It is generally recommended to have the sex hormone test on the 2nd-3rd day of menstruation, mainly because on the 2nd-3rd day of menstruation, women’s hormone levels will drop. The sex hormones examined at this time are basic endocrine, which can reflect the ovarian function of the patient more objectively and can also determine whether the patient has endocrine disorders more accurately. If the patient has other needs, such as to determine the estrogen level before ovulation or to determine the luteal function, the time of the hormone test can be changed according to the patient’s specific situation. If you are checking the patient’s pre-ovulatory estrogen levels, you need to test before the patient ovulates. If you are checking the patient’s luteal function, you will need to have a blood test one week before the patient’s menstrual period.