The luteal phase is a certain phase of the menstrual cycle, which refers to the period from ovulation to the next menstrual period when the hormone level in the body changes. If you are pregnant, the luteal phase will change from the secretory phase to the proliferative phase, which is conducive to normal fertilization of the egg and ensures healthy fetal growth. If you are not pregnant, the luteal body will develop to atrophy and the next endometrial exfoliation and bleeding for menstruation will occur. If there is a menstrual disorder or irregular menstruation, you should improve the female hormone examination to exclude gynecological inflammation and gynecological tumors and other related diseases, and develop good habits to ensure a regular menstrual period.