conceptualization of the relationship between race and biology. Their insistence that racial groups represent discrete genetic entities, coupled with a failure to account for interactions between biological and environmental processes, illustrates the methodological and ethical problems that threaten future interdisciplinary research on racial/ethnic disparities in health.     

A formal theory for male-preferring stopping rules of childbearing: sex differences in birth order and in the number of siblings

Through mathematical deductions, this article shows certain macro-demographic consequences of individually employed male-preferring stopping rules in childbearing. It is shown that male-preferring stopping rules generate differences between boys and girls in birth order and in the number of siblings. Two situations are considered regarding the latent probability of having a boy: population homogeneity and population heterogeneity. The sex difference in the number of siblings exists even under population homogeneity, and the difference remains constant when each couple employs a distinct alternative rule. On the other hand, the sex difference in the birth order exists only under population heterogeneity. Substantive implications of these findings are discussed.     

Low birth weight in Aboriginal babies--a need for rethinking Aboriginal women's pregnancies and birthing

Low birth weight in Aboriginal babies has become a persistent quandary as their average birth weight continues to be lower than that of non-Aboriginal babies. Arguments, reviews and research abound to explain this difference which is deemed unacceptable and needing resolution. A précis review of current theories and findings around low birth weight in Aboriginal babies is presented as a background for much needed alternative considerations of this issue. The low birth weight dilemma requires urgent rethinking of Aboriginal women's experiences and feelings of their pregnancies and possible effects on their unborn babies. There is a critical need for empowerment of Aboriginal women that goes beyond rhetoric and dominant ideologies about what is best for them and their babies, and genuinely enables them to assume control and self-determinism in ways that might make a significant difference, including importantly to their babies’ birth weights.     

The effects of child-related benefits and pensions on fertility by birth order: A test on Hungarian data

Using aggregate time-series data from post-war Hungary, we investigated the effect of child-related benefits and pensions on overall fertility and fertility by birth order. The results indicate moderate effects that are robust across a wide range of specifications. According to our estimates, a 1-per-cent increase in child-related benefits would increase total fertility by 0.2 per cent, while the same increase in pensions would decrease fertility by 0.2 per cent. The magnitude of both effects increases by birth order; this is more robust for child-related benefits.     

Residential segregation in urbanized areas of the United States in 1970: An analysis of social class and racial differences

Sociologists and urban commentators often portray metropolitan areas as highly segregated by social class and race. We measured the extent of socioeconomic residential segregation in urbanized areas of the United States in 1970, determined whether cities were as segregated as suburban rings, and compared levels of socioeconomic and racial residential segregation. We found moderate levels of residential segregation of socioeconomic groups. Levels of social class segregation varied little from one urbanized area to another and were about the same in central cities and suburban rings. Racial residential segregation was much greater than the segregation of social classes within either the black or white communities. The extent of racial residential segregation does not vary by educational attainment, occupation, or income.     

Gestational weight gain in obese women by class of obesity and select maternal/newborn outcomes: A systematic review

BackgroundObesity and gestational weight gain impact maternal and fetal risks. Gestational weight gain guidelines are not stratified by severity of obesity.AimConduct a systematic review of original research with sufficient information about gestational weight gain in obese women stratified by obesity class that could be compared to current Institute of Medicine guidelines. Evaluate variance in risk for selected outcomes of pregnancy with differing gestational weight gain in obese women by class of obesity.MethodsA keyword advanced search was conducted of English-language, peer-reviewed journal articles using 3 electronic databases, article reference lists and table of content notifications through January 2015. Data were synthesized to show changes in risk by prevalence.FindingsTen articles met inclusion criteria. Outcomes assessed were large for gestational age, small for gestational age, and cesarean delivery. Results represent nearly 740,000 obese women from four different countries. Findings consistently demonstrated gestational weight gain varies by obesity class and most obese women gain more than recommended by Institute of Medicine guidelines. Obese women are at low risk for small for gestational age and high risk for large for gestational age and risk varies with class of obesity and gestational weight gain. Research suggests the lowest combined risk of selected outcomes with weight gain of 5–9 kg in women with class I obesity, 1 to less than 5 kg for class II obesity and no gestational weight gain for women with class III obesity.ConclusionsGestational weight gain guidelines may need modification for severity of obesity.     

Quantifying the differences in birth outcomes and out-of-pocket costs between Australian Defence Force servicewomen and civilian women: A data linkage study

ObjectivesServicewomen in Defence Forces the world over are constrained in their health service use by defence healthcare policy. These policies govern a woman’s ability to choose who she receives maternity care from and where. The aim of this study was to compare Australian Defence Force (ADF) servicewomen and children’s birth outcomes, health service use, and out-of-pocket costs to those of civilian women and children.MethodsRetrospective cohort study using linked administrative data for women giving birth between 1 July 2012 and 30 June 2018 in Queensland, Australia (n = 365,138 births). Women serving in the ADF at the time of birth were identified as having their care funded by the Department of Defence (n = 395 births). Propensity score matching was used to identify a mixed public/private civilian sample of women to allow for comparison with servicewomen, controlling for baseline characteristics. Sensitivity analysis was also conducted using a sample of civilian women accessing only private maternity care.FindingsNearly all servicewomen gave birth in the private setting (97.22%). They had significantly greater odds of having a caesarean section (OR 1.71, 95%CI 1.29?2.30) and epidural (OR 1.56, 95%CI 1.11?2.20), and significantly lower odds of having a non-instrumental vaginal birth (OR 0.57, 95%CI 0.43?0.75) compared to women in the matched public/private civilian sample. Compared to civilian children, children born to servicewomen had significantly higher out-of-pocket costs at birth ($275.93 ± 355.82), in the first ($214.98 ± 403.45) and second ($127.75 ± 391.13) years of life, and overall up to two years of age ($618.66 ± 779.67) despite similar health service use.ConclusionsADF servicewomen have higher rates of obstetric intervention at birth and also pay significantly higher out-of-pocket costs for their children’s health service utilisation up to 2-years of age. Given the high rates of obstetric intervention, greater exploration of servicewomen’s maternity care experiences and preferences is warranted, as this may necessitate further reform to ADF maternity healthcare policy.     

Prenatal development in rural South Africa: relationship between birth weight and access to fathers and grandparents

Birth weight is an indicator of prenatal development associated with health in infancy and childhood, and may be affected by the family environment experienced by the mother during pregnancy. Using data from KwaZulu-Natal, South Africa, we explore the importance of the mother's access to the father and grandparents of the child during pregnancy. Controlling for household socio-economic indicators and maternal characteristics, the survival and residence of the biological father with the mother are positively associated with birth weight. The type of relationship seems to matter: married women have the heaviest newborns, but co-residence with a non-marital partner is also associated with higher birth weight. Access to the maternal grandmother may also be important: women whose mothers are alive have heavier newborns, but no additional benefit is observed from residing together. Co-residence with any grandparent is not associated with birth weight after controlling for the mother's partnership.     

Race differences in age at first birth and the pace of subsequent fertility: Implications for the minority group status hypothesis

We examine race differences in the effects of age at first birth on the pace of subsequent fertility. If race differences in the pace of fertility persist net of age at first birth and socioeconomic variables, they will be taken as new support for the minority group status hypothesis. Data from the 1973 National Survey of Family Growth are analyzed with the finding that race differences in the pace of fertility are real, giving support to the hypothesis. Implications are drawn suggesting that the proper points at which to examine group differences in fertility are the different stages in the process which culminates in completed fertility, rather than limiting investigation to the final product.