abo and rh blood type relationship in parents with more than one

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. materials and method 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. data were analyzed using spss version 16.   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). conclusion maternal and fetal blood incompatibility (motherwith negative rh blood and fetus with positive rh blood) increased the likelihood of being born with disabilities.