The hazards of sleeping with crossed legs mainly include affecting the normal position of the pelvis, compressing the ankle joint, and inhibiting blood circulation in the lower limbs. 1. Affecting the normal position of the pelvis. Sleeping with crossed legs for a long time may cause changes in the normal anatomical position of the pelvis, lateral tilt and so on, which in the long run will easily cause a decline in the stability of the hip joint and pain during activities. 2. Pressure on the ankle joint. Cross-legged will compress the knee and ankle joints, causing pain and even deformation, which will affect the normal function of the joints. 3. Inhibit blood circulation in the lower limbs. Two legs folded posture is bound to compress the lower limbs related blood vessels, will affect the normal blood circulation in the lower limbs. It is not recommended to keep the cross-legged posture while sleeping, if so, you need to change in time to avoid irreparable damage.