Family Structure, Early Sexual Behavior, and Premarital Births

In this paper, we argue that entry into first sexual intercourse is a key process mediating the effects of family structure on premarital childbearing. We explicate three ways in which onset of sexual activity can mediate effects of family structure on premarital first births. First, the gross association between family structure and premarital birth risks may be due entirely to the effect of family structure on age at first intercourse. Second, the earlier the age at first intercourse, the longer the duration of exposure to the risk of a premarital first birth. Third, an early age at first intercourse may proxy unmeasured individual characteristics correlated with age at onset but uncorrelated with other variables in the model. We develop methods to assess such mediating effects and analyze data from two sources, the 1979-93 National Longitudinal Survey of Youth and the 1988 National Survey of Family Growth. We find that age at first intercourse partially mediates the effect on premarital birth risks of both snapshot measures of family structure at age 14 and a time-varying measure of the number of family transitions, but that significant effects of these variables remain net of age at first intercourse. Delaying age at intercourse by one year reduces the cumulative relative risk of a premarital first birth by a similar amount for both white and black women. For black women, the magnitude of this effect is roughly the same as that of residing in a mother-only family at age 14.

2000-15 Taxes and Marriage: A Two-Sided Search Analysis

Fil: Chade, Héctor. Universidad de San Andrés. Departamento de Economía; Argentina.Fil: Ventura, Gustavo. Universidad de San Andrés. Departamento de Economía; Argentina

Repartnering: the relevance of parenthood and gender to cohabitation and remarriage among the formerly married

This paper is an exploratory analysis of the impact of current and anticipated parenthood on cohabitation and remarriage among those formerly living in marriage-type relationships. The focus on children is embedded within a broader analysis of repartnering which takes account of other factors, including gender. Quantitative and qualitative analyses are used, with a multivariate analysis of repartnering patterns, using data from the General Household Survey, being complementedby in-depth interview data examining the attitudes of the formerly married to future relationships. The paper demonstrates that parenthood has a statistically significant effect on the likelihood of formerly married women repartnering, with a higher number of children being associated with a lower probability of repartnering. The presence of children can work against repartnering in a variety of ways. Children place demands on their parents and can deter or object to potential partners. Parents may see their parental role as more important than, and a barrier to, new relationships. However, mothers are typically looking for partners for themselves rather than fathers for their children. Among formerly married people without children, the desire to become a parent encourages repartnering. The paper concludes that parenthood should be a key consideration in analyses of repartnering

The Economic Resource Receipt of New Mothers

U.S. federal policies do not provide a universal social safety net of economic support for women during pregnancy or the immediate postpartum period but assume that employment and/or marriage will protect families from poverty. Yet even mothers with considerable human and marital capital may experience disruptions in employment, earnings, and family socioeconomic status postbirth. We use the National Survey of Families and Households to examine the economic resources that mothers with children ages 2 and younger receive postbirth, including employment, spouses, extended family and social network support, and public assistance. Results show that many new mothers receive resources postbirth. Marriage or postbirth employment does not protect new mothers and their families from poverty, but education, race, and the receipt of economic supports from social networks do

The involvement of Pseudomonas putida in basidiome initiation of the cultivated mushroom Agaricus bisporus.

The involvement of pseudomonads In the process of basidiome initiation of the cultivated mushroom Agaricus bisporus was investigated. Pseudomonads used throughout the study were identified and Pseudomonas putida was shown to be responsible for initiating basidiome morphogenesis. The prodigious morphogenetical capabilities of a single P. putida and P. tolaasii colony was demonstrated and the production of rough colonial forms in peat casing soil was observed. Rough colonial forms of P. putida were found to be capable of promoting basidiome initiation. Cells of the rough colonial forms were better able to withstand nutrient limited conditions, were more resistant to UV light, produced greater amounts of siderophore and respired at a faster rate than the smooth colonial variants which indicates that they are stress tolerant forms. P. putida and P. tolaasii were shown to be positively attracted toward exudates of mushroom mycelium and adherence of these bacteria to hyphae was observed. Quantitative adherence studies, in conjunction with electron microscopy, revealed the ability of P. putida and P. tolaasii cells to adhere rapidly and firmly to hyphae. Differences in the chemotactic and adhesive abilities of smooth and rough colonial forms were observed. A new medium for the growth of A. bisporus was developed and a strain of A. bitorquis W19 which produces primordia in vitro, when grown in association with basidiome stimulatory pseudomonads, was used as a model system for assaying the effect of bacteria on basidiome initiation. Activated charcoal was shown to replace the effects of P. putida and fruit body initiation did not to occur in response to nutrient limitation. Non-living P. putida failed to promote basidiome initiation and iron, and Iron chelating agents did not stimulate fruiting: During the preliminary phase of the interaction between P. putida and A. bisporus, the bacterium was shown to markedly affect hyphal growth, colony morphology and the allocation of resources to the mycelium. Mutants of P. putida defective in their ability to promote basidiome initiation were produced by transposon Tn5 and UV light mutagenesis. The majority of these mutants were defective in their ability to uptake the ferric-siderophore complex implicating the involvement of iron regulated, membrane bound protein porins in the process of fruit body initiation. It is thought that the mushroom mycelium produces a 'self-Inhibitory-compound' which prevents basidiome morphogenesis until levels of this compound are reduced to below a threshold concentration. P. putida is thought facilitate this by Importing the Inhibitory substance into the cell, via the membrane bound protein porins, where it Is subsequently metabolized. A gene cloning and mapping system was developed In P. putida using RP4::mini-Mu. This plasmid was shown to promote transfer of auxotrophic markers in both homologous and heterologous matings and its potential as a gene cloning and mapping system in this organism was demonstrated

Levels and Correlates of Non-Adherence to WHO Recommended Inter-Birth Intervals in Rufiji, Tanzania.

Poorly spaced pregnancies have been documented worldwide to result in adverse maternal and child health outcomes. The World Health Organization (WHO) recommends a minimum inter-birth interval of 33 months between two consecutive live births in order to reduce the risk of adverse maternal and child health outcomes. However, birth spacing practices in many developing countries, including Tanzania, remain scantly addressed. METHODS: Longitudinal data collected in the Rufiji Health and Demographic Surveillance System (HDSS) from January 1999 to December 2010 were analyzed to investigate birth spacing practices among women of childbearing age. The outcome variable, non-adherence to the minimum inter-birth interval, constituted all inter-birth intervals <33 months long. Inter-birth intervals >=33 months long were considered to be adherent to the recommendation. Chi-Square was used as a test of association between non-adherence and each of the explanatory variables. Factors affecting non-adherence were identified using a multilevel logistic model. Data analysis was conducted using STATA (11) statistical software. RESULTS: A total of 15,373 inter-birth intervals were recorded from 8,980 women aged 15--49 years in Rufiji district over the follow-up period of 11 years. The median inter-birth interval was 33.4 months. Of the 15,373 inter-birth intervals, 48.4% were below the WHO recommended minimum length of 33 months between two live births. Non-adherence was associated with younger maternal age, low maternal education, multiple births of the preceding pregnancy, non-health facility delivery of the preceding birth, being an in-migrant resident, multi-parity and being married. CONCLUSION: Generally, one in every two inter-birth intervals among 15--49 year-old women in Rufiji district is poorly spaced, with significant variations by socio-demographic and behavioral characteristics of mothers and newborns. Maternal, newborn and child health services should be improved with a special emphasis on community- and health facility-based optimum birth spacing education in order to enhance health outcomes of mothers and their babies, especially in rural settings

Fertility, Living Arrangements, Care and Mobility

There are four main interconnecting themes around which the contributions in this book are based. This introductory chapter aims to establish the broad context for the chapters that follow by discussing each of the themes. It does so by setting these themes within the overarching demographic challenge of the twenty-first century – demographic ageing. Each chapter is introduced in the context of the specific theme to which it primarily relates and there is a summary of the data sets used by the contributors to illustrate the wide range of cross-sectional and longitudinal data analysed

“Swapping” Families: Serial Parenting and Economic Support for Children

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71408/1/j.1741-3737.2000.00111.x.pd