Sex hormone levels vary at different stages of the menstrual cycle. The six hormone tests can help determine the cause of amenorrhea, reflect ovarian function, and monitor follicular development and ovulation. The six sex hormones include follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), prolactin (PRL), progesterone (P) and testosterone (T). A woman’s complete menstrual cycle consists of the menstrual, follicular, ovulatory and luteal phases, and the sex hormone values measured during the menstrual phase are the basal values and are most informative. FSH and LH rise slowly at the beginning of the menstrual period, and as the follicle develops and matures, peaks of LH and FSH can occur two days before ovulation. After ovulation the levels of these two hormones fall rapidly. Checking FSH and LH levels provides a preliminary diagnosis of gonadal axis function. Estradiol and progesterone promote endometrial proliferation, but as the corpus luteum shrinks, they decrease, and the endometrium loses the support of these hormones and peels off to bleed, resulting in menstruation. Checking estradiol determines the presence or absence of ovulation and monitors follicular development, and checking progesterone also reflects the function of the corpus luteum. Prolactin fluctuates little during the menstrual cycle and is secreted in large quantities after childbirth. Testosterone, or androgen, is less abundant in women. If women experience menstrual cycle disorders, amenorrhea, abnormal vaginal bleeding, etc., it is recommended that they go to the hospital in time to check the sex hormone six so as to find the cause of the disease and treat the symptoms.