The slow rise in body temperature after ovulation is considered to be caused by poor luteal function. Under normal circumstances, after ovulation the corpus luteum begins to form, it will stimulate the nerve center resulting in a rise in body temperature, which is generally 0.3-0.5°C higher than the basal body temperature. If the luteal function is not good, it will lead to bad luteal production, which will cause a slow rise in body temperature, and endocrine disorders will also lead to this situation, you need to go to the hospital to draw blood to check the six hormones. It is also possible that there is no ovulation. You can use ovulation test paper or ultrasound to see if there is normal ovulation. If the luteal function is not good, you need to use progesterone treatment under the guidance of your doctor, which can improve the luteal function. If there is no ovulation, you need to use ovulation-promoting drugs, such as clomiphene, under the guidance of your doctor. Each person’s constitution is different, and changes in body temperature will occur differently, so you need to go to the hospital for regular checkups.