eng Oriental Scientific Publishing Company Biomedical and Pharmacology Journal 0974-6242 2023-06-30 16 2 1101 1111 10.13005/bpj/2690 49782 article Drobchak M 1 Kitsera N 1 Osadchuk Z 1 Kech N 1 Bondarenko M 2 Kozovyi R 2 Institute of Hereditary Pathology, National Academy of Medical Sciences of Ukraine, Lviv, Ukraine Ivano-Frankivsk National Medical University, Ivano-Frankivsk, Ukraine Prader-Willi syndrome (PWS) is a genetic disease characterized by mental retardation, as well as autism spectrum disorders, obesity and mood disorders. The aim of our study was to research a spectrum of genetic heterogenity and different clinical neurodevelopmental manifestations. Materials and methods: clinical, molecular, genetic and psychological methods were used. We observed 9 children (5 boys and 4 girls) with Prader-Willi syndrome from Lviv and Ivano-Frankivsk regions (Western Ukraine) who were diagnosed and followed-up at the Institute of Hereditary Pathology, National Academy of Medical Sciences of Ukraine, Lviv, for 4 years (2019–2022) and underwent molecular genetic testing. The ages of children ranged from 1 month to 7 years, with the mean value amounting to 3.6 years of age. Results: Our study revealed that 6 (66.7%) out of 9 children with PWS had birth defects. At ultrasound during pregnancy, we observed certain clinical features of the fetus, including fetal intrauterine development delay –5 (55.5%), and higher nuchal translucency measurement – 3 (33.3%). According to the checklist of autism spectrum disorders (CASD), 3 of the examined children with autism syndrome were at risk and required further monitoring, while 5 children scored 18-20 points, which indicated the presence of autistic spectrum and required in-depth monitoring during diagnosis. Stereotypical and repetitive play as a manifestation of problems with social interaction was observed in 3 boys with PWS. In our study, parents had no complaints about aggressive behavior in children with this syndrome. Conclusions: In cases if the children have signs of autism or developmental delay, they should undergo genetic counseling. https://biomedpharmajournal.org/vol16no2/neurodevelopmental-manifestations-and-birth-defects-in-prader-willi-syndrome-findings-from-a-study-in-western-ukraine/ Birth Defects Clinical Manifestations Prader-Willi Syndrome Neurodevelopmental Disorders