With child
Does Education Reduce Teen Fertility? Evidence from Compulsory Schooling Laws
Philip DeCicca & Harry Krashinsky
NBER Working Paper, September 2015
Abstract:
While less-educated women are more likely to give birth as teenagers, there is scant evidence the relationship is causal. We investigate this possibility using variation in compulsory schooling laws (CSLs) to identify the impact of formal education on teen fertility for a large sample of women drawn from multiple waves of the Canadian Census. We find that greater CSL-induced schooling reduces the probability of giving birth as a teenager by roughly two to three percentage points. We find evidence that education affects the timing of births in a way that strongly implies an “incarceration” effect of education. In particular, we find large negative impacts of education on births to young women aged seventeen and eighteen, but little evidence of an effect after these ages, consistent with the idea that being enrolled in school deters fertility in a contemporaneous manner. Our findings are robust to the inclusion of several province-level characteristics including multiple dimensions of school quality, expenditures on public programs and region-specific time trends.
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Jonathan Huang et al.
American Journal of Epidemiology, 1 October 2015, Pages 568-578
Abstract:
Grandmaternal education may be related to grandchild birth weight (GBW) through maternal early-life development; however, conventional regression models may be endogenously confounded. Alternative models employing explicit structural assumptions may provide incrementally clearer evidence. We used data from the US National Longitudinal Study of Adolescent to Adult Health (1995–2009; 1,681 mother-child pairs) to estimate “direct effects” of grandmaternal educational level (less than high school, high school diploma or equivalent, or college degree) at the time of the mother's birth on GBW, adjusted for maternal life-course factors: maltreatment as a child, education and income as an adult, prepregnancy overweight, and prenatal smoking. Using conventional and marginal structural model (MSM) approaches, we estimated 54-g (95% confidence interval: −14.0, 122.1) and 87-g (95% confidence interval: 10.9, 162.5) higher GBWs per increase in educational level, respectively. The MSM allowed simultaneous mediation by and adjustment for prepregnancy overweight. Estimates were insensitive to alternate structural assumptions and mediator parameterizations. Bias analysis suggested that a single unmeasured confounder would have to have a strong influence on GBW (approximately 150 g) or be greatly imbalanced across exposure groups (approximately 25%) to completely explain the findings. Coupling an MSM with sensitivity analyses provides some evidence that maternal early-life socioeconomic environment is directly associated with offspring birth weight.
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Common Law Marriage and Teen Births
Shoshana Amyra Grossbard & Victoria Vernon
San Diego State University Working Paper, July 2015
Abstract:
Using microdata from Current Population Survey Fertility supplements 1990-2010 we examine whether Common Law Marriage (CLM) laws in the US affect teen birth rates. CLM effects are identified through cross-state and time variation, as four states repealed the law over the period of study. We find that in the states where CLM laws were first available but then repealed the odds that teens would become new mothers increased, with a larger increase among young black teens. When we include dummies for CLM at various times around the timing of the repeal, it turns out that the likelihood of becoming a mother is most affected by availability of CLM between 1 and 4 years prior to the repeal. There is a small negative effect of CLM on older women becoming mothers. To the extent that they reduce teen births CLM laws are socially desirable and worthy of further study.
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Labor Market Conditions and US Teen Birth Rates, 2001–2009
Robert Cherry & Chun Wang
Journal of Family and Economic Issues, September 2015, Pages 408-420
Abstract:
Using unemployment rates as the sole labor market explanatory variable, most previous studies have concluded that employment conditions do not systematically influence teen birth rates. By contrast, this study found that birth rates were positively correlated with male employment rates (20–24 years old) and negatively correlated with the real minimum wage. Teen birth rates were also positively correlated with teen gonorrhea infection rates; and for the older teens (18–19 years old), by a measure of illegal drug use. By contrast, alcohol use was negatively correlated with teen birth rates. Finally, teen female employment rates were positively correlated with teen birth rates in weak labor market areas, suggesting that better job opportunities might increase teen birth rates among disadvantaged youth. Given the persistence of young adult birth rates among disadvantaged youth, policy recommendations to eliminate the marriage penalty they face are offered.
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Low Fertility, Socioeconomic Development, and Gender Equity
Thomas Anderson & Hans-Peter Kohler
Population and Development Review, September 2015, Pages 381–407
"Specifically, we argue that the onset and long-term pace of socioeconomic development are inherently linked with a key driver of fertility variation within developed countries: differing gender equity regimes. Moreover, we argue that these gender equity regimes are not static, but instead, dynamic and closely tied to changes in fertility through a demographic feedback mechanism: a gender-equity dividend. This gender-equity dividend is the result of the following process: below-replacement fertility brought about by work-family conflicts yields age-structures at young adulthood that are characterized by a relative scarcity of women relative to men (given the prevailing gender-differences in the age at marriage), which in turn facilitates changes in gender-norms and the rise of greater gender-equity. Greater gender equity is then likely to help raise or stabilize fertility in low-fertility high-income countries."
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Interpregnancy Interval and Risk of Autism Spectrum Disorders
Ousseny Zerbo et al.
Pediatrics, October 2015, Pages 651-657
Objective: To determine whether subsequent births after short and long interpregnancy intervals (IPIs) are associated with risk of autism spectrum disorder (ASD).
Method: We assessed the association between IPI and ASD risk in a cohort of 45 261 children born at Kaiser Permanente Northern California (KPNC) between 2000 and 2009. Children with ASD were identified from International Classification of Diseases, Revision 9 diagnostic codes 299.0, 299.8, and 299.9 recorded in KPNC electronic medical records. IPI was defined as the time from the birth of the first child to the conception of the second child. Survival analysis and logistic regression models were used to evaluate the association between IPI and risk of ASD in second-born children.
Results: Children born after an IPI of <12 months or ≥72 months had a 2- to 3-fold increased ASD risk compared with children born after an interval of 36 to 47 months. Respective adjusted hazard ratios (95% confidence intervals) were as follows: <6 months, 3.0 (1.9–4.7); 6 to 8 months, 2.1 (1.4–3.3); 9 to 11 months, 1.9 (1.3–2.1); 12 to 23 months, 1.5 (1.1–2.1); and ≥72 months, 2.4 (1.5–3.7). The results are not explained by maternal BMI or change in BMI between pregnancies or by parental age, maternal antidepressant medication use, or unfavorable events occurring during the first or second pregnancy.
Conclusions: Children born after interpregnancy intervals <2 years or >6 years may be at increased risk of ASD. The mechanism explaining this association is unknown, and more research is needed.
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Birch Petersen et al.
Human Reproduction, October 2015, Pages 2364-2375
Study question: To what extent does oral contraception (OC) impair ovarian reserve parameters in women who seek fertility assessment and counselling to get advice on whether their remaining reproductive lifespan is reduced?
Study design, size, duration: A cross-sectional study of 887 women aged 19–46 attending the Fertility Assessment and Counselling Clinic (FACC) from 2011 to 2014 comparing ovarian reserve parameters in OC users with non-OC users.
Main results and the role of chance: Of the 887 women, 244 (27.5%) used OC. In a linear regression analyses adjusted for age, ovarian volume was 50% lower (95% CI 45.1–53.7%), AMH was 19% lower (95% CI 9.1–29.3%), and AFC was 18% lower (95% CI 11.2–24.8%) in OC users compared with non-users. Comparison of AMH at values of <10 pmol/l OC was found to have a significant negative influence on AMH (OR 1.6, 95% CI 1.1; 2.4, P = 0.03). Furthermore, we found a significant decrease in antral follicles sized 5–7 mm (P < 0.001) and antral follicles sized 8–10 mm (P < 0.001) but an increase in antral follicles sized 2–4 mm (P = 0.008) among OC users. The two groups (OC users versus non-users) were comparable regarding age, BMI, smoking and maternal age at menopause.
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Abortion Legalization, Sex Selection, and Female University Enrollment in Taiwan
Priti Kalsi
Economic Development and Cultural Change, October 2015, Pages 163-185
Abstract:
Increasing access to sex-selective abortions in societies with a male preference should, theoretically, increase the average level of investments and care provided for girls who are not aborted. Existing literature finds that higher birth order sex selection increased after the legalization of abortion in Taiwan. This research presents evidence that the legalization of abortion in Taiwan improved the average rate of university attendance for girls born at higher birth orders where sex selection is most common. Specifically, I find that girls born at higher birth orders after the legalization of abortion are on average more likely to attend a university by approximately 4.5 percentage points. Moreover, a similar improvement in university attendance rates for higher birth order boys is not found. Heterogeneous results indicate that families with a relatively lower socioeconomic status are likely driving the results. The findings in this analysis are robust to several specifications, and they extend existing literature by providing evidence of the substitution hypothesis for a later-life economic outcome.
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Medicaid Reimbursement, Prenatal Care and Infant Health
Lyudmyla Sonchak
Journal of Health Economics, December 2015, Pages 10–24
Abstract:
This paper evaluates the impact of state-level Medicaid reimbursement rates for obstetric care on prenatal care utilization across demographic groups. It also uses these rates as an instrumental variable to assess the importance of prenatal care on birth weight. The analysis is conducted using a unique dataset of Medicaid reimbursement rates and 2001-2010 Vital Statistics Natality data. Conditional on county fixed effects, the study finds a modest, but statistically significant positive relationship between Medicaid reimbursement rates and the number of prenatal visits obtained by pregnant women. Additionally, higher rates are associated with an increase in the probability of obtaining adequate care, as well as a reduction in the incidence of going without any prenatal care. However, the effect of an additional prenatal visit on birth weight is virtually zero for black disadvantaged mothers, while an additional visit yields a substantial increase in birth weight of over 20 grams for white disadvantaged mothers.
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Louise Rohrbach et al.
Journal of Adolescent Health, October 2015, Pages 399–406
Purpose: The purpose of this study was to evaluate the impact of a rights-based sexuality education curriculum on adolescents' sexual health behaviors and psychosocial outcomes 1 year after participation.
Methods: Within 10 urban high schools, ninth-grade classrooms were randomized to receive a rights-based curriculum or a basic sex education (control) curriculum. The intervention was delivered across two school years (2011–2012, 2012–2013). Surveys were completed by 1,447 students at pretest and 1-year follow-up. Multilevel analyses examined curriculum effects on behavioral and psychosocial outcomes, including four primary outcomes: pregnancy risk, sexually transmitted infection risk, multiple sexual partners, and use of sexual health services.
Results: Students receiving the rights-based curriculum had higher scores than control curriculum students on six of nine psychosocial outcomes, including sexual health knowledge, attitudes about relationship rights, partner communication, protection self-efficacy, access to health information, and awareness of sexual health services. These students also were more likely to report use of sexual health services (odds ratio, 1.37; 95% confidence interval, 1.05–1.78) and more likely to be carrying a condom (odds ratio, 1.97; 95% confidence interval, 1.39–2.80) relative to those receiving the control curriculum. No effects were found for other sexual health behaviors, possibly because of low prevalence of sexual activity in the sample.
Conclusions: The curriculum had significant, positive effects on psychosocial and some behavioral outcomes 1 year later, but it might not be sufficient to change future sexual behaviors among younger adolescents, most of whom are not yet sexually active. Booster education sessions might be required throughout adolescence as youth initiate sexual relationships.
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Jason Feinberg et al.
International Journal of Epidemiology, August 2015, Pages 1199-1210
Objectives: Here we tested for the relationship of paternal sperm DNA methylation with autism risk in offspring, examining an enriched-risk cohort of fathers of autistic children.
Methods: We examined genome-wide DNA methylation (DNAm) in paternal semen biosamples obtained from an autism spectrum disorder (ASD) enriched-risk pregnancy cohort, the Early Autism Risk Longitudinal Investigation (EARLI) cohort, to estimate associations between sperm DNAm and prospective ASD development, using a 12-month ASD symptoms assessment, the Autism Observation Scale for Infants (AOSI). We analysed methylation data from 44 sperm samples run on the CHARM 3.0 array, which contains over 4 million probes (over 7 million CpG sites), including 30 samples also run on the Illumina Infinium HumanMethylation450 (450K) BeadChip platform (∼485 000 CpG sites). We also examined associated regions in an independent sample of post-mortem human brain ASD and control samples for which Illumina 450K DNA methylation data were available.
Results: Using region-based statistical approaches, we identified 193 differentially methylated regions (DMRs) in paternal sperm with a family-wise empirical P-value [family-wise error rate (FWER)] <0.05 associated with performance on the Autism Observational Scale for Infants (AOSI) at 12 months of age in offspring. The DMRs clustered near genes involved in developmental processes, including many genes in the SNORD family, within the Prader-Willi syndrome gene cluster. These results were consistent among the 75 probes on the Illumina 450K array that cover AOSI-associated DMRs from CHARM. Further, 18 of 75 (24%) 450K array probes showed consistent differences in the cerebellums of autistic individuals compared with controls.
Conclusions: These data suggest that epigenetic differences in paternal sperm may contribute to autism risk in offspring, and provide evidence that directionally consistent, potentially related epigenetic mechanisms may be operating in the cerebellum of individuals with autism.
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Tierney Lorenz, Gregory Demas & Julia Heiman
Physiology & Behavior, December 2015, Pages 92–98
Abstract:
Several studies have documented shifts in humoral immune parameters (e.g., immunoglobulins) across the menstrual cycle in healthy women. It is thought that these shifts may reflect dynamic balancing between reproduction and pathogen defense, as certain aspects of humoral immunity may disrupt conception and may be temporarily downregulated at ovulation. If so, one could expect maximal cycle-related shifts of humoral immunity in individuals invested in reproduction – that is, women who are currently sexually active – and less pronounced shifts in women who are not reproductively active (i.e., abstinent). We investigated the interaction of sexual activity, menstrual cycle phase, and humoral immunity in a sample of 32 healthy premenopausal women (15 sexually active, 17 abstinent). Participants provided saliva samples during their menses, follicular phase, ovulation (as indicated by urine test for LH surge), and luteal phase, from which IgA was assayed. Participants also provided blood samples at menses and ovulation, from which IgG was assayed. Sexually active participants provided records of their frequency of sexual activity as well as condom use. At ovulation, sexually active women had higher IgG than abstinent women (d = 0.77), with women reporting regular condom use showing larger effects (d = 0.63) than women reporting no condom use (d = 0.11). Frequency of sexual activity predicted changes in IgA (Cohen's f2 = 0.25), with women reporting high frequency of sexual activity showing a decrease in IgA at ovulation, while women reporting low frequency or no sexual activity showing an increase in IgA at ovulation. Taken together, these findings support the hypothesis that shifts in humoral immunity across the menstrual cycle are associated with reproductive effort, and could contribute to the mechanisms by which women's physiology navigates tradeoffs between reproduction and immunity.
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Gender Ratio under China's Two-Child Policy
Bing Xu & Maxwell Pak
Journal of Economic Behavior & Organization, November 2015, Pages 289–307
Abstract:
China's one-child policy has often been criticized for exacerbating its gender imbalance. Although such criticism implies that the gender imbalance should improve significantly once the one-child policy is removed, experiences of other countries with similar gender imbalance and no mandated fertility limit suggest that this conclusion should not be accepted without closer examination. Consequently, this paper examines the effects of allowing parents to have two children on the gender ratio. Specifically, we build a model of parental decision-making, in which parents choose between letting nature decide the gender of their child and manipulating the birth process to increase the likelihood of obtaining a son, and identify the optimal behaviors in this framework. We investigate the equilibrium level of gender imbalance under both the one-child and the two-child policy settings and show through a series of examples that the gender imbalance need not improve under the two-child policy.