title: Maternal and neonatal risk factors for mental retardation: defining the 'at-risk' child.
abstract: OBJECTIVE
  To determine how mental retardation at age seven is related to certain maternal, perinatal, and neonatal characteristics.
  
  
  METHODS
  A sample of 35,704 children followed from the prenatal period to age 7 years in the Collaborative Perinatal Project provided data on nine maternal and pregnancy characteristics and 12 neonatal factors.
  
  
  RESULTS
  Low socioeconomic status of the family (SES) accounted for 44-50% of mental retardation and a low level of maternal education accounted for 20%. Other prenatal factors with significantly elevated relative risks, (P < 0.05) were maternal IQ score less than 70, weight gain in pregnancy less than 10 pounds and multiple birth. Maternal anemia in pregnancy accounted for 14% of mental retardation in blacks, and, urinary tract infections accounted for 6% of mental retardation in whites. Significant elevations in relative risk were found for major genetic and post-infection syndromes, CNS malformations, cerebral palsy, seizures, abnormal movements or tone, and low birth weight. Relative risk was also significantly increased with low 1 minute APGAR, primary apnea, and head circumference and length more than 2 SD below average but only in the low SES black subgroup.
  
  
  CONCLUSIONS
  Early developmental events can be ranked on the basis of the strength of their association with mental retardation and such rankings can be used as a guide for defining risk status in early infancy.
authors.affiliation: Department of Pediatrics, University of Colorado, School of Medicine, Denver, USA.
authors.forename: B W
authors.initials: BW
authors.lastname: Camp
authors.forename: S H
authors.initials: SH
authors.lastname: Broman
authors.forename: P L
authors.initials: PL
authors.lastname: Nichols
authors.forename: M
authors.initials: M
authors.lastname: Leff
mesh_terms: D001034:Apgar Score; D001049:Apnea / Q000150:complications; D002490:Central Nervous System / Q000002:abnormalities; D002648:Child; D015331:Cohort Studies; D004493:Education; D005006:Ethnicity; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007231:Infant, Newborn; D008607:Intellectual Disability / Q000453:epidemiology* / Q000209:etiology; D008297:Male; D009034:Mother-Child Relations; D011247:Pregnancy; D011248:Pregnancy Complications; D012307:Risk Factors; D012959:Socioeconomic Factors; D014888:Wechsler Scales