AUTHOR=Scher Mark S. TITLE=“The First Thousand Days” Define a Fetal/Neonatal Neurology Program JOURNAL=Frontiers in Pediatrics VOLUME=Volume 9 - 2021 YEAR=2021 URL=https://www.frontiersin.org/journals/pediatrics/articles/10.3389/fped.2021.683138 DOI=10.3389/fped.2021.683138 ISSN=2296-2360 ABSTRACT=Gene-environment interactions begin at conception to influence maternal/placental/fetal triads, neonates and children with short and long-term effects on brain development. Life-long developmental neuroplasticity more likely results during critical/sensitive periods of brain maturation over these first 1000 days. A fetal/neonatal program (FNNP) applying this perspective better identifies trimester-specific mechanisms affecting the maternal/placental/fetal (MPF) triad, expressed as brain malformations and destructive lesions. Maladaptive MPF triad interactions impair progenitor neuronal/glial populations within transient embryonic/fetal brain structures by processes such as maternal immune activation. Destructive fetal brain lesions later in pregnancy result from ischemic placental syndromes associated with the great obstetrical syndromes. Trimester-specific MPF triad diseases may negatively impact labor and delivery outcomes. Neonatal neurocritical care addresses the symptomatic minority who express the great neonatal neurological syndromes: encephalopathy, seizures, stroke and encephalopathy of prematurity. The asymptomatic majority present with neurologic disorders before two years of age without prior detection. The developmental principle of ontogenetic adaptation helps guide the diagnostic process during the first 1000-days to identify more phenotypes using systems-biology analyses. This strategy will foster innovative interdisciplinary diagnostic/therapeutic pathways, educational curricula and research agenda among multiple FNNP. Effective early-life diagnostic/therapeutic programs will help reduce neurologic disease burden across the lifespan and successive generations.