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).