title: ABO and Rh Blood Type Relationship in Parents with more than One Disabled Child.
abstract: BACKGROUND
  Parental blood variables are one of the most important medical-biological causes of intellectual and physical-movement disabilities. The purpose of this study was to identify the relationship between parents' blood variables (ABO and Rh blood type) and their relationship with frequency of intellectual and physical-movement disabilities in Isfahan province.
  
  
  METHODS
  This was a descriptive-analytical study and 494 samples were selected from mothers with more than one disabled child and mothers with normal child using simple and multistage random methods. The data collection was done through questionnaire. Based on Kuder-Richardson Formula 20 (KR-20), the reliability of questionnaire was 0.88. The statistical model in this study was a hierarchical log-linear method.
  
  
  RESULTS
  There was a significant relationship between mother's Rh blood and having disabled child (P=0.002). However no significant relationship between having disabled children and the following variables was found: the father's Rh blood (p=0.2), father and mother's Rh blood together (P=0.5), father blood type (P=0.56), mother blood type (P=0.42), and mother and father blood types together (P=0.7).
  
  
  CONCLUSIONS
  Maternal and fetal blood incompatibility (motherwith negative Rh blood and fetus with positive Rh blood) increased the likelihood of being born with disabilities.
authors.affiliation: Department of Psychology, Behbahan Branch, Islamic Azad University, Behbahan, Iran.
authors.forename: M
authors.initials: M
authors.lastname: Mehrmohammadi
keywords: Blood Type; Intellectual disability; Mental Retardation; Rhesus Blood