Low-income Adolescent Mothers Research Articles

Maternal self-efficacy and emotional well-being in Chilean adolescent mothers: the relationship with their children's social-emotional development.

BackgroundLow maternal self-efficacy and high levels of anxiety, depression, and stress can be triggered in adolescent mothers due to an incomplete development process that makes them physically or psychologically unprepared for the responsibilities of motherhood and parenting. These factors may be linked to difficulties with their children’s social-emotional development. The present study aims to: (a) analyze the relationship between maternal self-efficacy and stress, depression, and anxiety levels in low-income adolescent mothers; (b) examine the relationship between maternal self-efficacy and well-being with children’s social-emotional development; and (c) describe the effects of maternal self-efficacy on children’s social-emotional development, mediated by maternal well-being.MethodsA sample of 79 dyads comprising low-income Chilean adolescent mothers aged from 15 to 21 years old (M = 19.1, SD = 1.66) and their children aged 10 to 24 months (M = 15.5, SD = 4.2) participated in this research. A set of psychometric scales was used to measure maternal self-efficacy (Parental Evaluation Scale, EEP), the mothers’ anxiety and depression (Hospital Anxiety and Depression Scale, HADS), maternal stress (Parental Stress Scale, PSS), and the children’s social-emotional development (Ages and Stages Questionnaire Socio-emotional, ASQ-SE). Bivariate analyses and mediation models were employed to estimate and test the relevant relationships.ResultsA bivariate analysis showed that maternal self-efficacy was negatively related to the mother’s anxiety, depression, and stress. Moreover, there was a significant relationship between maternal self-efficacy and maternal stress, and children’s self-regulation and social-emotional development. Maternal self-efficacy, mediated by maternal anxiety, depression, and stress scores, had a significant effect on the development of children’s self-regulation.ConclusionsThe results confirm the importance of adolescent mothers’ emotional well-being and maternal self- efficacy with respect to their children’s social-emotional development. This makes it necessary to have detailed information about how emotional and self-perception status influences a mother’s role in the development of her children.

A randomized controlled trial testing the efficacy of a Nurse Home Visiting Program for Pregnant Adolescents

To test the efficacy of a nurse home visiting program (HVP) on child development, maternal and environmental outcomes in the first years of life. We conducted a randomized controlled trial to test the efficacy of Primeiros Laços, a nurse HVP for adolescent mothers living in a poor urban area of São Paulo, Brazil. Eighty adolescent mothers were included and randomized to receive either Primeiros Laços (intervention group, n = 40) or healthcare as usual (control group, n = 40). Primeiros Laços is a home visiting intervention delivered by trained nurses that starts during the first 16 weeks of pregnancy and continues to the child’s age of 24 months. Participants were assessed by blind interviewers at 8–16 weeks of pregnancy (baseline), 30 weeks of pregnancy, and 3, 6, 12, and 24 months of child’s age. We assessed oscillatory power in the mid-range alpha frequency via electroencephalography when the children were aged 6 months. Child development was measured by the Bayley Scales of Infant Development Third Edition (BSID-III). Weight and length were measured by trained professionals and anthropometric indexes were calculated. The home environment and maternal interaction with the child was measured by the Home Observation and Measurement of the Environment. Generalized estimating equation models were used to examine intervention effects on the trajectories of outcomes. Standardized effect sizes (Cohen’s d) were calculated using marginal means from endpoint assessments of all outcomes. The trial was registered at clinicaltrial.gov: NCT02807818. Our analyses showed significant positive effects of the intervention on child expressive language development (coefficient = 0.89, 95% CI [0.18, 1.61], p = 0.014), maternal emotional/verbal responsivity (coefficient = 0.97, 95% CI [0.37, 1.58], p = 0.002), and opportunities for variety in daily stimulation (coefficient = 0.37, 95% CI [0.09, 0.66], p = 0.009). Standardized effect sizes of the intervention were small to moderate. Primeiros Laços is a promising intervention to promote child development and to improve the home environment of low-income adolescent mothers. However, considering the limitations of our study, future studies should be conducted to assess Primeiros Laços potential to benefit this population.Clinical Trial Registration: The study was registered at clinicaltrial.gov (Registration date: 21/06/2016 and Registration number: NCT02807818).

Maternal Parenting Electronic Diary in the Context of a Home Visit Intervention for Adolescent Mothers in an Urban Deprived Area of São Paulo, Brazil: Randomized Controlled Trial.

BackgroundPregnancy during adolescence is prevalent in low- and middle-income countries (LMICs), which is associated with various adverse outcomes that can be prevented with home visiting programs. However, testing these interventions in LMICs can be challenging due to limited resources. The use of electronic data collection via smartphones can be an alternative and ideal low-cost method to measure outcomes in an environment with adverse conditions.ObjectiveOur study had two objectives: to test the efficacy of a nurse home visiting intervention on maternal parenting and well-being measured by an electronic daily diary (eDiary), and to investigate the compliance rate of the eDiary measurement method.MethodsWe conducted a randomized controlled trial to test the efficacy of Primeiros Laços, a nurse home visiting program, for adolescent mothers living in an urban deprived area of São Paulo, Brazil. A total of 169 pregnant adolescents were assessed for eligibility criteria, 80 of whom were included and randomized to the intervention (n=40) and control group (care as usual, n=40). Primeiros Laços is a home visiting intervention delivered by trained nurses tailored to first-time pregnant adolescents and their children, starting during the first 16 weeks of pregnancy until the child reaches 24 months of age. Participants were assessed by blind interviewers at 8-16 weeks of pregnancy (baseline), 30 weeks of pregnancy, and when the child was 3, 6, and 12 months of age. At 18 months, participants were assessed regarding maternal parenting and parental well-being using a 7-consecutive-day eDiary. The smartphone app was programmed to notify participants every day at 9:00 PM over a period of seven days.ResultsWe were able to contact 57/80 (71%) participants (29 from the intervention group and 28 from the control group) when the child was 18 months of age. Forty-eight of the 57 participants (84%) completed at least one day of the eDiary protocol. The daily compliance rate ranged from 49% to 70%. Our analyses showed a significant effect of the intervention on parental well-being (B=0.32, 95% CI [0.06, 0.58], P=.02) and the maternal parenting behavior of the mother telling a story or singing to the child (odds ratio=2.33, 95% CI [1.20, 4.50], P=.01).Our analyses showed a significant effect of the intervention on parental well-being (B=0.32, P=.02) and the maternal parenting behavior of the mother telling a story or singing to the child (odds ratio=2.33, P=.01).ConclusionsThe Primeiros Laços intervention improved maternal parenting and parental well-being, demonstrating its promise for low-income adolescent mothers. The compliance rate of the eDiary assessment showed that it was generally accepted by adolescent mothers with limited resources. Future studies can implement ambulatory assessment in LMICs via smartphones to measure mother and child behaviors.Trial RegistrationClinicalTrials.gov NCT02807818; https://clinicaltrials.gov/ct2/show/NCT02807818

Stigma and utilization of treatment for adolescent perinatal depression in Ibadan Nigeria

BackgroundDepression is a common and severe disorder among low-income adolescent mothers in low-and middle-income countries where resources for treatment are limited. We wished to identify factors influencing health service utilization for adolescent perinatal depression, in Nigeria to inform new strategies of care delivery.MethodsFocus Group Discussions (FGDs) were conducted among purposively selected low-income young mothers (with medical histories of adolescent perinatal depression), and separately with primary care clinicians treating this condition in Ibadan, Nigeria. Participants from this community-based study were from the database of respondents who participated in a previous randomized control trial (RCT) conducted between 2014 and 2016 in 28 primary health care facilities in the 11 Local government areas in Ibadan. Semi-structured interview guides, framed by themes of the Behavioral Model for Vulnerable Populations, was developed to obtain views of participants on the factors that promote or hinder help-seeking and engagement (see additional files 1 & 2). FGDs were conducted, and saturation of themes was achieved after discussions with six groups. Transcripts were analyzed using content analysis.ResultsA total of 42 participants, 17 mothers (who were adolescents at the time of the RCT), and 25 care providers participated in 6 FGDs. The availability of care for perinatal depression at the primary care level was an important enabling factor in healthcare utilization for the adolescents. Perceived health benefits of treatment received for perinatal depression were strong motivation for service use. Significant stigma and negative stereotypes expressed by care providers towards adolescent pregnancy and perinatal depression were obstacles to care. However, individual patient resilience was a major enabling factor, facilitating service engagement. Providers trained in the management of perinatal depression were perceived to deliver more tolerant and supportive care that adolescent mothers valued.ConclusionsParticipants identified unsupportive and stigmatizing clinic environments towards pregnant and parenting adolescents as significant barriers to accessing available care. Interventions to reduce stigma among healthcare providers may improve services for this vulnerable population.

Attachment and social support matters: a longitudinal moderated mediation on the link between maternal depression and maternal behaviours in at-risk adolescent mothers

ABSTRACT Adolescent motherhood tends to occur among vulnerable backgrounds, with increased environmental stressors which might jeopardize the quality of mother-infant interaction. One important factor affecting mother-infant interactions is mothers’ depressive symptoms. However, dispositional (e.g. attachment orientation) as well as external characteristics (e.g. social support) might affect this relation. This study examined longitudinally the effects of postpartum depression on maternal behaviours and explored the role played by social support and attachment orientation on this link in a sample of 35 low-income Brazilian adolescent mothers of infants 12 months old. Self-reported maternal depression and social support scales were answered by mothers and maternal behaviours were videotaped and coded at 6 and 12 months postpartum. Self-reported attachment was obtained at 12 months postpartum. Perceptions of social support mediated the association between mothers’ depression and mothers’ positive behaviours only for those with higher levels of attachment anxiety. Findings could be helpful to intervention programmes targeting adolescent mothers to promote the quality of interaction.

Feasibility of treating depression in pregnant adolescents using brief interpersonal psychotherapy

ABSTRACTThe current study examines a pilot study testing the feasibility of treating antenatal depression in public health clinics serving low-income adolescents using adapted brief interpersonal psychotherapy for depression in pregnant adolescents (IPT-BPA). This research addresses the disproportionate incidence of antenatal depression and its associated negative outcomes, including postpartum depression, among low-income adolescent mothers. Participants (N = 14) were recruited from two county-based public prenatal care clinics. Eligible participants were pregnant adolescents with major depression. Participants received nine sessions of IPT-BPA. Depressive symptoms were measured pre-and post-treatment. Differences were examined using paired t-tests. Most (81%) referred adolescents completed screening, and 73% met eligibility criteria. Of 16 eligible adolescents, 14 (87.5%) consented to participation, and 13 (93%) completed IPT-BPA. Participants who completed IPT-BPA experienced significant decreases in depression. The successful recruitment and retention of pregnant, depressed adolescents combined with significant, positive post-treatment changes in depression support the feasibility of treating adolescent perinatal depression in public health clinics using IPT-BPA.

Effect of Gestational Weight Gain and Prepregnancy Body Mass Index in Adolescent Mothers on Weight and Body Mass Index of Adolescent Offspring

PurposeThe purpose of the study was to examine the association of the gestational weight gain and prepregnancy body mass index (BMI) of low-income adolescent mothers with the risk of their children being overweight and/or obese in late adolescence. MethodsStudy subjects were low-income, primiparous adolescents (n = 360) who self-identified as black and participated in the New Mothers Study in Memphis, Tennessee, and their children. Gestational weight gain was examined as a continuous variable and also categorized into overgain, recommended gain, and undergain following the 2009 Institute of Medicine guidelines. The effects of maternal prepregnancy BMI percentiles and calculated BMI were also considered. Multivariable logistic and linear regression models were used. The main outcome measures were offspring overweight, obesity, and BMI. ResultsThirty-nine percent of offspring were overweight or obese. Higher maternal gestational weight gain increased the risk for offspring overweight and obesity. There was an interaction between gestational weight gain and prepregnancy BMI: offspring of mothers with a BMI percentile ≤76 were at greater risk of obesity with higher maternal weight gain. If mothers with a BMI percentile between the 29th and 83rd percentiles overgained, offspring were at greater risk for overweight. Using calculated BMIs, if a mother's BMI was ≤26 kg/m2, offspring risk for obesity was greater with higher gestational weight gain. ConclusionsHigh gestational weight gain had a larger effect on offspring overweight and obesity if maternal prepregnancy BMI percentile was ≤76. The gestational weight gain of primiparous adolescents who self-identified as black had an effect on offspring weight.

Tools for teen moms to reduce infant obesity: a randomized clinical trial.

BackgroundUnhealthy infant feeding practices, such as a combination of formula feeding and early introduction of solids may lead to rapid or excessive weight gain in early infancy. Adolescent mothers’ feeding behaviors are most directly related to infant weight gain in the first year of life. Compared to adult mothers, adolescent mothers are less knowledgeable, less responsive, more controlling, and less skilled in infant feeding, which interferes with infants’ healthy growth. The Tools for Teen Moms trial aims to compare the effect of a social media intervention for low-income adolescent, first-time mothers of infants 2 months of age or younger, versus standard care on infant weight, maternal responsiveness, and feeding style and practices. The intervention is conducted during the infant’s first four months of life to promote healthy transition to solids during their first year. Tools for Teen Moms is an intervention delivered via a social media platform that actively engages and coaches low-income adolescent mothers in infant-centered feeding to reduce rapid/excessive infant weight gain in the first six months of life.Methods/DesignWe describe our study protocol for a randomized control trial with an anticipated sample of 100 low-income African- American and Caucasian adolescent, first–time mothers of infants. Participants are recruited through Maternal-Infant Health Programs in four counties in Michigan, USA. Participants are randomly assigned to the intervention or the control group. The intervention provides infant feeding information to mothers via a web-based application, and includes daily behavioral challenges, text message reminders, discussion forums, and website information as a comprehensive social media strategy over 6 weeks. Participants continue to receive usual care during the intervention. Main maternal outcomes include: (a) maternal responsiveness, (b) feeding style, and (c) feeding practices. The primary infant outcome is infant weight. Data collection occurs at baseline, and when the baby is 3 and 6 months old.DiscussionExpected outcomes will address the effectiveness of the social media intervention in helping teen mothers develop healthy infant feeding practices that contribute to reducing the risk of early onset childhood obesity.Trial registrationClinical Trials.Gov NCT02244424, June 24, 2014

The Voice of Low-Income Adolescent Mothers on Infant Feeding

Adolescent mothers' feeding practices impact infant weight gain. Infant obesity, especially in low-income families, is rapidly increasing. The aim of the exploratory study reported here was to identify factors affecting low-income African American and non-Hispanic White adolescent mothers' infant feeding practices and useful learning modalities. Two focus groups were conducted by a trained facilitator using a semi-structured topic guide. Three themes emerged: (1) feeding decisions related to introduction of solid foods; (2) feeding information/advice provided by others; and (3) useful learning strategies. These themes can be used by Extension professionals in designing nutrition education programs for adolescent mothers.

Preventing Subsequent Births for Low-Income Adolescent Mothers: An Exploratory Investigation of Mediating Factors in Intensive Case Management

We used a quasi-experimental design to examine the impact of intensive case management (ICM) on preventing 3-year subsequent births for low-income adolescent mothers. We used χ(2) and mediation analyses, respectively, to test whether ICM reduced likelihood of subsequent births and whether birth control and perceived social support mediated this relationship. Participants in ICM were less likely to have a subsequent birth within 3 years, but we found no evidence for mediators. This study suggests that ICM may be effective in preventing subsequent births for adolescents.

Adolescent motherhood and developmental outcomes of children in early Head Start: The influence of maternal parenting behaviors, well-being, and risk factors within the family setting.

This longitudinal study examined the influence of parenting behaviors, well-being, and risk factors of low-income adolescent mothers on the cognitive and language abilities of children from infancy to age 3. Participants consisted of 1,240 mother-child dyads enrolled in the Early Head Start Research and Evaluation Project. Data were collected using structured interviews with the mothers and from videotaped mother-child interactions during play activities when children were approximately 14 months old and again at 36 months of age. Positive parenting behaviors exhibited toward the 14-month-old children predicted gains in both cognitive and language abilities more so than did maternal well-being, risk factors within the family setting, and demographic risk factors. Gains in cognitive abilities from infancy to age 3 were predicted by supportive parenting, higher family resources, and lower family conflict when children were infants. Gains in language abilities were predicted by supportive parenting, support for language and learning in the home environment, and higher family resources when children were infants. Finally, path analyses showed that maternal age had an indirect effect on child cognitive and language abilities at age 3 through effects on parenting behaviors. Older mothers were more likely to be supportive during play at age 14 months, which in turn promoted enhanced developmental outcomes at age 3. Implications for intervention and future research are discussed.

Predictors of representational aggression in preschool children of low-income urban African American adolescent mothers.

Responses to five doll-story stems thematically related to attachment experiences with the mother were videotaped in the home and used to evaluate child, maternal, and environmental predictors of representational aggression in 93 preschool children of African American women receiving public assistance who had become pregnant as teenagers. Significant correlations were found between representational aggression and child's gender (male), birth weight, maternal depressive affect, maternal educational attainment, recent employment, mother's historical residence with her own mother, and felt social support, accounting for 40% of the variance in representational aggression. A significant Felt Social Support × Gender interaction effect suggested that girls of mothers who perceive higher levels of felt social support are more likely to represent less aggression in their stories; felt social support was not associated with boys' representational aggression. A significant Felt Social Support × Employment interaction effect suggested that representational aggression is associated with lower levels of felt social support only among employed mothers. Findings suggest that different pathways exist for representational aggression in children of low-income adolescent mothers, which nevertheless share predictors associated with poverty.

Predictors of depressive symptomatology among low-income adolescent mothers

Predictors of depressive symptomatology among low-income teen mothers (N = 751) were explored. Younger teen mothers were not more depressed than older teen mothers. There was a significant interaction effect for partner status and ethnicity. For African-Americans, partnered teen mothers were more likely than non-partnered teen mothers to be depressed. For Latinas, partnered teen mothers were less likely than non-partnered teen mothers to be depressed. Future research should be conducted to examine how ethnicity interacts with predictors of depression.

Individual Differences in the School Performance of 2nd-Grade Children Born to Low-Income Adolescent Mothers: Findings From an 8-year Longitudinal Study

The purpose of this study was to investigate factors that contribute to individual differences in the school performance of 2nd-grade children born to adolescent mothers. The sample for this study was 90 low-income adolescent mothers and their children. Data were collected from the adolescent mothers and their first-born children, now in 2nd grade, by interviewing the mothers and assessing the children at home and in the classroom. The paraprofessional family advocates who provided services to the families also assessed the parenting practices of the adolescent mothers. The children's school performance in 2nd grade relative to their peers was rated by their teachers at the end of the year in three different areas: social adjustment, academic performance, and academic motivation. Results showed that early home environment and parenting skills predicted children's social adjustment at the end of 2nd grade, and the relation was mediated by receptive vocabulary at 54 months, academic performance at the beginning of school entry, and social adjustment in 1st grade. Similar results were obtained when academic achievement and academic motivation were the outcomes of interest. Children who lived in a more supportive home environment during the preschool years were more competent prior to school entry, which in turn, predicted school performance in 1st and 2nd grade.

Heart Rate Correlates of Attachment Status in Young Mothers and Their Infants

To explore heart rate (HR) correlates of attachment behavior in young mothers and their infants to generate specific hypotheses and to provide pilot data on which studies to test those hypotheses might be based. Using the strange situation procedure, patterns of attachment were assessed in 41 low-income adolescent mothers and their infants. During the procedure, the HRs of the infants and mothers were recorded. The HR changes were analyzed and infant attachment group differences were examined. Infants in all attachment groups demonstrated a similar HR response. There were, however, notably different behavioral reactions in the insecure groups: relatively increased behavioral distress in the insecure/resistant infants and relatively decreased behavioral distress in insecure-avoidant infants. Mothers of insecure-resistant infants demonstrated elevated HRs during reunions and the insecure/resistant dyads demonstrated lower consistency between HR changes in infant and mother than the secure dyads. The results suggest the discrepancy between attachment-related behavioral reactions and HR response in insecurely attached infants. Maternal and dyadic HR changes vary between the attachment groups.

Predictors of academic motivation in first grade among children born to low-income adolescent mothers

The central question addressed in this study was: What factors are associated with individual differences in academic motivation among first-grade students who were born to low-income adolescent mothers? Data from a 7-year longitudinal study were used to address the question. First-grade teachers assessed academic motivation for 89 children at the end of the school year. We tested a model that children’s experiences in the home prior to school entry influence the developmental trajectories of the children; experiences in the home are likely to influence the cognitive abilities children have when they enter school. More competent children are likely to be more successful on school-related tasks, which in turn, should influence level of motivation in the early elementary grades. The results of a path analysis were consistent with this model. Parenting practices and quality of the home environment during the early childhood period were predictive of children’s receptive language skills at age 4.5 years and achievement in the fall semester of first grade; achievement test scores were, in turn, predictive of academic motivation at the end of first grade. We also expected parental support for achievement after school entry to be related to individual differences in academic motivation, but this hypothesis was not supported.

Family Advocates’ Perspectives on the Early Academic Success of Children Born to Low‐Income Adolescent Mothers*

Qualitative analyses were conducted to examine family factors related to individual differences in the early school success of children born to low‐income adolescent mothers from the perspective of paraprofessional family advocates. These families were participants in a 5‐year family support program. Achievement test scores and teacher ratings were used to identify the most successful and least successful students in first grade. Interviews with the advocates about the life experiences of children in each of these groups revealed differences between them in the areas of caregiving practices, maternal characteristics, child characteristics, and contextual sources of stress and support. Given that family service providers are rarely used as informants in this way, the possible strengths and limitations of this approach are discussed.

Perceptions of the School Psychological Environment in Predictingadolescent Mothers’ Educational Expectations

Drawing on theories of educational motivation, this longitudinal study investigates how perceptions of the school psychological environment predict change over time in educational expectations among 81 low-income adolescent mothers. Results suggest that over and above the significant role of baseline educational attainment and expectations, teenage mothers’perceptions of differential treatment at school predict expectations for educational attainment measured 1 year later. Specifically, teens who report that teachers treat them as less smart than they really are and who discourage them from taking certain classes due to their status as mothers show a decline in educational expectations over time.

Perfil nutricional de recém-nascidos de mães adolescentes suplementadas com ferro, em diferentes concentrações, zinco e ácido fólico

O objetivo deste estudo foi avaliar o estado nutricional de recém-nascidos de mães adolescentes com até 18 anos de idade, de baixa renda, suplementadas durante a gravidez com ferro, em diferentes concentrações, zinco e ácido fólico. Estas mães fizeram pré-natal no Instituto de Perinatologia Social do Piauí, Maternidade Dona Evangelina Rosa, no município de Teresina, Piauí, Nordeste do Brasil. As adolescentes foram aleatoriamente distribuídas em cinco grupos: grupos I e II receberam quantidades constantes de ácido fólico (250 µg) e diferentes concentrações de ferro, na forma de sulfato ferroso (120 e 80 mg, respectivamente); grupos III e IV receberam quantidades constantes de ácido fólico (250 µg) associado ao sulfato de zinco (5 mg) e ferro nas concentrações de 120 e 80 mg, respectivamente; e grupo V, considerado controle, recebeu apenas ferro (120 mg) (rotina da Instituição). A avaliação do estado nutricional de 74 recém-nascidos foi feita através de dados referentes à idade, peso, comprimento e perímetro cefálico, por ocasião do nascimento. De acordo com os resultados, as médias de peso (3000 ± 418 g), comprimento (48,07 ± 2,15 cm) e perímetro cefálico (33,53 ± 1,50 cm) encontradas para os filhos de mães do grupo V (rotina local) não diferem dos grupos de intervenção. Conclui-se que os recém-nascidos de adolescentes suplementadas com ferro em diferentes concentrações (120 e 80 mg), zinco e ácido fólico apresentaram um bom perfil nutricional. No entanto, não se observou, entre os grupos de intervenção e o controle, diferenças significativas na duração da gravidez ou no estado nutricional dos bebês.

Caregiving Practices of Low-Income Adolescent Mothers and the Academic Competence of Their First-Grade Children

Objective. This study examines the relation between the caregiving practices of teenage mothers and the academic performances of their children in first grade. Design. The teenage mothers were involved in a family support program, and data were collected on the sample for 7 years (the prenatal period through first grade). The sample included 89 children who participated in the first-grade follow-up and who resided with their biological mothers. Children's school performance was assessed with an achievement test in the fall semester of first grade and with teachers' ratings of academic performance at the end of the spring semester. Caregiving practices were assessed by both the research team and the family advocates who worked with the young mothers during the 5-year family support program; mothers also reported on home support for academic achievement during the first-grade interview. Results. Measures of home environment, advocates' ratings of parenting, and mothers' self-report of support for achievement were positively correlated with children's achievement in first grade. Conclusions. Results from multiple regression analyses were consistent with the view that differences in parenting prior to school entry and in maternal support for achievement once the child enters school are predictive of individual differences in first-grade achievement among children born to low-income adolescent mothers.