FAMILY AND FERTILITY

A report from National Institute of Health

Traditionally, fertility and family have been treated as separate research areas within the DBSB program, and within population research in general. In 1998, the Branch began an effort to replace the separate programs with a combined focus that highlights the interrelationships among creating partnerships, having children, and raising them. This new emphasis parallels demographic trends that have challenged traditional assumptions about what constitutes a family, and about what events mark the formation of a family. In recent decades, DBSB grantees have documented shifts in fertility and marriage patterns, and increases in nonmarital cohabitation and childbearing. Their research has examined families formed outside of marriage, through remarriage, and through cohabiting relationships-families that were previously the subject of little research.

• Marriage
• Divorce
• Cohabitation Outside Marriage
• Nonmarital Childbearing
• Fertility: Trends, Timing, and Motivation
• Public Policy and Family Formation
• Male Fertility and Fatherhood
• Work, Families, and Child Care
• Fertility, Family, and the Well-Being of Children and Adults

Marriage

One of the key demographic changes contributing to family change has been the delay in age at marriage. In 1960, women first married at a median age of 20.1, and men at 22.5. By mid-2000, these ages had risen to 25.1 and 26.8, respectively. The trend toward delayed or foregone marriage has been especially marked among African American women. In the mid-1990s, 80 percent of white women had married by age 30, compared with only 45 percent of African American women. Among new, unmarried parents, African Americans were also significantly less likely to marry than Hispanics or whites. This large racial gap in marriage has been attributed to the dearth of "marriageable" men in poor African American populations, owing to stagnation in economic opportunities, and to high rates of incarceration.

Research has also shown that earnings of both men and women are important in explaining marriage trends and rates in the United States. Increased wage rates among highly educated women were implicated in the decline in marriage for this group, while decreased wage rates among poorly educated males were implicated in the marriage decline for poorly educated women. Women's earnings have become a more powerful factor in marriage than they were in the past. In addition, DBSB-supported research found that, among new parents who were unmarried at the time of their child's birth, couples were more likely to be married a year later if the father had a high earning capacity, if the couple's earning capacity was high, or if the mother's actual wages were high.

Research has also implicated changing gender roles, attitudes, and values in changing marriage patterns. Attitudes and beliefs toward marriage and gender roles, as well as religiosity and relationship quality were important in determining which unwed parents would marry within 12 months of their child's birth. Differences in human capital, attitudes, and relationship assessments also made unique and significant contributions to explaining differences in marriage among new unwed parents.

Given continuing changes in the economy, shifts in attitudes and values in the society, and trends in educational attainment, what is the future likely to hold? A recent DBSB-funded study revealed that a new socioeconomic pattern has emerged with respect to first marriages. Whereas, in the past, college graduates were less likely to marry than women with fewer years of schooling, recent college graduates are now expected to marry at higher levels, despite a later entry into first marriage. This educational crossover, which was observed for both African American and white women in recent cohorts, suggests that marriage is increasingly becoming a province of the most educated, a trend that could become a new source of inequality for future generations.

Divorce

The divorce rate reached its peak in 1980, and has declined slightly since then. NSFG data on marriage, divorce, and remarriage in the United States revealed that 43 percent of first marriages end in separation or divorce within 15 years. As is the case with marriage, economic factors are important in explaining divorce. Wives' employment, measured as the number of hours wives worked, did not affect the probability of divorce during the 1970s or early 1980s, but increased the risk of divorce during the late 1980s and early 1990s. This study also found that the number of hours a wife worked became more important as a predictor of divorce as length of marriage increased. Another study found that the higher rates of divorce in disadvantaged neighborhoods were explained entirely by the low incomes of husbands in these groups.

Cohabitation Outside Marriage

While marriage rates have been declining, cohabitation outside marriage has emerged as an antecedent or alternative to marriage. The NSFH has documented the growth of cohabitation since 1970, showing that: (1) increasing proportions of the population have lived in a cohabiting relationship at some point in time; (2) the proportion of current unions that are unmarried cohabitations has increased dramatically, nearly doubling in the 25 to 39 age range; and (3) the greatest relative increases in cohabitation have occurred among high school graduates.

The role cohabitation plays in changing marriage and fertility patterns needs clarification, but such a clarification will be difficult until researchers are able to better understand the various meanings that cohabitation may have for different couples. The DBSB is currently funding two qualitative research projects to examine the diverse circumstances of cohabiters, and to shed light on exactly how cohabitation fits into family life.

Nonmarital Childbearing

Increases in cohabitation have contributed to another dramatic change-the increased proportion of births that occur to unmarried couples. NSFG data revealed that, by increasing the chance of both planned and unplanned births among unmarried women, increased rates of cohabitation accounted for almost all of the increase in unmarried childbearing between 1980 and 1984, and between 1990 and 1994. The proportion of nonmarital births occurring to cohabiting couples increased from 29 percent to 39 percent during these periods.

Increases in nonmarital childbearing have been particularly striking among first births. First births outside of marriage continue to be largely concentrated in the teen years, while first births within marriage have become increasingly concentrated among women in their mid- and late-twenties. For the last 25 years, the average age at which unmarried women gave birth for the first time has been similar for African American and white women. However, the fertility behavior of married and unmarried women has become increasingly different. Once differences in marital status are taken into account, racial differences are of declining significance in explaining fertility patterns.

A woman's relationship status at first birth is highly predictive of her status at subsequent births. Marital first births are overwhelmingly followed by marital second births, cohabiting first births by cohabiting second births, and single first births by single second births.

Fertility: Trends, Timing, and Motivation

Within the United States, the total fertility rate has remained remarkably stable since the early 1970s. However, the average age at first birth increased across the population during the 1970s and 1980s. The shift to delayed childbearing has been most dramatic among well-educated women, most likely because of the increased access of these women to career-type jobs. In such jobs, the steep costs of leaving the work force to raise children may motivate women to delay childbearing until they have established their careers and are able to afford adequate child care.

Rates of teen childbearing increased sharply during the late 1980s, but then declined rapidly during the 1990s, to reach an all-time low in 2001. Reasons for these sharp declines are complex. NSFG data indicate that both better contraception, and increased sexual abstinence have played important roles in the decline. Improvements in the socioeconomic backgrounds of young women over time have also lessened the risk of teen motherhood; however, changes in family structure of origin have increased the risk of teen motherhood.

Fertility trends have also been affected by shifts in social norms and economic circumstances. One DBSB grantee found that, using behavioral genetic models, the proportion of variation in fertility attributable to heredity changed over time. For instance, during times of increased reproductive choice, the influence of heredity in female fertility was increasingly important. The role of heredity also appeared to be more important in the onset of childbearing, than it was in total family size. Other research has suggested that societal changes in attitudes about gender inequality may affect fertility at higher parity levels. For example, during much of the 20th century, the gender of the first two children in the family influenced the likelihood of a third birth; parents with two children of the same sex were more likely to have a third child than were parents with one son and one daughter. However, since 1985, this effect has attenuated.

A DBSB grantee has proposed that the "social capital" value of children, defined as their value in creating new social ties and resources, may be a previously neglected motivation for fertility. Using NSFH data, this research suggested that fertility intentions were higher among individuals who viewed children as a means to greater connectivity to others, and to increased social rewards. Other research is underway to examine how the value of children affects fertility decisions among stepfamilies.

Public Policy and Family Formation

An increasing body of evidence suggests that marriage and fertility patterns are responsive to public policies that influence economic incentives or affect access to reproductive services. In each of the past 10 years, North Carolina's state funds that were intended to subsidize abortions for poor women for an entire year have been exhausted partway through the year. Investigators found that the interruptions in state funding had pervasive and substantial effects on fertility decisions, especially among young, unmarried, African American women. The research also found that women were more likely to carry pregnancies to term when funding was not available, thus increasing rates of childbearing among unmarried, young, African Americans.

Currently, the research literature is divided on whether the welfare system contributes to low marriage rates and high levels of nonmarital childbearing in low socioeconomic populations. To clarify the mixed results in this area, a DBSB-supported investigator is currently conducting a thorough analysis of the effects of welfare policy on nonmarital childbearing and marriage. Preliminary results from the Fragile Families and Child Well-Being Study showed that increased cash benefits did not increase the likelihood of marriage among new unmarried parents. However, effective child-support enforcement increased the odds that the couple would marry. The father's employment had an even greater effect on the odds of marriage.

Other researchers are using data from the Fragile Families and Child Well-Being Study to investigate whether policies intended to increase marriage will, if successful, also lift single-parent families out of poverty. Results have indicated that, although two incomes could lift many single-mother families out of poverty, 46 percent of unmarried parents would continue to earn below the federal poverty line, even if they were to marry.

Male Fertility and Fatherhood

In the late 1990s, as part of the federal Fatherhood Initiative, the DBSB participated in an interagency effort to review federal data and research on male fertility and fatherhood. This effort resulted in a report published by the Federal Forum on Child and Family Statistics titled, Nurturing Fatherhood: Improving Data and Research on Male Fertility, Family Formation, and Fatherhood. This report spurred a series of investments in research and data collection, including the development of a male survey within the NSFG, and the addition of fathering measures in several new studies of families and child development.

Some of the new research highlights the experience of fatherhood in the national population. New data from the Panel Study of Income Dynamics-Child Development Supplement (PSID-CDS) showed that fathers in intact families were spending an increased amount of their time with their children, particularly during the weekends. (See Sidebar for a description of this study.) Fathers' wages and work hours affected the amount of time they spent with their children during the weekdays, but not the weekends. This research also found that African American fathers, in general, were less involved in their children's lives than white fathers; Hispanic fathers were more involved than white fathers. Differences in styles of parenting among African American, white, and Hispanic fathers were explained, in part, by differences in economic circumstances, neighborhood contexts, gender role attitudes, and intergenerational experiences of fathering.

Other research based on NSFH data suggested that it was not the formation of a new union, but the responsibility for new children, particularly new biological children, that reduced the odds of fathers' frequent in-person contact with their non-resident children. Fathers also reduced their child-support payments to non-resident children, often informally, to accommodate the demands of new biological children. Improving non-custodial parents' control over and access to their children promoted child-support payment and improved outcomes for children. Similarly, joint legal custody resulted in higher child-support payments and better child outcomes.

Other research on fatherhood supported by the Branch has focused on economically disadvantaged populations. One group synthesized qualitative research that probed the experience of fatherhood for African Americans in low-income, urban communities. The study found that fatherhood, for this population, was an active, flexible relationship that evolved over time. Most men in these communities aspired to conventional work values, but their inability to find good and consistent employment decreased their potential to be involved parents and encouraged marginal relationships with partners and families. However, negotiations within families allowed fathers to tailor active roles in their children's lives, often substituting time and in-kind support for economic support.

The Fragile Families and Child Well-Being Study has helped to dispel the myth that fathers of babies born out-of-wedlock had no real interest in or contact with their children. Among unmarried women who gave birth, 83 percent reported that they were romantically involved with the baby's father, and 51 percent were living with the father. A majority of unmarried mothers believed that their chances of marrying the father of their children were "pretty good" or "almost certain." In addition, 83 percent of mothers indicated that the father contributed financially during the pregnancy. These findings, conveyed to congress as part of testimony given by the study's principal investigator, Dr. Sara McLanahan, have given rise to policy initiatives that seek to strengthen family relationships and produce healthy marriages among so-called fragile families.

Work, Families, and Child Care

Another important change affecting the family has been mothers' widespread participation in the labor force, which has resulted in increased use of non-parental child care while mothers are at work. Care provided by family and friends, home-based care, and other "informal" types of care have been prominent features of the child care revolution. Frequent changes in arrangements are typical, both as the children grow older, and as school-based alternatives increase.
DBSB grantees have pointed out the key role that child care plays in moderating the relationship between involvement in the labor force and fertility. If child care is affordable and accessible, increased participation of females in the labor force participation does not necessarily translate into reduced fertility levels. In fact, the income earned by working parents can facilitate family formation by supplying resources to pay for child care. A study recently funded by the DBSB will examine the effect of local variations in child care supply on the timing and level of fertility.

Policies that allow parents to spend time with and take care of their children when they are sick help parents juggle work and family responsibilities. Multivariate results indicated that parents who had either paid sick, or vacation, leave were five times more likely to care for their children when the children were sick. However, federal and state parental leave laws enacted in the 1990s have had no effect on fathers' leave-taking around the time of a child's birth, and have only slightly increased the frequency and length of mothers' unpaid leave for a child's birth.

Balancing work and family can be even more difficult for single parents and disadvantaged families, especially when health problems complicate family life. Research based on NLSY data indicated that mothers who had been on Aid to Families with Dependent Children (AFDC) were more likely to be caring for at least one child with a chronic health condition, compared with mothers who never received assistance. Poor parents coping with their own or their children's health limitations had far greater difficulty maintaining paid employment; having to care for a child with a health limitation increased a woman's probability of job loss by 33 percent. Further, disadvantaged women were less likely to have employment benefits that helped them take time off to care for children. Mothers who had been on AFDC were also less likely to have paid sick leave throughout their working careers, and were less likely to receive other paid leave or flex time.

Issues related to balancing work and family will grow in importance over the coming decades, as the service sector continues to grow, and as women are called upon to fill the jobs vacated by the retiring "baby boomers." At the request of the NICHD director, the DBSB is developing an initiative on work/family issues designed to create innovative approaches to improving the fit between family responsibilities and employer needs. The Branch has held a planning meeting and planned an inaugural conference in pursuit of advances in this research area.

Fertility, Family, and the Well-Being of Children and Adults

Events that form and reshape families have important economic, social, and psychological consequences for family members. In recent years, the DBSB has continued to support research on the consequences of early childbearing and divorce for both parents and children. This work has greatly expanded research on the consequences of family change for child well-being.

Unwanted pregnancies and births are associated with negative outcomes for both women and children. Women who had unwanted births were less likely to receive adequate prenatal care, were more likely to smoke during pregnancy, and were more likely to have babies whose health was compromised. Children born as a result of an unwanted pregnancy were also likely to experience poorer cognitive development, and to have lower self-esteem as adults. NLSY data suggested that the attitudes of both parents toward the pregnancy were important for the health of the pregnancy and child. Compared with pregnancies intended by both parents, those intended by the mother but not the father were more likely to be characterized by delayed prenatal care and maternal smoking; the resulting infants were more likely to be low birth weight and to not be breastfed.

A large body of research has documented the association between teen childbearing and a variety of adverse outcomes, including poverty and welfare dependency, low educational attainment, and poorer developmental outcomes for children; these results hold true even after statistically controlling for the disadvantaged backgrounds of teenage mothers. Recent research has shown that the effect of teen childbearing on high school completion has lessened. In fact, one recent study found that teen mothers were no less likely to obtain a high school degree, either a diploma or a graduate equivalency diploma, than if they delayed their childbearing until adulthood. However, the gap in postsecondary school attendance for teenage versus later child bearers widened substantially between the early 1960s and the early 1990s.

Further, a comparison of teenage mothers to women who delayed their first birth substantially (until age 30 or older) revealed strong differences in both high school completion, and postsecondary schooling. Differences in the circumstances of children born into families with differing levels of education are larger now than when most women had their babies in their late teens or early twenties.

Research has also addressed the social, economic, and developmental consequences of divorce for parents and children. Results have confirmed that divorce hurts women economically, although less so than is suggested by comparing the economic situation of divorced and married women; these comparisons are inflated by economic differences associated with the risk of divorce. Either remarrying or cohabiting with a new partner after divorce can restore income levels to pre-divorce levels, according to a study based on NLSY data. However, children's long-term economic stability depends on the mother's choice between cohabitation and marriage, and on the stability of the new relationship. Neither stable, nor unstable, cohabitations provided economic advantages to children compared to the mother remaining single; remarriage, and especially a stable remarriage, did provide these advantages.

Other studies based on NLSY data demonstrated that, while the experience of divorce had small adverse consequences on children's mental health and behavior well into adulthood, many of the problems experienced by children of divorce can be traced to conditions and characteristics that preceded the divorce. A recent study found that, for most outcomes, the effects of divorce on children were similar regardless of whether their parents divorced when they were children, or postponed the breakup of marriage until after the children were grown.

Effects of divorce were found in relationships with grandchildren as well. A divorce in the grandparent generation had negative effects on many aspects of grandparenting, especially for grandfathers and paternal grandparents. In part, these negative effects resulted from weaker bonds with and greater distance from grandchildren.

Divorce affects children, in part, by affecting parenting practices. Researchers analyzing mothers' and children's reports of parenting practices in the NSFH found that use of harsh discipline was greater among mothers whose relationships had dissolved, than among those in intact relationships. Another researcher demonstrated that marital dissolution triggered lower quality parent-child relationships, less positive orientations toward marriage, and more positive orientations toward divorce and premarital sex on the part of children. Among children whose parents separated during their adolescence, a researcher using Add Health Study data found that delinquency rates increased more dramatically after the separation if the child was close to his or her same-sex parent prior to the separation.

In addition, about two-fifths of all children spend some time in a cohabiting family. Because cohabiting relationships do not last as long as marriages, children in cohabiting families are more likely to experience family disruption. Researchers are now more fully investigating the links between cohabitation and child well-being. This focus is a challenging, but important, next step for research in this area.

For more information please visit National Institute of Child, Health & Human Development website.