The normal value of parathyroid hormone should be less than 70 pg/ml. The normal value varies from machine to machine measurement, but most will use this reference value. Parathyroid hormone is a hormone secreted by the parathyroid glands and is mainly involved in the metabolism of calcium and phosphorus ions. When the concentration of calcium ions in the body increases, the concentration of phosphorus ions decreases, and the regulation between them depends mainly on parathyroid hormone. If the concentration of parathyroid hormone increases, the concentration of calcium ions will increase, and the excess calcium ions will damage the bone and cause fractures. Uremia increases the concentration of parathyroid hormone during dialysis, and removal of the thyroid gland will affect the secretion of hormones by the parathyroid glands and reduce the concentration of hormones. Kidney failure and hyperthyroidism can also cause a decrease in hormone secretion and disrupt the balance of calcium and phosphorus concentrations in the body.