it’s a pillow. If used in a safe manner pillows are safe.Sitting On any surface can compromise blood flow. This is why paraplegics sometimes get pressure sores and ulcers from sitting too long.People with normals sensation, unlike paraplegics, who have sensation typically don’t allow pressure to the point of dangerous ischemia from sitting because it is uncomfortable.Plastic surgeons would not recommend BBL pillows if they were dangerous.Best, Mats Hagstrom MD