Pregnant with possibilities
Does Parental Consent for Birth Control Affect Underage Pregnancy Rates? The Case of Texas
Sourafel Girma & David Paton
Demography, forthcoming
Abstract:
Previous work based on conjectural responses of minors predicted that the 2003 Texas requirement for parental consent for state-funded birth control to minors would lead to a large increase in underage pregnancies. We use state- and county-level data to test this prediction. The latter allow us to compare the impact of parental consent in counties with and without state-funded family planning clinics. We control for characteristics systematically correlated with the presence of state-funded clinics by combining difference-in-difference estimation with propensity score-weighted regressions. The evidence suggests that the parental consent mandate led to a large decrease in attendance at family planning clinics among teens but did not lead to an increase in underage pregnancies.
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Mate Choice and the Origin of Menopause
Richard Morton, Jonathan Stone & Rama Singh
PLoS Computational Biology, June 2013
Abstract:
Human menopause is an unsolved evolutionary puzzle, and relationships among the factors that produced it remain understood poorly. Classic theory, involving a one-sex (female) model of human demography, suggests that genes imparting deleterious effects on post-reproductive survival will accumulate. Thus, a ‘death barrier' should emerge beyond the maximum age for female reproduction. Under this scenario, few women would experience menopause (decreased fertility with continued survival) because few would survive much longer than they reproduced. However, no death barrier is observed in human populations. Subsequent theoretical research has shown that two-sex models, including male fertility at older ages, avoid the death barrier. Here we use a stochastic, two-sex computational model implemented by computer simulation to show how male mating preference for younger females could lead to the accumulation of mutations deleterious to female fertility and thus produce a menopausal period. Our model requires neither the initial assumption of a decline in older female fertility nor the effects of inclusive fitness through which older, non-reproducing women assist in the reproductive efforts of younger women. Our model helps to explain why such effects, observed in many societies, may be insufficient factors in elucidating the origin of menopause.
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From suffrage to sterilization: Eugenics and the women's movement in 20th century Alberta
Erin Moss, Henderikus Stam & Diane Kattevilder
Canadian Psychology, May 2013, Pages 105-114
Abstract:
In the complicated relationship between early 20th-century feminism and eugenics, Western Canada in general and the Province of Alberta in particular provide a unique case study on the history and practice of the sterilization of the "feeble-minded." While feminism strove to enable women to control their own reproductive capacities, eugenics attempted to exert control over the reproduction of certain segments of society. Ironically, these movements exerted a significant influence on one another during their respective inceptions and were inextricably linked for more than 50 years. This paper discusses how misunderstanding and panic surrounding mental illness served to unite feminism with the eugenics movement. Specifically, the paper explores how first-wave feminism adopted a maternal ideology that embraced the role of "guardians of the race." How these events unfolded within Western Canada and the role that prominent feminists and women's associations played are reconstructed. Ultimately, it is argued that understanding the role that the feminist movement played in the application of eugenics legislation requires consideration of the importance of maternal feminism in the changing relations between the sexes.
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Land Reform and Sex Selection in China
Douglas Almond, Hongbin Li & Shuang Zhang
NBER Working Paper, June 2013
Abstract:
Following the death of Mao in 1976, abandonment of collective farming lifted millions from poverty and heralded sweeping pro-market policies. How did China's excess in male births respond to rural land reform? In newly-available data from over 1,000 counties, a second child following a daughter was 5.5 percent more likely to be a boy after land reform, doubling the prevailing rate of sex selection. Mothers with higher levels of education were substantially more likely to select sons than were less educated mothers. The One Child Policy was implemented over the same time period and is frequently blamed for increased sex ratios during the early 1980s. Our results point to China's watershed economic liberalization as a more likely culprit.
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Unplanned Pregnancy and the Impact on Sibling Health Outcomes
Grace Lordan & Paul Frijters
Health Economics, August 2013, Pages 903-914
Abstract:
This work considers whether planning matters with respect to the effect of a new sibling on another siblings' health. Objective health outcomes are observed before and after a new addition to the family. To date, the literature on family size has focused on a quality-quantity trade-off; the more children in a family, the less resources devoted to each child. We present a theoretical framework which highlights that the quantity-quality trade-off may only be relevant in the case of an unplanned sibling. We also suggest that a planned sibling may result in health gains for the other children. We use two waves of data for more than 1800 children from Peru from the Young Lives Project to test our hypothesis. The data relate to the children at 1 and 5 years. For health outcomes, height for age and weight for age Z are considered. The results highlight significant negative independent effects on height for age when an unplanned sibling is added to the household. In addition, we find positive sibling effects on height for age when a planned sibling arrives. We find only small planning effects for weight for age. We view our hypothesis as a pathway that can further explain the quantity-quality trade-off.
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Duration and Timing of Exposure to Neighborhood Poverty and the Risk of Adolescent Parenthood
Geoffrey Wodtke
Demography, forthcoming
Abstract:
Theory suggests that the impact of neighborhood poverty depends on both the duration and timing of exposure. Previous research, however, has not properly analyzed the sequence of neighborhoods to which children are exposed throughout the early life course. This study investigates the effects of different longitudinal patterns of exposure to disadvantaged neighborhoods on the risk of adolescent parenthood. It follows a cohort of children in the PSID from age 4 to 19 and uses novel methods for time-varying exposures that overcome critical limitations of conventional regression when selection processes are dynamic. Results indicate that sustained exposure to poor neighborhoods substantially increases the risk of becoming a teen parent and that exposure to neighborhood poverty during adolescence may be more consequential than exposure earlier during childhood.
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The Weight of the Crisis: Evidence From Newborns in Argentina
Carlos Bozzoli & Climent Quintana-Domeque
Review of Economics and Statistics, forthcoming
Abstract:
We investigate how prenatal economic fluctuations affected birth weight in Argentina during the period from January 2000 to December 2005, and document its procyclicality. We find evidence that the birth weight of children born to low-educated (less than high-school) mothers is sensitive to macroeconomic fluctuations during both the first and third trimesters of pregnancy, while those of high-educated (high-school or above) mothers only react to the first trimester of pregnancy. Our results are consistent with low-educated women facing credit constraints and suffering from both nutritional deprivation and maternal stress, while high-educated women are only affected by stress.
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Claire Coyne et al.
Journal of Criminal Justice, forthcoming
Purpose: Teenage childbirth is associated with poor psychosocial outcomes for teen mothers. One example is that teen mothers have higher rates of antisocial behavior. The extant research has not been able to determine if teenage motherhood is independently associated with criminal behavior, or if the association is due to selection factors associated with both teenage childbirth and criminal behavior.
Methods: We used longitudinal data from Swedish national registers and sibling-comparisons (both full- and half-siblings) to identify the extent to which there is an independent association between teenage childbirth and mothers' likelihood of criminal conviction between ages 20-30, or if the association is confounded by familial (including genetic or environmental) factors that make sisters similar.
Results: Women who began childbearing as teenagers were more likely to be convicted of a crime in young adulthood compared to women who delayed childbearing. When sisters were compared, the association between teenage childbirth and criminal convictions disappeared. Multivariate behavior genetic analyses suggest genetic and shared environmental account for the association.
Conclusions: The statistical association between teenage childbirth and early adulthood criminal convictions is confounded by genetic and shared environmental factors that influence both the likelihood of teenage childbirth and risk of early adulthood criminal conviction.
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Women Rule: Preferences and Fertility in Australian Households
Elliott Fan & Pushkar Maitra
B.E. Journal of Economic Analysis & Policy, forthcoming
Abstract:
Using a unique dataset from Australia, we investigate how individual fertility preferences translate into fertility realizations. We find consistent evidence that the wife's preference is more important than the husband's preference in predicting subsequent births, no matter whether her initial fertility desire is higher or lower than that of her partner. We also explore the effects of the introduction of the non-means-tested Baby Bonus introduced in 2004 by testing whether the hypothesis that the cash transfers from the scheme increase the bargaining power of the partner with higher fertility desire, thus leading to an increase in fertility for couples with disagreement on fertility plans. Our findings do not support this hypothesis. They also do not suggest any significant fertility-enhancing effect of the scheme.
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Winning the Genetic Lottery: Biasing Birth Sex Ratio Results in More Grandchildren
Collette Thogerson et al.
PLoS ONE, July 2013
Abstract:
Population dynamics predicts that on average parents should invest equally in male and female offspring; similarly, the physiology of mammalian sex determination is supposedly stochastic, producing equal numbers of sons and daughters. However, a high quality parent can maximize fitness by biasing their birth sex ratio (SR) to the sex with the greatest potential to disproportionately outperform peers. All SR manipulation theories share a fundamental prediction: grandparents who bias birth SR should produce more grandoffspring via the favored sex. The celebrated examples of biased birth SRs in nature consistent with SR manipulation theories provide compelling circumstantial evidence. However, this prediction has never been directly tested in mammals, primarily because the complete three-generation pedigrees needed to test whether individual favored offspring produce more grandoffspring for the biasing grandparent are essentially impossible to obtain in nature. Three-generation pedigrees were constructed using 90 years of captive breeding records from 198 mammalian species. Male and female grandparents consistently biased their birth SR toward the sex that maximized second-generation success. The most strongly male-biased granddams and grandsires produced respectively 29% and 25% more grandoffspring than non-skewing conspecifics. The sons of the most male-biasing granddams were 2.7 times as fecund as those of granddams with a 50:50 bias (similar results are seen in grandsires). Daughters of the strongest female-biasing granddams were 1.2 times as fecund as those of non-biasing females (this effect is not seen in grandsires). To our knowledge, these results are the first formal test of the hypothesis that birth SR manipulation is adaptive in mammals in terms of grandchildren produced, showing that SR manipulation can explain biased birth SR in general across mammalian species. These findings also have practical implications: parental control of birth SR has the potential to accelerate genetic loss and risk of extinction within captive populations of endangered species.
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Can below-replacement fertility be desirable?
Erich Striessnig & Wolfgang Lutz
Empirica, August 2013, Pages 409-425
Abstract:
In this paper, we challenge the widespread notion that replacement level fertility is the most desirable level of fertility both for countries currently above and below this level. We discuss possible alternative criteria for choosing one fertility level over another. In accordance with earlier studies, we focus on age dependency as the sole criterion. But we do so by relaxing the strong assumption that all individuals of a given age are equal in terms of their economic contribution to society and introduce education as probably the most relevant observable source of population heterogeneity. Our criterion variable is the education-weighted support ratio and we perform thousands of alternative simulations for different constant levels of fertility, starting from empirically given populations. If education is assumed to present a cost at young age and results in higher productivity during working age, then for most countries the desirable long-term total fertility rate turns out to be well below replacement level.
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Differential Fertility, Human Capital, and Development
Tom Vogl
NBER Working Paper, June 2013
Abstract:
Discussions of cross-sectional fertility heterogeneity and its interaction with economic growth typically assume that the poor have more children than the rich. Micro-data from 48 developing countries suggest that this assumption was false until recently. Over the second half of the twentieth century, the association of economic status with fertility and the association of the number of siblings with their education flipped from generally positive to generally negative. Because large families switched from investing in more education to investing in less, heterogeneity in fertility across families initially increased but now largely decreases average educational attainment. While changes in GDP per capita, women's work, sectoral composition, urbanization, and population health do not explain the reversal, roughly half of it can be attributed to the rising aggregate education levels of the parent generation. The results are consistent with two classes of theories of the fertility transition: (1) those based on changing preferences over the quality and quantity of children and (2) those incorporating subsistence consumption constraints.
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The Baby Boom and Its Causes: What We Know and What We Need to Know
Jan Van Bavel & David Reher
Population and Development Review, June 2013, Pages 257-288
Abstract:
This study analyzes the timing, magnitude, and volume of the mid-twentieth century baby boom in European and non-European Western countries. The baby boom is found to have been especially strong in the non-European countries, fairly strong in some European countries, and quite weak in others. While the boom has often been linked with postwar economic growth and the recuperation of births postponed during the Depression era, we argue that this is only a limited part of the story. In most cases the recovery of the birth rate started well before the end of World War II, a fact not accounted for by existing theories. We investigate the roles played by the recovery of period as well as cohort fertility, the underlying marriage boom, and the recovery of marital fertility. We identify major puzzles for future research, including the reasons for strongly declining ages at marriage and the role played by contraceptive failure in the rise of high-parity births.
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Identifying the Response of Fertility to Financial Incentives
Guy Laroque & Bernard Salanié
Journal of Applied Econometrics, forthcoming
Abstract:
While using financial incentives to increase fertility has become relatively common, the effects of such policies are difficult to assess. We propose an identification strategy that relies on the fact that the variation in wages induces variation in benefits and tax credits among ‘comparable' households. We implement our approach by estimating a discrete-choice model of female participation and fertility using individual data from the French Labor Force Survey and a detailed representation of the French tax-benefit system. Our results suggest that financial incentives have had a significant effect on fertility decisions in France. As an example, we simulate the effects of an additional, unconditional child credit of 150 euros per month. The effects are strongest for the third child.
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Intergenerational Transfer, Human Capital and Long-term Growth in China under the One Child Policy
Xi Zhu, John Whalley & Xiliang Zhao
NBER Working Paper, June 2013
Abstract:
We argue that the demographic changes caused by the one child policy (OCP) may not harm China's long-term growth. This attributes to the higher human capital induced by the intergenerational transfer arrangement under China's poor-functioning formal social security system. Parents raise their children and depend on them for support when they reach an advanced age. The decrease in the number of children prompted by the OCP resulted in parents investing more in their children's educations to ensure retirement consumption. In addition, decreased childcare costs strengthen educational investment through an income effect. Using a calibrated model, a benchmark with the OCP is compared to three counterfactual experiments without the OCP. The output under the OCP is expected to be about 4 percent higher than it would be without the OCP in 2025 under moderate estimates. The output gain comes from a greatly increased educational investment driven by fewer children (11.4 years of schooling rather than 8.1). Our model sheds new light on the prospects of China's long-term growth by emphasizing the OCP's growth enhancing role through human capital formation under the intergenerational transfer arrangement.
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Early Adult Obesity and U.S. Women's Lifetime Childbearing Experiences
Michelle Frisco & Margaret Weden
Journal of Marriage and Family, August 2013, Pages 920-932
Abstract:
Literature from multiple disciplines suggests that women who are obese during early adulthood may accumulate social and physiological impediments to childbearing across their reproductive lives. This led the authors to investigate whether obese young women have different lifetime childbearing experiences than leaner peers by analyzing data from 1,658 female participants in the 1979 National Longitudinal Survey of Youth. Study sample members were nulliparous women ages 20-25 in 1982. The authors examined their childbearing experiences between 1982 and 2006 and found that young women who were obese at baseline had higher odds of remaining childless and increased odds of underachieving fertility intentions than young women who were normal weight at baseline. These results suggest that obesity has long-term ramifications for women's childbearing experiences with respect to whether and how many children women have in general and relative to the number of children they want.
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No direct relationship between human female orgasm rate and number of offspring
Brendan Zietsch & Pekka Santtila
Animal Behaviour, forthcoming
Abstract:
The evolutionary basis of women's orgasm is unknown, but the most favoured theory involves putative physiological processes that accompany orgasm and increase the likelihood of fertilization during intercourse. In a sample of over 8000 female twins and siblings, we show a substantial genetic basis to both orgasm rate and number of offspring. While there was a very weak but significant phenotypic correlation between the two variables, there was no corresponding genetic correlation, suggesting the involvement of environmental confounders. Controlling for relationship length and frequency of sexual intercourse eliminated the significant phenotypic correlation between orgasm rate and number of offspring, which suggests no substantive causal relationship between orgasm and fertility. These results cast doubt on the predominant functional theory of female orgasm.
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Amy Whitaker et al.
Journal of Adolescent Health, forthcoming
Purpose: Long-acting contraceptives, such as the intrauterine device (IUD), show potential for decreasing the incidence of unintended pregnancy. However, use among adolescent and young adult women remains low. We determined factors associated with IUD use among young women.
Methods: We conducted an analysis of nationally representative, cross-sectional data from the 2002 and 2006-2010 National Surveys of Family Growth. We included sexually active women 15-24 years old. We used bivariate analysis to compare proportions of ever-use of any type of IUD in 2002 and in 2006-2010 and multivariable logistic regression to identify correlates of ever-use in 2006-2010.
Results: We found an increase in IUD use in teens 15-19 years old, from .2% to 2.5% (p < .001), and among women 20-24 years old, 2.0% to 5.4% (p < .001). Use increased among nearly all subgroups of respondents. Compared with nulliparous young women, those with one prior delivery and with two or more deliveries were substantially more likely to have used an IUD (adjusted OR 11.43, 95% CI 3.61-36.16, and adjusted OR 13.60, 95% CI 4-46.48, respectively). Young black women were less likely to report IUD use (adjusted OR .32, 95% CI .16-.66), and women whose mothers received at least a high school education were more likely to report use (adjusted OR 2.56, 95% CI 1.22-5.43).
Conclusions: IUD use is increasing among adolescent and young adult women overall and among almost all sociodemographic subgroups. Nonetheless, use remains low, and nulliparous young women are highly unlikely to use the IUD.