Oxytocin Treatment in Neonates and Infants With Prader-Willi Syndrome

Inclusion Criteria: 1. Male or female neonate or infant, with PWS genetically confirmed. 2. Age \<92 days (plus a tolerance of up to 8 days maximum) (for preterm infants, born before 37 weeks amenorrhea, corrected age will be applied). 3. Signed informed consent obtained from the parents/holders of parental authority. 4. Parents willing and able to comply with all study procedures. Exclusion Criteria: * 1\. Neonate or infant currently admitted to the emergency care unit for ongoing life-threatening comorbidities like severe respiratory, cardiovascular or neurological abnormalities. 2\. Neonate or infant with prolongation of the QT interval. 3. Neonate or infant without medical insurance. 4. Neonate or infant with hypersensitivity to oxytocin or excipients of the product. 5\. Neonate or infant with concomitant treatment prolonging QT interval 6. Neonate or infant with family history of genetic pathology causing QT interval prolongation. 7\. Neonate or infant with hypokalemia (clinically relevant at the discretion of the doctor). 8\. Neonate or infant participating simultaneously in another interventional study. 9\. Neonates or infants whose parents' situations may jeopardize the interpretation of the results. 10\. Neonates or infants whose parents' refuse video recording, required to respond to the primary objective of the study.