Inconceivable
Vladas Griskevicius, Andrew Delton, Theresa Robertson & Joshua Tybur
Journal of Personality and Social Psychology, forthcoming
Abstract:
Why do some people have children early, whereas others delay reproduction? By considering the trade-offs between using one's resources for reproduction versus other tasks, the evolutionary framework of life history theory predicts that reproductive timing should be influenced by mortality and resource scarcity. A series of experiments examined how mortality cues influenced the desire to have children sooner rather than later. The effects of mortality depended critically on whether people grew up in a relatively resource-scarce or resource-plentiful environment. For individuals growing up relatively poor, mortality cues produced a desire to reproduce sooner - to want children now, even at the cost of furthering one's education or career. Conversely, for individuals growing up relatively wealthy, mortality cues produced a desire to delay reproduction - to further one's education or career before starting a family. Overall, mortality cues appear to shift individuals into different life history strategies as a function of childhood socioeconomic status, suggesting important implications for how environmental factors can influence fertility and family size.
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Walter Schumm
Journal of Biosocial Science, November 2010, Pages 721-742
Abstract:
Ten narrative studies involving family histories of 262 children of gay fathers and lesbian mothers were evaluated statistically in response to Morrison's (2007) concerns about Cameron's (2006) research that had involved three narrative studies. Despite numerous attempts to bias the results in favour of the null hypothesis and allowing for up to 20 (of 63, 32%) coding errors, Cameron's (2006) hypothesis that gay and lesbian parents would be more likely to have gay, lesbian, bisexual or unsure (of sexual orientation) sons and daughters was confirmed. Percentages of children of gay and lesbian parents who adopted non-heterosexual identities ranged between 16% and 57%, with odds ratios of 1.7 to 12.1, depending on the mix of child and parent genders. Daughters of lesbian mothers were most likely (33% to 57%; odds ratios from 4.5 to 12.1) to report non-heterosexual identities. Data from ethnographic sources and from previous studies on gay and lesbian parenting were re-examined and found to support the hypothesis that social and parental influences may influence the expression of non-heterosexual identities and/or behaviour. Thus, evidence is presented from three different sources, contrary to most previous scientific opinion, even most previous scientific consensus, that suggests intergenerational transfer of sexual orientation can occur at statistically significant and substantial rates, especially for female parents or female children. In some analyses for sons, intergenerational transfer was not significant. Further research is needed with respect to pathways by which intergenerational transfer of sexual orientation may occur. The results confirm an evolving tendency among scholars to cite the possibility of some degree of intergenerational crossover of sexual orientation.
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China's Below-Replacement Fertility: Government Policy or Socioeconomic Development?
Yong Cai
Population and Development Review, September 2010, Pages 419-440
Abstract:
The article challenges the notion that below-replacement fertility and its local variation in China are primarily attributable to the government's birth planning policy. Data from the 2000 census and provincial statistical yearbooks are used to compare fertility in Jiangsu and Zhejiang, two of the most developed provinces in China, to examine the relationship between socioeconomic development and low fertility. The article demonstrates that although low fertility in China was achieved under the government's restrictive one-child policy, structural changes brought about by socioeconomic development and ideational shifts accompanying the new wave of globalization played a key role in China's fertility reduction.
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An Economic Model of Amniocentesis Choice
Eduardo Fajnzylber, Joseph Hotz & Seth Sanders
NBER Working Paper, August 2010
Abstract:
Medical practitioners typically utilize the following protocol when advising pregnant women about testing for the possibility of genetic disorders: Pregnant women over the age of 35 should be tested for Down syndrome and other genetic disorders; for younger women, such tests are discouraged since they can cause a miscarriage. The logic appears compelling. The rate at which amniocentesis causes a miscarriage is constant while genetic disorders rise over a woman's reproductive years. Hence the potential benefit from testing - being able to terminate a fetus with a genetic disorder - rises with maternal age. We argue that this logic is incomplete. While the benefits to testing rise with age, so do the costs. While undergoing an amniocentesis always entails the risk of miscarriage of a healthy fetus, these costs are lower at early ages, because there is a higher probability of being able to replace a miscarried fetus with a healthy birth at a later age. We develop and calibrate a dynamic model of amniocentesis choice to explore this tradeoff. For parameters that characterize realistic age patterns of chromosomal abnormalities, fertility rates and miscarriages following amniocentesis, our model implies a falling, rather than rising, rate of amniocentesis as women approach menopause.
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Maternal Hurricane Exposure and Fetal Distress Risk
Sammy Zahran, Jeffrey Snodgrass, Lori Peek & Stephan Weiler
Risk Analysis, forthcoming
Abstract:
Logistic regression and spatial analytic techniques are used to model fetal distress risk as a function of maternal exposure to Hurricane Andrew. First, monthly time series compare the proportion of infants born distressed in hurricane affected and unaffected areas. Second, resident births are analyzed in Miami-Dade and Broward counties, before, during, and after Hurricane Andrew. Third, resident births are analyzed in all Florida locales with 100,000 or more persons, comparing exposed and unexposed gravid females. Fourth, resident births are analyzed along Hurricane Andrew's path from southern Florida to northeast Mississippi. Results show that fetal distress risk increases significantly with maternal exposure to Hurricane Andrew in second and third trimesters, adjusting for known risk factors. Distress risk also correlates with the destructive path of Hurricane Andrew, with higher incidences of fetal distress found in areas of highest exposure intensity. Hurricane exposed African-American mothers were more likely to birth distressed infants. The policy implications of in utero costs of natural disaster exposure are discussed.
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Megan Sweeney
Journal of Marriage and Family, October 2010, Pages 1155-1170
Abstract:
Drawing on data from 2 waves of the National Survey of Family Growth (N = 11,065), the current research addressed 2 overarching questions about the reproductive context of cohabitation in the United States. First, did patterns of contraceptive use among cohabitors change during the last 2 decades of the 20th century? Second, did patterns of contraceptive use among cohabiting women tend to vary by education or race/ethnicity? Results point to a growing resemblance between never-married cohabiting women and those in first marriages in the likelihood of using a "very effective" contraceptive method and suggest that cohabitation is most "marriage like" with respect to reproductive behavior among the least educated.
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Do Depression and Low Self-Esteem Follow Abortion Among Adolescents? Evidence from a National Study
Jocelyn Warren, Marie Harvey & Jillian Henderson
Perspectives on Sexual and Reproductive Health, forthcoming
Context: A 2008 report by the American Psychological Association found no evidence that an induced abortion causes mental health problems in adult women. No conclusions were drawn with respect to adolescents because of a scarcity of evidence.
Methods: Data from the National Longitudinal Study of Adolescent Health were used to examine whether abortion in adolescence was associated with subsequent depression and low self-esteem. In all, 289 female respondents reported at least one pregnancy between Wave 1 (1994-1995) and Wave 2 (1996) of the survey. Of these, 69 reported an induced abortion. Population-averaged lagged logistic regression models were used to assess associations between abortion and depression and low self-esteem within a year of the pregnancy and approximately five years later, at Wave 3 (2001-2002).
Results: Abortion was not associated with depression or low self-esteem at either time point. Socioeconomic and demographic characteristics did not substantially modify the relationships between abortion and the outcomes.
Conclusions: Adolescents who have an abortion do not appear to be at elevated risk for depression or low self-esteem in the short term or up to five years after the abortion.
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The Impact of Legalized Abortion on High School Graduation Through Selection and Composition
Stephan Whitaker
Economics of Education Review, forthcoming
Abstract:
This analysis examines whether the legalization of abortion changed high school graduation rates among the children selected into birth. Unless women in all socio-economic circumstances sought abortions to the same extent, increased use of abortion must have changed the distribution of child development inputs. I find that higher abortion ratios are associated with higher graduation rates for black males, but not other demographic groups. In a pooled analysis, I find that abortion has a significant negative impact on graduation rates. The effect disappears when I control for ethnicity. The cohorts born between 1965 and 1979 contained falling shares of whites, who have relatively high graduation rates. Regression results indicate abortion ratios are linked with the fertility differences between ethnicities, which suggests this is a channel of influence. Overall, the relationship between abortion exposure and educational attainment is small. A standard deviation change in abortion might move the national graduation rate by less than three-tenths of a percentage point.
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Obstetrical Intervention and the Singleton Preterm Birth Rate in the United States from 1991-2006
Marian MacDorman, Eugene Declercq & Jun Zhang
American Journal of Public Health, forthcoming
Objectives: We examined the relationship between obstetrical intervention and preterm birth in the United States between 1991 and 2006.
Methods: We assessed changes in preterm birth, cesarean delivery, labor induction, and associated risks. Logistic regression modeled the odds of preterm obstetrical intervention after risk adjustment.
Results: From 1991 to 2006, the percentage of singleton preterm births increased 13%. The cesarean delivery rate for singleton preterm births increased 47%, and the rate of induced labor doubled. In 2006, 51% of singleton preterm births were spontaneous vaginal deliveries, compared with 69% in 1991. After adjustment for demographic and medical risks, the mother of a preterm infant was 88% (95% confidence interval [CI]=1.87, 1.90) more likely to have an obstetrical intervention in 2006 than in 1991. Using new birth certificate data from 19 states, we estimated that 42% of singleton preterm infants were delivered via induction or cesarean birth without spontaneous onset of labor.
Conclusions: Obstetrical interventions were related to the increase in the US preterm birth rate between 1991 and 2006. The public health community can play a central role in reducing medically unnecessary interventions.
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Obstacles to the Integration of Abortion Into Obstetrics and Gynecology Practice
Lori Freedman, Uta Landy, Philip Darney & Jody Steinauer
Perspectives on Sexual and Reproductive Health, September 2010, Pages 146-151
Context: Obstetrics and gynecology residents who are trained in family planning and intend to provide abortions after residency often do not ultimately do so. The extent of the professional barriers physicians face trying to integrate abortion into their practice is unknown.
Methods: In 2006, in-depth interviews were conducted with 30 obstetrician-gynecologists who had graduated 5-10 years earlier from residency programs that included abortion training. Interviews about physicians' experiences with abortion training and practice were coded and analyzed using a grounded theoretical approach.
Results: Eighteen physicians had wanted to offer elective abortions after residency, but only three were doing so at the time of the interview. The majority were unable to provide abortions because of formal and informal policies imposed by their private group practices, employers and hospitals, as well as the strain that doing so might put on relationships with superiors and coworkers. Restrictions on abortion provision sometimes were made explicit when new physicians interviewed for a job, but sometimes became apparent only after they had joined a practice or institution. Several physicians mentioned the threat of violence as an obstacle to providing abortions, but few considered this the greatest deterrent.
Conclusions: The stigma and ideological contention surrounding abortion manifest themselves in professional environments as barriers to the integration of abortion into medical practice. New physicians often lack the professional support and autonomy necessary to offer abortion services.
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The Supply of Birth Control Methods, Education, and Fertility: Evidence from Romania
Cristian Pop-Eleches
Journal of Human Resources, Fall 2010, Pages 971-997
Abstract:
This paper investigates the effect of the supply of birth control methods on fertility behavior by examining Romania's 23-year period of pronatalist policies. Following the lifting of the restrictions in 1989 the immediate decrease in fertility was 30 percent. Women who spent most of their reproductive years under the restrictive regime experienced increases in life-cycle fertility of about 0.5 children. Less-educated women had bigger increases in fertility after policy implementation and larger fertility decreases following the lifting of restrictions. These findings suggest that access to abortion and birth control are significant determinants of fertility levels, particularly for less-educated women.
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Whitney Casares, Maureen Lahiff, Brenda Eskenazi & Bonnie Halpern-Felsher
Journal of Adolescent Health, August 2010, Pages 143-150
Purpose: Adolescents who become pregnant in the United States are at higher risk for a myriad of health concerns. One would predict even more adverse health outcomes among pregnant adolescents who are from disadvantaged racial/ethnic groups; however, previous studies indirectly suggest the opposite. This study examines whether adolescents from racial/ethnic minority groups are less affected by adolescent pregnancy compared to white adolescents.
Methods: We used data from 1,867 adolescents participating in the National Longitudinal Study of Adolescent Health (1995--2001). Our predictor variable was self-reported race/ethnicity. Self-perception of health, educational attainment, and public assistance use in young adulthood were outcome measures. We conducted weighted multivariate logistic regressions and analyzed how adolescent pregnancy modified the relationship between our predictor and outcome variables.
Results: Black and American Indian young women had significantly higher odds than white young women of receiving public assistance (OR, 2.6 and 2.7, respectively; p <.01) and even higher odds if ever pregnant in adolescence (OR, 4.2 and 19.0, respectively; p = .03). White young women had significantly lower odds of high educational attainment if they had a live birth in adolescence as compared to those who had not (OR, 0.1; CI = 0.1--0.4).
Conclusions: These findings support studies that found adolescent pregnancy increases the risk of public assistance use and low educational attainment. The study shows that, for educational attainment, black young women who become pregnant may not be as disadvantaged as their peers, whereas white young women who become pregnant are more disadvantaged.
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Suzanne Noordhuizen, Paul de Graaf & Inge Sieben
Social Indicators Research, October 2010, Pages 163-181
Abstract:
Within a relatively short period of 30 years, public acceptance of voluntary childlessness has increased enormously in the Netherlands. In this paper, we address two research questions, which we answer with data from 13 waves of the repeated cross-sectional survey Cultural Change in the Netherlands (CCN, 1965-1996). First, we investigate to what extent the increasing permissiveness is due to cohort replacement and to intra-cohort change. We find that between 1965 and 1980 the change is primarily due to intra-cohort (period) effects, whereas cohort replacement has become more important since 1980. Second, we address the question which social categories constitute the 10% of the population who do not accept voluntary childlessness. Church attendance - and not religiosity or religious socialization - turns out to be the most important factor. Low levels of income and education also negatively affect the acceptance of voluntary childless.
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Multiple Experiments for the Causal Link between the Quantity and Quality of Children
Joshua Angrist, Victor Lavy & Analia Schlosser
Journal of Labor Economics, October 2010, Pages 773-824
Abstract:
This article presents evidence on the child-quantity/child-quality trade-off using quasi-experimental variation due to twin births and preferences for a mixed sibling sex composition, as well as ethnic differences in the effects of these variables. Our sample includes groups with very high fertility. An innovation in our econometric approach is the juxtaposition of results from multiple instrumental variables strategies, capturing the effects of fertility over different ranges for different sorts of people. To increase precision, we develop an estimator that combines different instrument sets across partially overlapping parity-specific subsamples. Our results are remarkably consistent in showing no evidence of a quantity-quality trade-off.
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The trade-off between fertility and education: Evidence from before the demographic transition
Sascha Becker, Francesco Cinnirella & Ludger Woessmann
Journal of Economic Growth, September 2010, Pages 177-204
Abstract:
The trade-off between child quantity and quality is a crucial ingredient of unified growth models that explain the transition from Malthusian stagnation to modern growth. We present first evidence that such a trade-off indeed existed already in the nineteenth century, exploiting a unique census-based dataset of 334 Prussian counties in 1849. Furthermore, we find that causation between fertility and education runs both ways, based on separate instrumental-variable models that instrument fertility by sex ratios and education by landownership inequality and distance to Wittenberg. Education in 1849 also predicts the fertility transition in 1880-1905.
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East Asian Childbearing Patterns and Policy Developments
Tomas Frejka, Gavin Jones & Jean-Paul Sardon
Population and Development Review, September 2010, Pages 579-606
Abstract:
Childbearing behavior in East Asian countries has changed rapidly during the past half century from an average of five to seven children per family, to replacement-level fertility, and subsequently to unprecedentedly low levels, the lowest in the world. This article analyzes fertility trends in Hong Kong, Japan, singapore, south Korea, and Taiwan using cohort fertility data and methods, then examines social and economic causes of the childbearing trends, and surveys policies pursued to reverse the fertility trends. Postponement of childbearing started in the 1970s with continuously fewer delayed births being "recuperated," which resulted in ultra-low fertility. A rapid expansion of education and employment among women in a patriarchal environment has generated a stark dilemma for women who would like to combine childbearing with a career. Policy responses have been slow, with a more serious attempt to address issues in recent years. Thus far public and private institutions are not devoting sufficient attention to generating broad social change supportive of parenting.
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Achievement test performance in children conceived by IVF
L. Mains, M. Zimmerman, J. Blaine, B. Stegmann, A. Sparks, T. Ansley & B. Van Voorhis
Human Reproduction, October 2010, Pages 2605-2611
Background: Long-term follow-up studies of children conceived by IVF are limited. We examine academic performance on standardized tests [Iowa Tests of Basic Skills/Educational Development (ITBS/ITED)] of children conceived by IVF.
Methods: Parents of children 8-17 years of age at the onset of the study (March 2008) who were conceived by IVF at the University of Iowa Hospitals and Clinics and living in the state of Iowa were contacted by mail. Parents completed questionnaires on their child's health and education and parental education. ITBS/ITED scores from school grades 3-12 were obtained on IVF children and a group of anonymous children matched by grade, year, gender and school district. Scores were analyzed using linear mixed models.
Results: Four hundred and ninety-seven couples were contacted. Two hundred and ninety-five couples (463 children) agreed to participate (59.4% of parents), with ITBS/ITED scores available on 423 children (91.4% of participants). IVF children scored higher than the national mean (P < 0.0001) across all grades and subtests and higher than their matched peers for grades 3-11. A trend toward lower test scores in multiple gestations was present (but not significant). Factors found to affect test scores included parental level of education, maternal age, divorce and child's BMI. Cryopreservation, length of embryo culture and method of insemination did not affect scores.
Conclusions: IVF children scored higher on standardized tests than their matched peers, suggesting that IVF does not have a negative effect on cognitive development. However, long-term follow-up of IVF children is still limited. Further research should be performed on the effect of multiple gestation on academic performance.