There are many reasons for low progesterone, mainly due to endocrine dysfunction and disease factors. Due to the poor development of the ovary itself, the receptor for luteinizing hormone on the granulosa cells in the follicular phase is defective, which can lead to poor luteinization of the granulosa cells after the granulosa follicle is ovulated, and the secretion of progesterone is reduced. Endocrine dysfunction can lead to insufficient progesterone secretion by the corpus luteum, which leads to abnormal follicular development, reduced estrogen secretion, insufficient positive feedback to the hypothalamic pituitary gland, and poor luteinizing hormone peak, or a defective low impulse of luteinizing hormone after the peak of ovulation, which leads to poor lutealization after ovulation, resulting in the development of low progesterone.