Baby gap
The Biocultural Origins of Human Capital Formation
Oded Galor & Marc Klemp
NBER Working Paper, September 2014
Abstract:
This research explores the biocultural origins of human capital formation. It presents the first evidence that moderate fecundity and thus predisposition towards investment in child quality was conducive for long-run reproductive success within the human species. Using an extensive genealogical record for nearly half a million individuals in Quebec from the sixteenth to the eighteenth centuries, the study explores the effect of fecundity on the number of descendants of early inhabitants in the subsequent four generations. The research exploits variation in the random component of the time interval between the date of first marriage and the first birth to establish that while higher fecundity is associated with a larger number of children, an intermediate level maximizes long-run reproductive success. Moreover, the observed hump-shaped effect of fecundity on long-run reproductive success reflects the negative effect of higher fecundity on the quality of each child. The finding further indicates that the optimal level of fecundity was below the population median, lending credence to the hypothesis that during the Malthusian epoch, the forces of natural selection favored individuals with lower fecundity and thus larger predisposition towards child quality, contributing to human capital formation, the onset of the demographic transition and the evolution of societies from an epoch of stagnation to sustained economic growth.
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Justin Moss & Jon Maner
Human Nature, September 2014, Pages 328-341
Abstract:
The “biological clock” serves as a powerful metaphor that reflects the constraints posed by female reproductive biology. The biological clock refers to the progression of time from puberty to menopause, marking the period during which women can conceive children. Findings from two experiments suggest that priming the passage of time through the sound of a ticking clock influenced various aspects of women’s (but not men’s) reproductive timing. Moreover, consistent with recent research from the domain of life history theory, those effects depended on women’s childhood socioeconomic status (SES). The subtle sound of a ticking clock led low (but not high) SES women to reduce the age at which they sought to get married and have their first child (Study 1), as well as the priority they placed on the social status and long-term earning potential of potential romantic partners (Study 2). Findings suggest that early developmental sensitization processes can interact with subtle environmental stimuli to affect reproductive timing during adulthood.
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A further note on the rises in sex ratio at birth during and just after the two World Wars
William James & John Valentine
Journal of Theoretical Biology, forthcoming
Abstract:
It is well established that in most belligerent countries in World Wars 1 and 2, sex ratios (proportions male at birth) rose during and just after hostilities: then, a year or so later, they declined to normal levels. There is no established explanation for these phenomena. I have previously written on this problem. Here, I elaborate on my previous papers in three ways. First, further evidence (some analytic and some synthetic) is adduced to support the hypothesis that the rises were caused by high parental coital rates. Second, further evidence is adduced to suggest that these high coital rates occurred disproportionately often in couples of whom the man was (or had been) in the armed services. Thirdly, evidence is offered to suggest why such rises in sex ratio were not reported in other conflicts.
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The Relationship Between “Teen Mom” Reality Programming and Teenagers’ Beliefs about Teen Parenthood
Nicole Martins & Robin Jensen
Mass Communication and Society, forthcoming
Abstract:
A survey was conducted in United States high school students (M = 16.57 years of age) from the Midwest to examine whether exposure to “teen mom” reality programming (e.g., 16 and Pregnant, Teen Mom) was related to teens’ perceptions of teen parenthood. Contrary to our hypotheses, analyses revealed that exposure to teen mom reality programming was related to an increased tendency to believe that teen mothers have an enviable quality of life, a high income, and involved fathers. Teens who perceived reality television as realistic were most likely to hold these perceptions. The findings are discussed in terms of cultivation theory.
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Fertility and Financial Development: Evidence from U.S. Counties in the 19th Century
Alberto Basso, Howard Bodenhorn & David Cuberes
NBER Working Paper, September 2014
Abstract:
The old-age security hypothesis establishes that one important reason why parents have a large offspring is to ensure that they will receive financial support from them in old age. In this paper we use data on fertility and financial development in 19th century U.S. to indirectly test this theory. In particular, we explore whether more developed local financial markets reduce the incentives for families to have a large offspring. After controlling for several factors likely to create cross-county variation in fertility levels and for potential spatial correlation, we find that the presence of a bank and the degree of financial development in a given county are strongly associated with lower children-to-women ratios. We find compelling evidence for the old-age security hypothesis.
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Keuntae Kim
Population Research and Policy Review, October 2014, Pages 649-671
Abstract:
It is well established that the timing of childbearing is transmitted from parents to children in the United States. However, little is known about how the intergenerational link has changed over time and under structural and ideological transformations associated with fertility behaviors. This study first considers changes across two birth cohorts from the National Longitudinal Survey of Youth (NLSY) in the extent to which parents’ age at first birth is transmitted to their children. The first cohort includes individuals born during the late 1950s through the early 1960s (NLSY79), while the second includes individuals born in the early 1980s (NLSY97). Results from discrete-time event history analyses indicate that the intergenerational transmission of age at first birth significantly increased for both daughters and sons. These results were confirmed by analyses of data from three cycles of the National Survey of Family Growth spanning the same time period. Over this period, age at first childbirth became increasingly younger for children born to teenage mothers and increasingly older for those born to mothers who began parenthood after age 25. These patterns have important implications for the reproductive polarization hypothesis.
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The Value of Postponing Pregnancy: California’s Paid Family Leave and the Timing of Pregnancies
Shirlee Lichtman-Sadot
B.E. Journal of Economic Analysis & Policy, forthcoming
Abstract:
Conditioning a monetary benefit on individuals’ family status can create distortions, even in individuals’ seemingly personal decisions, such as the birth of a child. Birth timing and its response to various policies has been studied by economists in several papers. However, pregnancy timing – i.e. the timing of conception – and its response to policy announcements has not been examined. This paper makes use of a 21-month lag between announcing California’s introduction of the first paid parental leave program in the United States and its scheduled implementation to evaluate whether women timed their pregnancies in order to be eligible for the expected benefit. Using natality data, documenting all births in the United States, a difference-in-differences approach compares California births to births in states outside of California before the program’s introduction and in 2004, the year California introduced paid parental leave. The results show that the distribution of California births in 2004 significantly shifted from the first half of the year to the second half of the year, immediately after the program’s implementation. While the effect is present for all population segments of new mothers, it is largest for disadvantaged mothers – with lower education levels, of Hispanic origin, younger, and not married. These results shed light on the population segments most affected by the introduction of paid parental leave and on the equitable nature of paid parental leave policies.
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Denial of Abortion Because of Provider Gestational Age Limits in the United States
Ushma Upadhyay et al.
American Journal of Public Health, September 2014, Pages 1687-1694
Objectives: We examined the factors influencing delay in seeking abortion and the outcomes for women denied abortion care because of gestational age limits at abortion facilities.
Methods: We compared women who presented for abortion care who were under the facilities’ gestational age limits and received an abortion (n = 452) with those who were just over the gestational age limits and were denied an abortion (n = 231) at 30 US facilities. We described reasons for delay in seeking services. We examined the determinants of obtaining an abortion elsewhere after being denied one because of facility gestational age limits. We then estimated the national incidence of being denied an abortion because of facility gestational age limits.
Results: Adolescents and women who did not recognize their pregnancies early were most likely to delay seeking care. The most common reason for delay was having to raise money for travel and procedure costs. We estimated that each year more than 4000 US women are denied an abortion because of facility gestational limits and must carry unwanted pregnancies to term.
Conclusions: Many state laws restrict abortions based on gestational age, and new laws are lowering limits further. The incidence of being denied abortion will likely increase, disproportionately affecting young and poor women.
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Danielle Atkins
Journal of Public Health Policy, August 2014, Pages 292–310
Abstract:
In the United States (US), access to emergency contraceptive pills (ECPs) expanded to nationwide in 2006 when regulators allowed Plan B, a brand of emergency contraception, to be sold without prescription. Using data from the National Health and Nutrition Examination Survey from 2001 to 2010, I examined any association between increased access to these ECPs in the US and negative consequences. I found an association between increased access to ECPs and a 2.2 per cent higher probability of any sexual activity, a 5.2 per cent increase in the likelihood of reporting sex with multiple partners, an increase in the average number of partners by 0.35, and a −7.6 per cent decrease in the likelihood of injectable contraceptive use. These results suggest that policies in the US and other countries that expand access to ECPs should be paired with information on ECPs’ lack of protection against sexually transmitted infections and relatively lower efficacy compared to other forms of contraception.
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A Critical Reexamination of the Effect of Antiabortion Legislation in the Post-Casey Era
Marshall Medoff & Christopher Dennis
State Politics & Policy Quarterly, September 2014, Pages 207-227
Abstract:
Michael J. New, in a recent article in this journal, argues that a major reason for the decline in the incidence of abortion since the U.S. Supreme Court’s 1992 Casey decision was the increased number of antiabortion laws — parental involvement laws and informed consent laws — enacted at the state level. However, New’s analysis contained critical data, measurement, methodological and estimation errors. This article details all the errors and then reexamines the effect of restrictive state abortion laws on the incidence of abortion over the period 1985–2005. The empirical results find little evidence that the decline in the number of abortions performed since the U.S. Supreme Court’s 1992 Casey decision was due to the increase in the number of informed consent and parental involvement laws enacted.
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“We're Very Careful …”: The Fertility Desires and Contraceptive Behaviors of Cohabiting Couples
Sharon Sassler & Amanda Miller
Family Relations, October 2014, Pages 538–553
Abstract:
A growing proportion of nonmarital births are to cohabiting couples, though childbearing is more common among moderately educated cohabitors than among cohabiting college graduates. In this study reasons for social class divergence in fertility behavior are explored. Data are from semistructured interviews with 30 working-class and 31 middle-class cohabiting couples. The authors inquired about readiness for parenthood, contraceptive usage, and concurrence about childbearing plans and contraception. Middle-class couples generally utilized the most effective methods, often relied on two methods, concurred regarding fertility goals, and reported contracepting consistently. Among the moderately educated, contraceptive utilization was lower and reliance on less effective methods greater; they expressed greater ambivalence about preventing conception and discussed contraception less than their middle-class counterparts. Less educated respondents also mentioned forgetfulness and cost as reasons for sporadic contraceptive use. The study results highlight the need to deepen understanding of how relational processes and couple dynamics contribute to pregnancy avoidance or conception.
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Racial and Sexual Minority Women’s Receipt of Medical Assistance to Become Pregnant
Bernadette Blanchfield & Charlotte Patterson
Health Psychology, forthcoming
Objective: This study aimed to determine rates at which racial minority (i.e., non-White) and sexual minority (i.e., lesbian and bisexual-identified) women in the United States receive medical help to become pregnant. Income and insurance coverage discrepancies were hypothesized to mediate differences in receipt of medical help as a function of race and sexual orientation.
Method: Two studies compared rates at which adult women ages 21–44 reported receiving medical help to become pregnant as a function of race and sexual orientation, using data from 2 cycles of the National Survey of Family Growth (the 2002 wave in Study 1, and the 2006–2010 wave in Study 2). Mediation analyses controlling for age and education level evaluated whether race and sexual orientation were positively associated with receipt of medical pregnancy help, as mediated by insurance coverage and income.
Results: Heterosexual White women reported receiving medical fertility assistance at nearly double the rates of women who identified as non-White, sexual minority, or both. Differences in rates of help received by White and non-White groups were only partially mediated by insurance coverage and income in both studies. Insurance and income discrepancies accounted for all differences between sexual minority and heterosexual women’s receipt of pregnancy help in Study 1; insurance coverage alone explained differences in Study 2.
Conclusions: Researchers often indicate that economic differences are responsible for health disparities between minority and majority groups, but this may not be the case for all women pursuing medical fertility assistance. Possible origins of these disparities are discussed.
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The Effects of Mortality on Fertility: Population Dynamics after a Natural Disaster
Jenna Nobles, Elizabeth Frankenberg & Duncan Thomas
NBER Working Paper, September 2014
Abstract:
Understanding how mortality and fertility are linked is essential to the study of population dynamics. We investigate the fertility response to an unanticipated mortality shock that resulted from the 2004 Indian Ocean tsunami, which killed large shares of the residents of some Indonesian communities but caused no deaths in neighboring communities. Using population-representative multilevel longitudinal data, we identify a behavioral fertility response to mortality exposure, both at the level of a couple and in the broader community. We observe a sustained fertility increase at the aggregate level following the tsunami, which is driven by two behavioral responses to mortality exposure. First, mothers who lost one or more children in the disaster are significantly more likely to bear additional children after the tsunami. This response explains about 13 percent of the aggregate increase in fertility. Second, women without children before the tsunami initiated family-building earlier in communities where tsunami-related mortality rates were higher, indicating that the fertility of these women is an important route to rebuilding the population in the aftermath of a mortality shock. Such community-level effects have received little attention in demographic scholarship.
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Spatial Analysis of the Causes of Fertility Decline in Prussia
Joshua Goldstein & Sebastian Klüsener
Population and Development Review, September 2014, Pages 497–525
Abstract:
This article contributes to the geographic analysis of fertility decline in the demographic transition in Europe. We reanalyze Galloway, Hammel, and Lee's (1994) Prussian data with spatial analysis methods. Our multivariate analysis provides evidence of the predictive effect of both economic and cultural variables. Furthermore, even after all of the observable economic, social, and cultural variables have been controlled for, our findings show that a significant unexplained geographic clustering of fertility decline remains. We then specify spatial econometric models, which show that in addition to economic and cultural factors, socio-geographic factors such as being adjacent to areas of sharp fertility decline are also needed to understand the pattern of fertility decline. These results provide new support for the role of social diffusion in the process, while allowing for the direct structural effects of economic change.
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A. Gauster, A. Waddington & M.A. Jamieson
Journal of Pediatric and Adolescent Gynecology, forthcoming
Study Objective: This study sought to analyze the effect of strategically timed local preventative education on reducing teen conception rates during known seasonal peaks in March and April.
Interventions: During the month of February 2012, preventative education and media awareness strategies were aimed at parents, teachers, and teens.
Results: Conception rates in teens ≤18 years old were significantly reduced in March and April 2012 compared to March and April 2010 and 2011 (RR = 0.53, 95% CI = 0.32 - 0.88, p-value = 0.0132). There was an increase in conceptions in March and April 2012 compared to 2010 and 2011 among 19 year olds (RR = 1.57, 95% CI = 0.84-2.9, p-value = 0.1500). Effect modification revealed our ≤ 18 year old group and our 19 year old group were distinct groups with different risk estimates (p = 0.0075).
Conclusions: Educational sessions were poorly attended and contraception clinic volume was static. We propose increased parental supervision in response to media reminders as a possible explanation for the reduction in adolescent conceptions (≤18 years old) seen in March 2012.
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Katrina Kimport, Tracy Weitz & Diana Greene Foster
Perspectives on Sexual and Reproductive Health, forthcoming
Context: In the United States, abortion opponents have supported legislation requiring that abortion patients be offered the opportunity to view their preprocedure ultrasound. Little research has examined women's interest in and emotional response to such viewing.
Methods: Data from 702 women who received abortions at 30 facilities throughout the United States between 2008 and 2010 were analyzed. Mixed-effects multinomial logistic regression analysis was used to determine which characteristics were associated with being offered and choosing to view ultrasounds, and with reporting positive or negative emotional responses to viewing. Grounded theory analytic techniques were used to qualitatively describe women's reports of their emotional responses.
Results: Forty-eight percent of participants were offered the opportunity to view their ultrasound, and nulliparous women were more likely than others to receive an offer (odds ratio, 2.3). Sixty-five percent of these women (31% overall) chose to view the image; nulliparous women and those living in a state that regulates viewing were more likely than their counterparts to do so (1.7 and 2.5, respectively). Some 213 women reported emotional responses to viewing; neutral emotions (fine, nothing) were the most commonly reported ones, followed by negative emotions (sad, guilty, upset) and then positive emotions (happy, excited). Women who visited clinics with a policy of offering viewing had increased odds of reporting a negative emotion (2.6).
Conclusions: Ultrasound viewing appears not to have a singular emotional effect. The presence of state regulation and facility policies matters for women's interest in and responses to viewing.
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Posthumous gamete retrieval and reproduction: Would the deceased spouse consent?
Jason Hans
Social Science & Medicine, October 2014, Pages 10–17
Abstract:
Policy and medical decision-making has been hindered by the absence of reliable data on attitudes toward having one's own gametes retrieved posthumously and used to produce a child in the event of an untimely death. The purpose of this study is to directly and empirically examine whether the presumption against consent is justified in the case of posthumous gamete retrieval following sudden death. Respondents (N = 2064) were contacted using a random-digit dialing method that gave every household telephone in the continental United States an equal probability of being contacted, and were asked: “Suppose you were to experience an early death and your spouse wanted to have a biological child with you. Would you or would you not want your spouse to be able to use your sperm/eggs following your death to have a child with you?” Among reproductive age respondents (18–44 years), 70% of males and 58% of females wanted their spouse to be able to use their gametes and, for the most part, attitudes were fairly consistent across demographic characteristics. Religiosity was the best predictor of attitudes — those who described themselves as more religious were less likely to desire posthumous gamete retrieval — but the majority (58%) of respondents who were very religious approved of retrieval. Overall, these data indicate that abandoning the prevailing presumption against consent in favor of a presumption of consent on the part of the deceased will result in the deceased's wishes being honored two and three times more often for females and males, respectively. Three main arguments against a presumption of consent in this context are discussed: autonomy of the deceased, conflict of interest, and the decision-making capacity of a grieving spouse.
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Race, Ethnicity, and the Changing Context of Childbearing in the United States
Megan Sweeney & Kelly Raley
Annual Review of Sociology, 2014, Pages 539-558
Abstract:
In what ways do childbearing patterns in the contemporary United States vary for white, black, and Hispanic women? Why do these differences exist? Although completed family size is currently similar for white and black women, and only modestly larger for Hispanic women, we highlight persistent differences across groups with respect to the timing of childbearing, the relationship context of childbearing, and the extent to which births are intended. We next evaluate key explanations for these differences. Guided by a proximate determinants approach, we focus here on patterns of sexual activity, contraceptive use, and postconception outcomes such as abortion and changes in mothers' relationship status. We find contraceptive use to be a particularly important contributor to racial and ethnic differences in childbearing, yet reasons for varying contraception use itself remain insufficiently understood. We end by reflecting on promising directions for further research.
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Personality and long-term reproductive success measured by the number of grandchildren
Venla Berg et al.
Evolution and Human Behavior, forthcoming
Abstract:
Personality, that is, individual behavioral tendencies that are relatively stable across situations and time, has been associated with number of offspring in many animals, including humans, suggesting that some personality traits may be under natural selection. However, there are no data on whether these associations between personality and reproductive success extend over more than one generation to numbers of grandchildren. Using a large representative sample of contemporary Americans from the Health and Retirement Study (n = 10,688; mean age 67.7 years), we studied whether personality traits of the Five Factor Model were similarly associated with number of children and grandchildren, or whether antagonistic effects of personality on offspring number and quality lead to specific personality traits differently maximizing short and long-term fitness measures. Higher extraversion, lower conscientiousness, and lower openness to experience were similarly associated with both higher number of children and grandchildren in both sexes. In addition, higher agreeableness was associated with higher number of grand-offspring only. Our results did not indicate any quality–quantity trade-offs in the associations between personality and reproductive success. These findings represent the first robust evidence for any species that personality may affect reproductive success over several generations.
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Planning for Motherhood: Fertility Attitudes, Desires And Intentions Among Women with Disabilities
Carrie Shandra, Dennis Hogan & Susan Short
Perspectives on Sexual and Reproductive Health, forthcoming
Context: An estimated 10% of U.S. women of reproductive age report a current disability; however, the relationship between disability, motherhood attitudes and fertility intentions among these women is largely unknown.
Methods: Data from the 2006–2010 National Survey of Family Growth were used to examine attitudes toward motherhood and fertility intentions among 10,782 U.S. women aged 15–44. A series of regression models assessed, separately for mothers and childless women, associations between disability status and women's attitudes and intentions.
Results: Women with and without disabilities held similar attitudes toward motherhood. Among women without children, women with and without disabilities were equally likely to want a child and equally likely to intend to have one. However, childless women with disabilities who wanted and intended to have a child were more likely to report uncertainty about those intentions than were childless women without disabilities (odds ratio, 1.7). Mothers with disabilities were more likely to want another child (1.5), but less likely to intend to have a child (0.5), than were mothers without disabilities.
Conclusions: Deepening understanding of the reproductive health desires, needs and challenges of women with disabilities is essential if the highest quality reproductive health services are to be provided for all.