Hello, and I hope I can help you today. Pain in your buttocks is likely caused by compression of nerves in your pelvis by the growing baby. The position of the head or a sharp body part (like a knee) can hit your sciatic nerve, which exits your pelvis in an area near your lower buttcoks. Lying down and elevating your legs can help relieve this, or wearing an abdominal support (like a girdle or pregnancy belly band - sold in Western maternity stores) can support the baby and take pressure off your pelvis. I hope I was able to answer your question and that my advice was helpful. Best wishes for the rest of the pregnancy, Dr. Brown