Research has shown that about 1 out of every 10 people in the United States suffer from depression, with women being affected at about twice the rate as men (National Institutes of Mental Health, 2008; Blehar & Oren, 1997). Of particular concern is the negative impact that depression has on parenting practices and behavior causing impairments in both the mother’s and children’s health and development. A lack of social support and elevated rates of stress increase the risk of depression among new mothers and likely contribute to negative parenting practices such as neglect (Lesser, Anderson, & Koniak-Griffin, 1998; East & Felice, 1990). Depressive symptomatology rates among indigent mothers of young children are in the range of 40 – 50 percent (Lanzi, Pascoe, Keltner, & Ramey, 1999; Orr, James, Burns, & Thompson, 1989), with a 2- to 3-fold increased risk for depression in their children (Weissman et al., 2006). In about 80% of the cases, treatment can help alleviate symptoms of depression; however, about 2/3 of people do not seek help (Robins & Regier, 1990), and for many their symptoms go unnoticed by health practitioners due to a variety of reasons, including lack of recognition (Gjerdingen & Yawn, 2007). In general, adolescent mothers, ranging in ages from 15 – 18 years, have been shown to be more depressed than first-time adult mothers ages 22–35 years (Whitman, Borkowski, Keogh, & Weed, 2001). The etiology of depression and how early and unplanned onset of parenthood may impact the course of depression and child neglect, however, are not well-documented (Zuckerman, Amaro, & Beardslee, 1987). It is often thought that situational depression is due to lack of knowledge, experience, and resources and that depression may impede individuals from “acting.” The role of depression in adolescent mothers (including the onset, severity, and duration) has yet to be fully explored. It is clear that maternal depression is endemic in low-income families, and that within poverty, there are many stressors that potentially increase depression (Lanzi, Pascoe, Keltner, & Ramey, 1999). The current study explores the variation of adolescents’ moods and parenting behavior through multiple measures of depression and parenting behaviors at multiple time periods. The parenting behaviors and mood fluctuations of adolescent mothers is compared to that of a matched adult sample of mothers. These comparisons are necessary to assess whether potentially neglectful parenting behavior is a function of age, stage, or experience. Becoming an adolescent mother often takes the teen off society’s normative life trajectory. The adolescent is no longer able (or as able) to participate in age-typical social events and sports, nor is she able to date as easily. The early onset of parenthood often inhibits the development of stable relationships and in many cases, the adolescent mother often faces the daunting responsibility of being a parent with minimal or no support from a partner (Brooks-Gunn & Furstenberg, 1986; Lesser, Anderson, & Koniak-Griffin, 1998). Whitman, Borkowski, Keogh, and Weed (2001) found that only 6% of infants born to adolescent parents received support from a father or male figure. The support provided by the adolescent mother’s own mother is key as well (Lesser, Anderson, & Koniak-Griffin, 1998). Even though adolescent mothers assume a great deal of adult responsibility by becoming a mother, they are still children themselves and the grandparents continue to have an obligation to meet their daughters’ needs. Further, it is often the case that adolescent mothers are the children of adolescent mothers themselves, who may not have adequate time, energy, and resources to provide support to their daughters. These combined factors often place the adolescent mother in an environment where there is little support for her needs, which in many cases, may translate into the adolescent mother becoming depressed and not being able to, or wanting to, provide for the needs of her newborn child. In this paper, we explore the underlying factors associated with the prevalence of depression among a sample of first time adolescent and adult mothers. Using a diverse sample of mothers, we aim to document: (1) the rates of positive depression screens and their fluctuations and stability from the prenatal period through 6 months postpartum; (2) the most salient individual and family ecological factors associated with positive maternal depression screens; and (3) how maternal depression affects mother’s parenting and children’s development. This paper is one of several reports that utilize data from the Parenting for the First Time Project (Centers for the Prevention of Child Neglect, year), a landmark 4-site NICHD prospective longitudinal study of early predictors and precursors of parenting among first children born to adolescent and adult mothers. The study includes multiple measures including direct observation, interviews, self-report, and developmental assessments. Conclusions and recommendations for addressing depression among first-time mothers in terms of research and clinical practice are presented.