IRCT201509211788N11 IRCT 2016-01-30 International Campus University of Medical Sciences- Research Center School of Nursing and Midwifer The effects of prone and supine positioning on abdominal distention. Comparison between supine and prone positions on the abdominal distention in premature infants supported with nasal positive airway pressure. 2015-09-23 anticipated 35 Complete https://irct.ir/trial/1371 interventional Randomization: Randomized, Blinding: Not blinded, Placebo: Not used, Assignment: Crossover, Purpose: Supportive. N/A Abdominal Distention. This cross over study was done on 35 infants who are treated with nasal ventilation positive pressure. After selecting the samples, the informed consent will obtained from the parents of the babies. Thus, half of the babies in the study first and then lying prone, supine and the other half of the babies in the supine position and then the abdomen will be a lying position and results of the study will be compared together. Researcher in order to determine abdominal distention in preterm infants with respiratory distress syndrome under continuous positive airway pressure ventilation will record the pressure on the airways and also amount of received milk in a day. After ensuring of receiving the milk by oral or gavage and after 15 minutes the measurement of abdominal circumference will start. Also before giving positions to register waist with meter paper that the 1 cm above the navel will be measured, waist to stabilize the situation and the loss due to positions prior to 60 minutes before any positions, with meter Paper will be measured by the researcher. It measures 30, 60, 90, 120 minutes after the position ultimately taken scores of abdominal distention in these two positions, will be compared with each other..