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Periviable infants (i.e., those born in the 20th through 26th weeks of gestation) suffer much morbidity and approximately half die in the first year of life. Attempts to explain and predict these births disproportionately invoke a "dysregulation" narrative. Research inspired by this narrative has not led to efficacious interventions. The clinical community has, therefore, urged novel approaches to the problem. We aim to provoke debate by offering the theory, inferred from microeconomics, that risk tolerant women carry, without cognitive involvement, high risk fetuses farther into pregnancy than do other women. These extended high-risk pregnancies historically ended in stillbirth but modern obstetric practices now convert a fraction to periviable births. We argue that this theory deserves testing because it suggests inexpensive and noninvasive screening for pregnancies that might benefit from the costly and invasive interventions clinical research will likely devise. • Periviable births are increasingly common with medical advances. • These infants account for 40% of infant mortality in the US and suffer great morbidity. • It is thought that periviable births result from the same processes as term births. • We argue instead that they arise from the same processes as spontaneous abortions. • Maternal tolerance for risk may underlie perviable birth and spontaneous abortion. [ABSTRACT FROM AUTHOR]

Abstract: Much medical literature attributes persistently high rates of very low birthweight (VLBW) to “dysregulated” gestation. We offer the alternative view that natural selection conserved well-regulated, though nonconscious, decisional biology that protects the reproductive fitness of women by spontaneously aborting gestations that would otherwise yield frail infants, particularly small males. Modern obstetric practice, however, converts some fraction of these erstwhile spontaneous abortions into live births of very small infants. We further propose that the nonconscious decisional biology of gestation exhibits preferences also seen in consciously made decisions. We hypothesize that the incidence of VLBW among male infants should vary with the population's self-reported intentions to assume financial risk. We apply time-series modeling to monthly birth counts by sex and weight from the Swedish Medical Birth Registry between January 1993 and December 2010. We gauge risk aversion with monthly data from the Micro Index of the Swedish Consumer Tendency Survey (MISCT). Consistent with our argument that nonconscious decisional biology shares risk aversion with conscious decisions, we find that the incidence of VLBW among male infants in Sweden varies with the population's self-reported intentions to assume financial risk. We find increases above expected odds of a very low weight infant among males born 1 month after increases above expected levels of self-reported risk aversion in the Swedish population. We offer this finding as support for the argument that persistently high rates of VLBW arise, at least in part, from a combination of medical interventions and mechanisms conserved by natural selection to protect reproductive fitness. [Copyright &y& Elsevier]

Abstract: In higher latitudes, relatively cold summer weather may constrain outdoor activities that provide relief from chronic stress. Chronic stress can affect human birth outcomes, including the length of gestation and so the birth weight of the infant. We tested the hypothesis that, in Sweden, the odds of very low birth weight (VLBW; <1500g) vary inversely with mean monthly temperature for the summer months. We applied time-series modeling methods to nationally aggregated data on singleton births during the 456 months from January, 1973, through December, 2010. We found elevated odds of VLBW among male infants for relatively cold June and August temperatures. Unpleasant weather may figure in stress-related health outcomes, not only as a stressor, but also as a constraint on restoration. [Copyright &y& Elsevier]

Abstract: The literature offering evolutionary explanations of the male longevity deficit does not address temporal variation in the deficit. This circumstance appears attributable to the fact that natural selection intuitively explains the deficit’s pervasive and persistent nature, while social processes more parsimoniously explain its temporal variability. I offer consilience of these perspectives by speculating that selection in utero, a mechanism both conserved by natural selection and affected by social processes, could induce deviations around trend in the male longevity deficit. I describe the mechanism and offer an empirical test of its possible effect among Swedes – a population with the longest continuous record of sex-specific longevity in annual birth cohorts. I replicate the test with data from England and Wales. Results support the hypothesis that selection in utero against less fit males may explain part of the difference in longevity between males and females in modern populations. [Copyright &y& Elsevier]

Individual-level research reports that adverse environmental conditions during infancy increase the risk of mortality later in life. Extending this model to populations implies what we call the “diminished entelechy” hypothesis in which birth cohorts subjected to virulent environmental insults early in life experience increased mortality at older ages and do not realize their otherwise expected lifespan. Controversy remains as to whether the individual-level findings generalize to populations. We test the “diminished entelechy” hypothesis by measuring the association between infant mortality and life expectancy at age one for males and females born in Sweden (1751–1912), Denmark (1835–1913), and England and Wales (1841–1912). Time-series methods control for trends and other forms of autocorrelation that could confound the associations. Results support diminished entelechy in Sweden and England and Wales, but not in Denmark, in that environmental insults during infancy appear associated with reduced cohort lifespan. We then explored when in the life course the sequelae of infancy appear most salient. We examined cohort associations between infant mortality and mortality during childhood (1–4 years), youth (5–19 years), adulthood (20–54 years), and old-age (55–79 years). We generally find that infant cohort effects appear to “program” the mortality experience in youth, but not in adulthood or old-age. These findings conflict with the notion that improved conditions during infancy shaped the historical decline of old-age mortality. [Copyright &y& Elsevier]

Purpose: To test the hypothesis that labor market contraction is associated with an elevated number of deaths due to sudden infant death syndrome (SIDS). Methods: We apply time-series methods to monthly counts of SIDS deaths and total employment from the state of California beginning January 1989 and ending December 2001. The methods control for trends, seasonal cycles, and other forms of autocorrelation that could induce spurious associations. Results: Decreases in the number of employed persons in California preceded higher than expected monthly values of SIDS cases among black, non-Hispanic White and Hispanic infants. In addition, Blacks and Hispanics appear to respond more strongly than non-Hispanic Whites to economic contraction. Conclusions: We infer support for the hypothesis that economic contraction may inhibit salutary behavior related to SIDS. We discuss various mechanisms through which the economy may affect SIDS and recommend further investigation. [Copyright &y& Elsevier]

Literature describing environmental influences on human conception and gestation implies that the ratio of male to female live births should vary positively over time with the population''s ability to produce and distribute goods and services. No direct test of this hypothesis appears in the literature despite its apparent importance in understanding the biological implications of collective choices. We offer a test based on Swedish data for the years 1862 through 1991. The results support the hypothesis. We argue that the findings have implications for basic science as well as for the debate over the biological effects of social policy. [Copyright &y& Elsevier]

Background: Outpatient prescription medication spending in Sweden has increased sharply since 1974. The Swedish government has raised copayments to reduce medication consumption and limit the growth of medication spending.Objective: The aim of this study was to examine the effect of the 1995 and 1997 copayment increases on Swedish consumption of antidepressants, anxiolytics, sedatives.Methods: Monthly drug-use data for July 1990 through December 1999 for these 3 pharmaceutical classes were obtained from Apoteket AB (Stockholm, Sweden). Data were provided for both sexes in units of defined daily doses per 1000 inhabitants. These series were analyzed with the use of Box-Jenkins autoregressive, integrated, moving-average time-series modeling methods.Results: Dispensing of all 3 drugs classes increased immediately before copayment changes, with the exception of male sedative use at the time of the 1997 reform. Permanent increases in male antidepressant and sedative use occurred before the 1995 copayment reform. Only female antidepressant use was permanently reduced following the 1997 copayment reform.Conclusions: Our findings suggest that Swedish patients'' valuation of mental health medications exceeds the enacted price increases. The permanent increases in male antidepressant and sedative use, beginning in 1995, may have been the result of previous undertreatment. The permanent reduction in female antidepressant use, beginning in 1997, suggests that the price levels reached a threshold that matched or exceeded Swedish women''s valuation of these modific [Copyright &y& Elsevier]

PURPOSE: To test the hypothesis that high unemployment predicts reduced detection of local breast tumors among African American and non-Hispanic white women in the Detroit, Michigan and Atlanta, Georgia SEER catchment areas.METHODS: We test the hypothesis with data for the 156 months from January 1985 through December 1997.RESULTS: In situ and local breast tumors in African American and non-Hispanic white women were less likely to be detected during periods of high unemployment.CONCLUSIONS: Contracting labor markets may impede women with symptoms from getting proper medical attention or distract women from discovering symptoms they would otherwise detect. African American women appear at greatest risk of having a tumor going undetected by virtue of labor market performance. [Copyright &y& Elsevier]

Focuses on the detection for the health effects of medical care reforms using time-series analyses in Norway. Mechanisms of the health care reform financing; Correlation between reforms of medical care financing and indices of population health; Implementation of the generally practiced techniques.

Objective: Research suggests that sociopolitical stressors connected with the 2016 presidential election were associated with increases in preterm birth among Latina women. This study determined whether periviable births (<26 weeks gestation), which exhibit extremely high rates of infant morbidity and mortality, among US Latina women increased above expected levels after the 2016 US presidential election.Methods: We assigned singleton live births among Latina and non-Latina white women in the US to 96 monthly conception cohorts conceived from January 2009 through December 2016. We constructed risk ratios by dividing the rate of periviable birth among Latina women by the rate among non-Latina white women. We used time-series methods to determine if the risk ratio of periviable births in cohorts conceived by Latina women and exposed to the election of 2016 exceeded those expected from autocorrelation and calendar effects.Results: We found an outlying sequence of risk ratios among Latina women starting with the cohort conceived in April and ending with that conceived in November 2016. Increases in the ratios ranged from 0.07 above an expected of 1.61 for the cohort conceived in June, to 0.39 above an expected of 1.27 for the cohort conceived in April.Conclusion: We find that pregnancies in gestation at the time of the 2016 election among Latina women yielded more than expected periviable births. These findings support the argument that the prospect of anti-immigrant policies promised by the Trump campaign sufficiently stressed Latina women to affect the timing of birth. [ABSTRACT FROM AUTHOR]

Anti-immigrant stigma or xenophobia is increasingly pervasive globally. Racism is a determinant of adverse health outcomes, but the epidemiological implications of the recent wave of xenophobic policies have not been well studied. The 2017 travel ban on individuals from Muslim majority countries is an example of such policy efforts in the United States. Using the 2009–2018 National Center for Health Statistics period linked infant birth-death data, we used time series methods to compare the monthly odds of preterm births to women from travel ban countries (Iran, Iraq, Libya, Somalia, Sudan, Syria, and Yemen) after the January 2017 travel ban to the number expected had the ban not been implemented. We estimated our counterfactual from the history of preterm birth among women born in countries included in the ban as well as trends in preterm birth among native-born non-Hispanic (NH) White women. Among the 18,945,795 singleton live births included in our study period (including 191,121 born to women from banned countries), the average monthly rate of births that were preterm birth was 8.5% (range: 6.8%, 10.6%) among women born in the countries affected by the ban and 8.6% (range: 7.7%, 9.8%) among native-born NH White women. Our results show an increase in the odds of preterm birth among infants born to women from travel ban countries in September 2017 and persisting through the cohort born in August 2018. The coefficient for exposed infants born in these months suggests that the odds of preterm birth increased by 6.8% among women from banned countries (p < 0.001). Our results suggest that the first U.S. Executive Order (#13769) of the travel ban targeting individuals from Muslim majority countries may be associated with preterm births. We therefore conclude that structurally xenophobic and racist policies in the U.S. may have a harmful effect on birth outcomes and early life indicators of life-long health outcomes. • The 2017 U.S. Muslim travel ban policy is associated with preterm birth. • Women from travel ban countries residing in the U.S. had higher odds of preterm birth. • Trends in preterm birth remain unchanged for native-born non-Hispanic White women. • Structurally xenophobic policies may have harmful effects on birth outcomes. [ABSTRACT FROM AUTHOR]

On November 4, 2008, Barack Obama was elected the first Black President of the United States. His campaign and electoral win served as a symbol of hope for a more just future, fostering an "Obama effect" that appears associated with improved well-being among non-Hispanic (NH) Black communities. Situating the Obama election within the symbolic empowerment framework, we consider the potentially protective role of the Obama election on NH Black fetal death, an important but understudied measure of perinatal health that has stark racial disparities. Using restricted-use natality files from the National Center for Health Statistics, we proxy fetal death using the male twin rate (number of twins per 1000 male live births). Male twins have a relatively high risk of in utero selection that is sensitive to maternal and environmental stressors, making the twin rate an important marker of fetal death. We then estimate interrupted time-series models to assess the relation between the Obama election and male twin rates among NH Black births across monthly conception cohorts (February 2003–October 2008). Greater-than-expected male twin rates signal less susceptibility to fetal loss. Results indicate a 4.5% higher male twin rate among all NH Black cohorts exposed in utero to the Obama election, after accounting for historical and NH white trends (p < 0.005). The greater-than-expected rates concentrated among births conceived in the months preceding Obama's nomination at the Democratic National Convention and Obama's presidential win. These results suggest a salutary perinatal response to election events that likely reduced NH Black fetal loss. They also indicate the possibility that sociopolitical shifts can mitigate persisting NH Black-NH white disparities in perinatal health. • Greater-than-expected male twin rates signal reduced susceptibility to fetal loss. • Black male twin rates increased for cohorts in utero during Obama's 2008 election. • Increases were greatest for births conceived months prior to primary, election wins. • Symbolic sociopolitical shifts may mitigate persisting perinatal health disparities. [ABSTRACT FROM AUTHOR]

Abstract: This study investigates the role of national independence and women''s political participation on population health using historical lifespan data from Norway. We use time-series methods to analyze data measuring the actual length of time lived by Norwegian birth cohorts spanning a 61 year period surrounding the political emancipation of Norway from Sweden in 1905 and the establishment of a Norwegian monarchy in 1906. The use of a discrete, historical event improves our ability to interpret the population health effects of national independence and women''s political participation as causal. We find a large and significant positive effect on the lifespan of Norwegian females born in the 1906 cohort. Interestingly, the effect does not extend to all living females during the Norwegian drive toward sovereignty. We conclude that the beneficial effects were likely conferred through intrauterine biological transfers and/or neonatal investments specific to the first year of life. [Copyright &y& Elsevier]

Purpose: We use data from California, where 13% of US births occur, to address two questions arising from efforts in the first decade of this century to avoid stillbirths before 25 6/7 weeks of gestation (i.e., in the periviable period). First, did stillbirths decline in the first decade of this century? Second, if stillbirths did decline, did periviable live births increase simultaneously? Answering these questions is important given that periviable infants represent less than 1% of live births but account for roughly 40% of infant mortality and 20% of hospital-based obstetric costs in the United States.Methods: We constructed 240 monthly conception cohorts, starting with that conceived in January 1991, from 9,880,536 singleton pregnancies that reached the 20 0/7 week of gestation. We used time-series design and Box-Jenkins methods that address confounding by autocorrelation, including secular trends and seasonality to answer our questions.Results: We detected a downward shift in stillbirths in April 2007 that coincided with an upward shift in periviable live births.Conclusions: Our findings imply that, since 2007, fewer Californians than expected from history and from the size of conception cohorts reaching 20 0/7 weeks of gestation have had to contend with the sequelae of stillbirths, but more than expected likely have had to contend with those of periviable births. [ABSTRACT FROM AUTHOR]

To evaluate if changes in preterm birth (PTB, <37 weeks of gestation) incidence differed between non-Hispanic (NH) Black and NH white births following the July 1995 Chicago heat wave—among the most severe U.S. heat waves since 1950. We used an ecologic study design. We obtained birth data from January 1990–December 1996 from the National Vital Statistics File to calculate the mean monthly PTB incidence in Chicago's Cook County, Illinois. Births between July 1995 and February 1996 were potentially exposed to the heat wave in utero. We generated time series models for NH Black and NH white births, which incorporated synthetic controls of Cook County based on unexposed counties. We ran a secondary analysis considering socioeconomic status (SES). From 1990–1996, the mean monthly PTB incidence among NH Black births was 18.6% compared to 7.8% among NH white births. The mean monthly PTB incidence among NH Black births from August 1995–January 1996 was 16.7% higher than expected (three additional PTBs per 100 live births per month [95% confidence interval (CI): 1, 5]). A similar increase occurred among low-SES NH Black births. No increase appeared among NH white births. Severe heat waves may increase racial disparities in PTB incidence. [ABSTRACT FROM AUTHOR]

For all climatic regions, mortality due to cold exceeds mortality due to heat. A separate line of research indicates that season of birth predicts lifespan after age 50. This and other literature implies the hypothesis that ambient temperature during gestation may influence cold-related adult mortality. We use data on over 13,500 Swedes from the Uppsala Birth Cohort Study to test whether cold-related mortality in adulthood varies positively with unusually benign ambient temperature during gestation. We linked daily thermometer temperatures in Uppsala, Sweden (1915–2002) to subjects beginning at their estimated date of conception and ending at death or the end of follow-up. We specified a Cox proportional hazards model with time-dependent covariates to analyze the two leading causes of cold-related death in adulthood: ischemic heart disease (IHD) and stroke. Over 540,450 person-years, 1313 IHD and 406 stroke deaths occurred. For a one standard deviation increase in our measure of warm temperatures during gestation, we observe an increased hazard ratio of 1.16 for cold-related IHD death (95% confidence interval: 1.03–1.29). We, however, observe no relation for cold-related stroke mortality. Additional analyses show that birthweight percentile and/or gestational age do not mediate discovered findings. The IHD results indicate that ambient temperature during gestation—independent of birth month—modifies the relation between cold and adult mortality. We encourage longitudinal studies of the adult sequelae of ambient temperature during gestation among populations not sufficiently sheltered from heat or cold waves. [ABSTRACT FROM AUTHOR]

Abstract: Natural selection conserves mechanisms allowing women to spontaneously abort gestations least likely to yield fit offspring. Small gestational size has been proposed as an indicator of fitness observable by maternal biology. Previous research suggests that exposure to ambient stress in utero results in more “culling” of small fetuses and therefore lower rates of small-for-gestational-age (SGA). However, African American women persistently have higher rates of SGA than non-Hispanic white women, despite experiencing more ambient stress. This paper tests whether attenuation of the stress response among highly stressed African American women, as suggested by the weathering hypothesis, may help to explain this apparent inconsistency. We apply time-series modeling to over 2 million African American and non-Hispanic white male term births in California over the period of January 1989 through December 2010. We test for the parabolic (i.e., “U” shaped) relationship, implied by an attenuated stress response, between unusually strong labor market contraction and the rate of SGA among African American term male infants, and a linear relationship among non-Hispanic whites. We find the hypothesized parabolic relationship among term male African American infants. As expected, we find a linear relationship between unexpected layoffs and the rate of SGA among term male non-Hispanic whites. These results are robust to sensitivity analyses. These results may help to explain the high rates of SGA among term male African American infants, despite greater maternal exposure to ambient stress during pregnancy. [Copyright &y& Elsevier]

Abstract: Little research has been conducted on the influence of macroeconomic environments on smoking among blue-collar workers, a group with high smoking prevalence and that is especially vulnerable to the effects of changing economic circumstances. Using data from 52,418 construction workers in the Tobacco Use Supplement to the United States Current Population Survey, we examined the association of labor market shock, cigarette prices, and state antismoking sentiments with smoking status and average number of cigarettes smoked daily. Data analysis included the use of multiple linear and logistic regressions, which employed the sampling and replicate weights to account for sampling design. Unemployed, American–Indian, lower-educated and lower-income workers had higher smoking rates. Labor market shock had a quadratic association, which was non-significant for smoking status and significant for number of cigarettes. The association of cigarette prices with smoking status became non-significant after adjusting for state-level antismoking sentiment. State-level antismoking sentiment had significant quadratic association with smoking status among employed workers and significant quadratic association with number of cigarettes for all smokers. The study highlights how both workplace-based smoking cessation interventions and antismoking sentiments could further contribute to disparities in smoking by employment status. [Copyright &y& Elsevier]