Aim:The etiology of myelomeningocele is multifactorial. Genetic alterations in folate-dependent single carbon metabolism may to cause neural tube defects. ABO and Rhesus (Rh) blood groups, that share similar genetic localisations as folate mechanism, have relations with various metabolic and malignant diseases. The aim of this study was to investigate the relationship between the distribution of ABO or Rh blood group antigens and the incidence of myelomeningocele.Material and Methods:A retrospective data was reviewed of all myelomeningocele patients operated at our hospital between years 2014 and 2019. Age, sex, delivery method, physical and neurological examination findings, and radiological findings alongside with blood type of each patient were recorded. The data of blood group distribution among the study patients was compared to the data of healthy individuals in the same region.Results:Patients with group B and AB showed a higher chance of developing myelomeningocele. Rh-positive blood group was associated with high incidence of myelomeningocele (93.5%), whereas Rh-negative blood group showed least association (6.5%). Rh-positive blood group was also more frequent in patients with myelomeningocele with hydrocephalus and Chiari malformation.Conclusion:ABO and Rh blood groups have an effect on the development of myelomeningocele under the influence of environmental or genetic factors.