The normal value of prolactin is 1.61-18.77 ng/ml, which varies slightly depending on the laboratory method and reagents used in each hospital. When looking at the laboratory test, there is usually a normal range marked on the back, which is normal as long as the value is between the lowest and highest values. It is normal to have a high prolactin value after delivery to prepare for the baby’s milk, but if there is no pregnancy and delivery, the high value may cause the menstruation to not come normally, which may be a sign of prolactinoma and can be corrected by bromocriptine.