Family Formation

Kevin Lewis

March 20, 2022

Continuity and Change in U.S. Children's Family Composition, 1968–2017
Paula Fomby & David Johnson
Demography, forthcoming

We document changes in U.S. children's family household composition from 1968 to 2017 with regard to the number and types of kin that children lived with and the frequency of family members' household entrances and departures. Data are from the U.S. Panel Study of Income Dynamics (N = 30,412). Children experienced three decades of increasing instability and diversification in household membership, arriving at a state of “stable complexity” in the most recent decade. Stable complexity is distinguished by a decline in the number of coresident parents; a higher number of stepparents, grandparents, and other relatives in children's households; and less turnover in household membership compared with prior decades, including fewer sibling departures. College-educated households with children were consistently the most stable and least diverse. On several dimensions, household composition has become increasingly similar for non-Hispanic Black and White children. Children in Hispanic households are distinct in having larger family sizes and more expected household entrances and departures by coresident kin. 

A Meta-Analysis of the Effects of Wilderness Therapy on Delinquent Behaviors Among Youth
Natalie Beck & Jennifer Wong
Criminal Justice and Behavior, forthcoming

The purpose of the present meta-analysis was to determine the effectiveness of wilderness therapy in addressing youth delinquency. A systematic review of the literature was conducted using 27 electronic databases and numerous gray literature sources, surveying literature published from 1990 to 2020. The search identified 189 potential studies for inclusion, resulting in a final study pool of 11 studies contributing 14 effect sizes from a total sample of 1,874 treatment youths. Both self-reported delinquency and caregiver-reported delinquency were examined using separate random-effects models. Pooled analyses yielded large, positive, and significant effects of 0.832 and 1.054 respectively, indicating that wilderness therapy is potentially an effective tool for addressing delinquent behaviors among youth. Limitations of the study include a lack of moderator analyses due to the small sample sizes. Wilderness therapy is a promising form of diversion programming and further investigation into this treatment modality is warranted. 

Impact of Comprehensive State Insurance Mandates on In-Vitro Fertilization Utilization, Embryo Transfer Practices, and Outcomes in the United States
Benjamin Peipert et al.
American Journal of Obstetrics and Gynecology, forthcoming

Study Design:
We conducted a retrospective cohort study of IVF cycles reported by the 2018 Centers for Disease Control Assisted Reproductive Technology Fertility Clinic Success Rates Report in the United States. IVF cycles were stratified according to state mandate: comprehensive (providing coverage for IVF with minimal restrictions) and non-comprehensive. US Census estimates for 2018 were used to calculate the number of reproductive-age women in each state. Outcomes of interest (stratified by state mandate status) included utilization rate of IVF per 1,000 women ages 25 to 44, live birth rate, multiple birth rate, number of embryo transfer procedures (overall and subdivided for fresh vs. frozen cycles), and percent of transfers performed with frozen embryos. Additional sub-analyses were performed stratifying outcomes by patient age group.

In 2018, 134,997 IVF cycles from 456 clinics were reported. Six states had comprehensive mandates; 32,029 and 102,968 cycles were performed in states with and without comprehensive IVF mandates, respectively. IVF utilization in states with comprehensive mandates was 132% higher than non-comprehensive states after age adjustment; increased utilization was observed regardless of age stratification. Live birth rate per cycle was significantly higher in states with comprehensive mandates (35.4% vs 33.4%, p<0.001), especially among older age groups. Multiple birth rate as a percentage of all births was significantly lower in states with comprehensive mandates (10.2% vs 13.8%, p<0.001), especially among younger patients. Mean number of embryos per transfer was significantly lower in states with comprehensive mandates (1.30 vs 1.36, p<0.001). Significantly fewer frozen transfers were performed as a percentage of all embryo transfers in states with comprehensive mandates (66.1% vs 76.3%, p<0.001). Among fresh embryo transfers, significantly fewer embryos were transferred in comprehensive states among all patients (1.55 vs. 1.67, p<0.001). 

Chains of Adversity: The Time-Varying Consequences of Paternal Incarceration for Adolescent Behavior
Kristin Turney
Journal of Quantitative Criminology, March 2022, Pages 159–196

I use six waves of data from the Fragile Families and Child Wellbeing Study, a cohort of children born around the turn of the twenty-first century, and inverse probability of treatment weighting models to estimate the time-varying relationship between paternal incarceration and adolescent behavior problems and the mechanisms underlying this relationship.

Results document three main findings. First, adolescents exposed to paternal incarceration at any point in the life course have more behavior problems than their counterparts not exposed to paternal incarceration. Second, exposure to paternal incarceration during early childhood, but not during middle childhood or early adolescence, is positively associated with behavior problems. Third, this relationship is partially explained by family adversities stemming from paternal incarceration. 

Interpregnancy interval and the risk of oppositional defiant disorder in offspring
Berihun Assefa Dachew et al.
Development and Psychopathology, forthcoming

The study aimed to investigate the association between interpregnancy interval (IPI) and parent-reported oppositional defiant disorder (ODD) in offspring at 7 and 10 years of age. We used data from the Avon Longitudinal Study of Parents and Children (ALSPAC), an ongoing population-based longitudinal study based in Bristol, United Kingdom (UK). Data included in the analysis consisted of more than 3200 mothers and their singleton children. The association between IPI and ODD was determined using a series of log-binomial regression analyses. We found that children of mothers with short IPI (<6 months) were 2.4 times as likely to have a diagnosis of ODD at 7 and 10 years compared to mothers with IPI of 18–23 months (RR = 2.45; 95%CI: 1.24–4.81 and RR = 2.40; 95% CI: 1.08–5.33), respectively. We found no evidence of associations between other IPI categories and risk of ODD in offspring in both age groups. Adjustment for a wide range of confounders, including maternal mental health, and comorbid ADHD did not alter the findings. This study suggests that the risk of ODD is higher among children born following short IPI (<6 months). Future large prospective studies are needed to elucidate the mechanisms explaining this association. 

Disgust sensitivity is negatively associated with immune system activity in early pregnancy: Direct support for the Compensatory Prophylaxis Hypothesis
Šárka Kaňková et al.
Evolution and Human Behavior, forthcoming

According to the Compensatory Prophylaxis Hypothesis (CPH), disgust may be considered a part of the behavioral immune system, adjusting as a function of immunocompetence. Early pregnancy involves modulation of a complex network of various immune-related factors, but only a few studies so far have focused on disgust sensitivity in pregnant women in the context of the CPH. This study aimed to examine associations between disgust sensitivity and immune activity indices, cytokine levels, and white blood cell (WBC) count in pregnant women. The sample included 78 women in the 1st trimester of pregnancy. Higher disgust sensitivity (Disgust Scale-Revised; DS-R) was significantly associated with decreased levels of IL-1β, IL-2 IL-4, IL-7, IL-17, Eotaxin, MCP-1 (MCAF), and RANTES in blood serum. This model explained 17.5% of the total DS-R score variability. Using the DS-R subscales, the Contamination disgust was significantly associated with levels of FGF basic, IFN-γ, IL-1β, IL-2, IL-4, IL-7, IL-17A, G-CSF, MCP-1 (MCAF), MIP-1α, PDGF-BB, and RANTES, and the Core disgust was significantly associated with levels of IL-1β, IL-2, IL-4, IL-7, IL-17A, Eotaxin, G-CSF, IP-10, MCP-1 (MCAF), PDGF-BB, and TNF-α. Disgust sensitivity was not associated with WBC count. Disgust may reflect and compensate for insufficient immune adaptation in early pregnancy, suggesting the potential clinical significance of this common prenatal symptom. 

Maternal lactational investment is higher for sons in chimpanzees
Iulia Bădescu et al.
Behavioral Ecology and Sociobiology, March 2022

Maternal lactational investment can affect female reproductive rates and offspring survival in mammals and can be biased towards infants of one sex. We compared estimates of lactation effort among mothers, assessed as their potential milk contribution to age-specific infant diets (mother-infant differences in fecal stable nitrogen isotopes, δ15N), to the timing of weaning (infant age at last nursing bout) and to maternal inter-birth interval lengths for male and female infant chimpanzees (Pan troglodytes) at Ngogo, Uganda. Infant males had greater proportions of milk in their age-specific diets, indicated by higher mother-infant differences in δ15N (Generalized Estimating Equation, GEE: p < 0.01). This may mean that mothers of sons showed greater lactation effort than mothers of daughters. Infant males stopped nursing at older ages than infant females (Kaplan–Meier product limit estimate, Breslow estimator: p < 0.05). Mothers of sons showed longer interbirth intervals than mothers of daughters (GEE: p < 0.01). All three measures indicated maternal lactational investment was higher for sons. Male infants may cost mothers more to ensure infant survival than female infants because males are more vulnerable and/or because maternal genetic returns on investment are greater for sons than daughters, as male philopatry means that chimpanzee mothers can have more influence on the reproductive success of sons. Chimpanzee females may trade off growth-related benefits of high lactational investment in male offspring against reduced reproductive rates.


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