Progesterone is produced in the body of both pregnant and non-pregnant women, so the timing of the progesterone test depends on whether the woman is pregnant or not. In women who are not pregnant, the progesterone test should be performed during the third week of menstruation, when the corpus luteum forms and secretes progesterone, which can be tested for progesterone levels. The test for progesterone in women who are sure they are pregnant is usually done by going to the hospital to have a blood test around 40 days after menopause. Progesterone is a very important progesterone for women, which is mainly secreted by the ovaries and has the function of regulating the endocrine maintenance of a stable internal environment. Low progesterone during the non-pregnant period may cause a series of phenomena such as severely reduced menstrual flow, dripping menstruation and irregular menstrual cycle. The progesterone test is also very simple, requiring only about 3 ml of venous blood and the results will be available in one working day. In the case of low progesterone in the early stages of pregnancy, it is associated with embryonic arrest and preterm miscarriage. Therefore, if you have vaginal bleeding and abdominal pain after menopause, you should go to the hospital to check ultrasound to exclude ectopic pregnancy and spontaneous abortion, embryonic abortion, etc. You can also take blood for progesterone test in the hospital at the same time, and if you have low progesterone, you need to take medication to keep the fetus under the guidance of clinician in time to prevent complete miscarriage. The progesterone test is more important for women, especially those with irregular menstruation, acne, obesity, suspected premature ovarian failure and other diseases should be checked.