Through the first child’s ninth birthday, the program continued to increase the interval between the births of first and second children, reduced the cumulative number of subsequent live births per year, increased the stability of mothers’ relationships with their partners, and reduced women’s use of welfare and food stamps. The impact of the program on cumulative subsequent live births was limited to mothers with initially higher levels of psychological resources, and its impact on use of welfare was concentrated in the 0- to 6-year interval after birth of the first child. Through the first 3 years of elementary school, the program improved the academic achievement of children who were born to mothers with low psychological resources, and as a trend, it reduced the rate of infant and childhood mortality among first-born children during the 9-year period after birth of the first child.
Although the statistical significance of the treatment difference in infant and childhood mortality is only marginal, the causes of death are noteworthy. The 1 death in the nurse-visited group was attributed to a chromosomal anomaly. Nine of the 10 deaths in the control group were either associated with preterm delivery or attributable to sudden infant death syndrome or injury. This raises the possibility that when focused on highly impoverished populations such as that sampled in this trial, the program may be able to prevent a range of adverse child outcomes, including death.
The impact of the program on duration of partner relationships and, as a trend, involvement of the child’s biological father in the family is consistent with corresponding effects observed on stability of partner relationships in the Elmira program at child age 329
and marriage at child age 15.30
This consistency of effects lends validity to each of these findings.
The impact of the program on fertility-related outcomes among mothers with higher psychological resources is consistent with findings reported previously,8,11,12
which we have attributed to mothers’ developing the wherewithal to envision and secure employment11
and manage simultaneously the demands of being an employee and providing competent care for their children.8
One crucial factor contributing to economic self-sufficiency is pregnancy planning. The lower resource mothers who were visited by nurses, we hypothesize, had fewer personal resources to enable them to manage both roles well and therefore chose to focus their limited resources on the care of their children rather than attempting to make it in the world of work.
Without help, low-resource mothers are at greater risk for having difficulty caring competently for their children, who in turn are at risk for a host of problems. We believe that nurse-visited low-resource mothers chose to focus their resources on the care and protection of their children, and this explains why they were particularly successful, compared with their control-group counterparts, in managing the care of their firstborn children, as reflected in their children’s having fewer injuries through age 2 and better cognition, arithmetic achievement, adjustment at age 6, and academic achievement in grades 1 to 3.7,8,11,12
It is possible that the reduction in use of AFDC/TANF and food stamps observed during the 9-year period after birth of the first child for the entire sample may be explained at least in part by the nurse-visited women’s increased involvement with the first child’s biological father and the stability of partnered relationships, given that their partners were frequently employed and most likely brought additional financial resources to the household.
In 1996, the US welfare reform act went into effect,31
limiting women’s lifetime use of public assistance (TANF). Although this may partially explain the gradually diminished impact of the program on use of welfare over time, Tennessee has had a waiver that exempts it from invoking all of the TANF restrictions on use of welfare.32
Moreover, it is important to note that Medic-aid in Tennessee covered pregnant women up to 185% of poverty during the most recent phase of follow-up and paid for 37% of all births in 2000.33
These high rates of coverage probably account for the failure of the program to reduce use of Medicaid overall in this highly disadvantaged population.
At the 6-year follow-up of this sample, we reported that nurse-visited mothers had placed their children in some form of structured child care or preschool before kindergarten.8
To determine the degree to which the program effects reported here on academic achievement were accounted for by this increased use of child care and preschool, we repeated the analysis of academic achievement outcomes controlling for enrollment in preschool programs. The impact of the program on the achievement scores and GPAs of children who were born to low-resource mothers was virtually unchanged by this statistical control. Therefore, the program impact on children’s achievement observed in this trial is independent of the nurse-visited children’s higher enrollment in preschool programs.
These findings are encouraging but must be interpreted in light of their limitations. The first is that we did not have funds to conduct direct assessments of the children at this phase of follow-up and therefore had to rely on maternal report and children’s school records for information on child functioning. Assessing child welfare records might have increased our insight into program impact, but these records are particularly unreliable in Tennessee before a legal settlement that was reached in 2001 to improve the state’s child welfare infrastructure, including the establishment and maintenance of a valid computerized information system.34
Moreover, official records pick up only a very small fraction of actual maltreatment.35
The second limitation is that some of the outcomes are not independent of one another. We have reported interrelated outcomes to provide the reader with a full understanding of the range of program effects.
Finally, the program impact on childhood mortality does not reach conventional levels of statistical significance. The program–control difference in mortality, however, is attributable to potentially preventable causes, and the finding is consistent with earlier program effects on injuries and qualities of parental care,12
as well as a recent evaluation of a statewide replication of the NFP in Oklahoma, which found significantly fewer neonatal deaths and preterm deliveries on the part of intervention infants who were born to unmarried mothers without obstetric complications compared with propensity-matched control subjects.36