Birthdays
Investigating Recent Trends in the U.S. Teen Birth Rate
Melissa Kearney & Phillip Levine
Journal of Health Economics, May 2015, Pages 15–29
Abstract:
We investigate trends in the U.S. rate of teen childbearing between 1981 and 2010, focusing specifically on the sizable decline since 1991. We focus on establishing the role of state-level demographic changes, economic conditions, and targeted policies in driving recent aggregate trends. We offer three main observations. First, the recent decline cannot be explained by the changing racial and ethnic composition of teens. Second, the only targeted policies that have had a statistically discernible impact on aggregate teen birth rates are declining welfare benefits and expanded access to family planning services through Medicaid, but these policies can account for only 12.6 percent of the observed decline since 1991. Third, higher unemployment rates lead to lower teen birth rates and can account for 16 percent of the decline in teen birth rates since the Great Recession began.
---------------------
Fertility and Childlessness in the United States
Thomas Baudin, David de la Croix & Paula Gobbi
American Economic Review, forthcoming
Abstract:
We develop a theory of fertility, distinguishing its intensive margin from its extensive margin. The deep parameters are identified using facts from the 1990 Census: (1) fertility of mothers decreases with education; (2) childlessness exhibits a U-shaped relationship with education; (3) the relationship between marriage rates and education is hump-shaped for women and increasing for men. We estimate that 2.5% of women were childless because of poverty and 8.1% because of high opportunity cost of childrearing. Over time, historical trends in total factor productivity and in education led to a U-shaped response in childlessness rates while fertility of mothers decreased.
---------------------
Health Insurance, Fertility, and the Wantedness of Pregnancies: Evidence from Massachusetts
Maria Apostolova-Mihaylova & Aaron Yelowitz
University of Kentucky Working Paper, January 2015
Abstract:
Health insurance reform in Massachusetts lowered the financial cost of both pregnancy (by increased coverage of pregnancy-related medical events) and pregnancy prevention (by increasing access to reliable contraception and family planning). We examine fertility responses for women of childbearing age in Massachusetts and, on net, find no effect from increasing health insurance coverage. This finding, however, masks substantial heterogeneity. For married women aged 20 to 34 – who have high latent fertility and for whom pregnancies are typically wanted – fertility increased by approximately 1 percent. For unmarried women in the same age range – for whom pregnancies are typically unwanted – fertility declined by 9 percent. Fertility rates changed very little for other groups, in part because of low latent fertility or minimal gains in insurance coverage. Pregnancy wantedness increased in the aggregate through a combination of increasing wanted births and decreasing unwanted births.
---------------------
Ho-Po Crystal Wong
West Virginia University Working Paper, January 2015
Abstract:
The family cap policy that reduces or eliminates incremental welfare benefits for additional births born to mothers already on welfare provides a strong financial disincentive for pregnancy for women on welfare. Hypothetically welfare mothers might also substitute quality for quantity in response to the family cap policy. I study the long term effect of the policy on fertility and low weight births using state-level data from 1989-2012. I find that the policy reduces state level out-of-wedlock birth rate and low weight birth rate by at least 7.5 percent and 1.8 percent respectively. The evidence suggests that the family cap policy might not just produce a deterrent effect on non-marital childbearing but also a quality effect on childbearing: those births that actually occur are endowed with better health in terms of birth weight.
---------------------
Kathryn Kost & Laura Lindberg
Demography, February 2015, Pages 83-111
Abstract:
The premise that unintended childbearing has significant negative effects on the behavior of mothers and on the health of infants strongly influences public health policy and much of current research on reproductive behaviors. Yet, the evidence base presents mixed findings. Using data from the U.S. National Survey of Family Growth, we employ a measure of pregnancy intentions that incorporates the extent of mistiming, as well as the desire scale developed by Santelli et al. (Studies in Family Planning, 40, 87–100, 2009). Second, we examine variation in the characteristics of mothers within intention status groups. Third, we account for the association of mothers’ background characteristics with their pregnancy intentions and with the outcomes by employing propensity score weighting. We find that weighting eliminated statistical significance of many observed associations of intention status with maternal behaviors and birth outcomes, but not all. Mistimed and unwanted births were still less likely to be recognized early in pregnancy than intended ones. Fewer unwanted births received early prenatal care or were breast-fed, and unwanted births were also more likely than intended births to be of low birth weight. Relative to births at the highest level of the desire scale, all other births were significantly less likely to be recognized early in pregnancy and to receive early prenatal care.
---------------------
The unintended: Negative outcomes over the life cycle
Wanchuan Lin & Juan Pantano
Journal of Population Economics, April 2015, Pages 479-508
Abstract:
We quantify the impact of abortion legalization on the incidence of unintended births. While underlying much of the literature on abortion legalization, this effect had only been approximated by previous work. We find a strong decline in the prevalence of unintended births. Moreover, we find that this decline is mainly driven by “pro-choice” women. We then propose an empirical strategy to recover the effect of being “unintended” on life cycle outcomes. We use the differential timing of abortion legalization across states interacted with the mother’s religion (which facilitates or hinders legal abortion take up) to instrument for endogenous pregnancy intention. We find that being unintended causes negative outcomes (higher crime, lower schooling, lower earnings) over the life cycle. Our paper provides an initial step towards quantifying this key mechanism behind many of the well-documented long-term effects associated with changes in reproductive health policy.
---------------------
The Consequences of Teenage Childbearing Before Roe v Wade
Kevin Lang & Russell Weinstein
American Economic Journal: Applied Economics, forthcoming
Abstract:
Using five cycles of the National Survey of Family Growth, we estimate the effect of teen motherhood on education, labor market, and marriage outcomes for teens conceiving from 1940 through 1968. Effects vary by marital status at conception, socioeconomic background, and year. Effects on teens married at conception were limited. However, teen mothers conceiving premaritally obtained less education and had a weaker marriage market. Teen mothers of the 1940s–1950s, affected by subsequent economic and social changes, were disadvantaged in the labor market of the 1970s. In the 1960s, teens for whom motherhood would be costly increasingly avoided pregnancy.
---------------------
Race-Ethnic Differences in the Non-marital Fertility Rates in 2006–2010
Yujin Kim & Kelly Raley
Population Research and Policy Review, February 2015, Pages 141-159
Abstract:
Research in the 1980s pointed to the lower marriage rates of blacks as an important factor contributing to race differences in non-marital fertility. Our analyses update and extend this prior work to investigate whether cohabitation has become an important contributor to this variation. We use data from the 2006–2010 National Survey of Family Growth to identify the relative contribution of population composition (i.e., percent sexually active single and percent cohabiting) versus rates (pregnancy rates, post-conception marriage rates) to race-ethnic variation in non-marital fertility rates (N = 7,428). We find that the pregnancy rate among single (not cohabiting) women is the biggest contributor to race-ethnic variation in the non-marital fertility rate and that contraceptive use patterns among racial minorities explain the majority of the race-ethnic differences in pregnancy rates.
---------------------
Where Have All the Young Men Gone? Using Sex Ratios to Measure Fetal Death Rates
Nicholas Sanders & Charles Stoecker
Journal of Health Economics, May 2015, Pages 30–45
Abstract:
Fetal health is an important consideration in policy formation. Unfortunately, a complete census of fetal deaths, an important measure of overall fetal health, is infeasible, and available data are selectively observed. We consider this issue in the context of the Clean Air Act Amendments of 1970 (CAAA), one of the largest and most influential environmental regulations in the history of the United States. We discuss a model of potential bias in measuring observed fetal deaths, and present the sex ratio of live births as an alternative fetal health endpoint, taking advantage of the finding that males are more vulnerable to side effects of maternal stress in utero. We find the CAAA caused substantial improvements in fetal health, in addition to previously identified reductions in post-natal mortality.
---------------------
V. Jadva, S. Imrie & S. Golombok
Human Reproduction, February 2015, Pages 373-379
Study question: How do the psychological health and experiences of surrogate mothers change from 1 year to 10 years following the birth of the surrogacy child?
Study design, size, duration: This study used a prospective longitudinal design, in which 20 surrogates were seen at two time points: 1 year following the birth of the surrogacy child and 10 years later.
Participants/materials, setting, methods: The 20 surrogates (representing 59% of the original sample) participated in a semi-structured interview and completed self-report questionnaires. Eleven surrogates were gestational carriers and nine surrogates had used their own oocyte (genetic surrogacy). Four were previously known to the intended parents and 16 were previously not known.
Main results and the role of chance: Ten years following the birth of the surrogacy child, surrogate mothers scored within the normal range for self-esteem and did not show signs of depression as measured by the Beck Depression Inventory. Marital quality remained positive over time. All surrogates reported that their expectations of their relationship with the intended parents had been either met or exceeded and most reported positive feelings towards the child. In terms of expectations for the future, most surrogates reported that they would like to maintain contact or would be available to the child if the child wished to contact them. None expressed regrets about their involvement in surrogacy.
Wider implications of the findings: Contrary to concerns about the potentially negative long-term effect of surrogacy, the findings suggest that surrogacy can be a positive experience for some women at least. These findings are important for policy and practice of surrogacy around the world.
---------------------
Understanding Heterogeneity in the Effects of Birth Weight on Adult Cognition and Wages
Justin Cook & Jason Fletcher
NBER Working Paper, January 2015
Abstract:
A large economics literature has shown long term impacts of birth weight on adult outcomes, including IQ and earnings that are often robust to sibling or twin fixed effects. We examine potential mechanisms underlying these effects by incorporating findings from the genetics and neuroscience literatures. We use a sample of siblings combined with an “orchids and dandelions hypothesis”, where the IQ of genetic dandelions is not affected by in utero nutrition variation but genetic orchids thrive under advantageous conditions and wilt in poor conditions. Indeed, using variation in three candidate genes related to neuroplasticity (APOE, BDNF, and COMT), we find substantial heterogeneity in the associations between birth weight and adult outcomes, where part of the population (i.e., “dandelions”) is not affected by birth weight variation. Our results help uncover why birth weight affects adult outcomes.
---------------------
Genotype × Cohort Interaction on Completed Fertility and Age at First Birth
Daniel Briley, Paige Harden & Elliot Tucker-Drob
Behavior Genetics, January 2015, Pages 71-83
Abstract:
Microevolutionary projections use empirical estimates of genetic covariation between physical or psychological phenotypes and reproductive success to forecast changes in the population distributions of those phenotypes over time. The validity of these projections depends on relatively consistent heritabilities of fertility-relevant outcomes and consistent genetic covariation between fertility and other physical or psychological phenotypes across generations. However, well-documented, rapidly changing mean trends in the level and timing of fertility may have been accompanied by differences in the genetic mechanisms of fertility. Using a sample of 933 adult twin pairs from the Midlife Development in the United States study, we demonstrate that genetic influences on completed fertility and age at first birth were trivial for the 1920–1935 birth cohort, but rose substantially for the 1936–1955 birth cohort. For the 1956–1970 birth cohort, genetic influences on completed fertility, but not age at first birth, persisted. Because the heritability of fertility is subject to change dynamically with the social context, it is difficult to project selection pressures or the rate at which selection will occur.
---------------------
Social Discrimination, Stress, and Risk of Unintended Pregnancy Among Young Women
Kelli Stidham Hall et al.
Journal of Adolescent Health, forthcoming
Purpose: Prior research linking young women's mental health to family planning outcomes has often failed to consider their social circumstances and the intersecting biosocial mechanisms that shape stress and depression as well as reproductive outcomes during adolescence and young adulthood. We extend our previous work to investigate relationships between social discrimination, stress and depression symptoms, and unintended pregnancy among adolescent and young adult women.
Methods: Data were drawn from 794 women aged 18–20 years in a longitudinal cohort study. Baseline and weekly surveys assessed psychosocial information including discrimination (Everyday Discrimination Scale), stress (Perceived Stress Scale), depression (Center for Epidemiologic Studies–Depression Scale), and reproductive outcomes. Multilevel, mixed-effects logistic regression and discrete-time hazard models estimated associations between discrimination, mental health, and pregnancy. Baron and Kenny's method was used to test mediation effects of stress and depression on discrimination and pregnancy.
Results: The mean discrimination score was 19/45 points; 20% reported moderate/high discrimination. Discrimination scores were higher among women with stress and depression symptoms versus those without symptoms (21 vs. 18 points for both, p < .001). Pregnancy rates (14% overall) were higher among women with moderate/high (23%) versus low (11%) discrimination (p < .001). Discrimination was associated with stress (adjusted relative risk ratio, [aRR], 2.2; 95% confidence interval [CI], 1.4–3.4), depression (aRR, 2.4; CI, 1.5–3.7), and subsequent pregnancy (aRR, 1.8; CI, 1.1–3.0). Stress and depression symptoms did not mediate discrimination's effect on pregnancy.
Conclusions: Discrimination was associated with an increased risk of mental health symptoms and unintended pregnancy among these young women. The interactive social and biological influences on reproductive outcomes during adolescence and young adulthood warrant further study.
---------------------
Nadia Diamond-Smith & David Bishai
Demography, forthcoming
Abstract:
Sex ratios in India have become increasingly imbalanced over the past decades. We hypothesize that when sex ratios become very uneven, the shortage of girls will increase girls’ future value, leading sex ratios to self-correct. Using data on children under 5 from the last four Indian censuses, we examine the relationship between the sex ratio at one point in time and the change in sex ratio over the next 10 years by district. Fixed-effects models show that when accounting for unobserved district-level characteristics — including total fertility rate, infant mortality rate, percentage literate, percentage rural, percentage scheduled caste, percentage scheduled tribe, and a time trend variable — sex ratios are significantly negatively correlated with the change in sex ratio in the successive 10-year period. This suggests that self-corrective forces are at work on imbalanced sex ratios in India.
---------------------
Solar activity at birth predicted infant survival and women's fertility in historical Norway
Gine Roll Skjærvø, Frode Fossøy & Eivin Røskaft
Proceedings of the Royal Society: Biological Sciences, 22 February 2015
Abstract:
Ultraviolet radiation (UVR) can suppress essential molecular and cellular mechanisms during early development in living organisms and variations in solar activity during early development may thus influence their health and reproduction. Although the ultimate consequences of UVR on aquatic organisms in early life are well known, similar studies on terrestrial vertebrates, including humans, have remained limited. Using data on temporal variation in sunspot numbers and individual-based demographic data (N = 8662 births) from Norway between 1676 and 1878, while controlling for maternal effects, socioeconomic status, cohort and ecology, we show that solar activity (total solar irradiance) at birth decreased the probability of survival to adulthood for both men and women. On average, the lifespans of individuals born in a solar maximum period were 5.2 years shorter than those born in a solar minimum period. In addition, fertility and lifetime reproductive success (LRS) were reduced among low-status women born in years with high solar activity. The proximate explanation for the relationship between solar activity and infant mortality may be an effect of folate degradation during pregnancy caused by UVR. Our results suggest that solar activity at birth may have consequences for human lifetime performance both within and between generations.