Low progesterone levels caused by luteal insufficiency in the fifth week of pregnancy need to be treated with medication, and be rechecked on a regular basis. Early pregnancy with the increase of gestational weeks progesterone measurement will rise steadily, the normal level of progesterone is conducive to embryo implantation and maintenance of pregnancy. When the corpus luteum is not functioning properly, the progesterone value will become low and increase the risk of early miscarriage, so we should follow the doctor’s instructions to give progesterone intramuscular injection or oral dextroprogesterone and other medications to supplement progesterone to protect the fetus treatment. Low progesterone in early pregnancy can also be accompanied by vaginal bleeding and other symptoms, active treatment 7-10 days after the ultrasound and progesterone value, when the ultrasound suggests that the embryo is well developed and progesterone value is normal can continue the pregnancy, but when the symptoms worsened, progesterone value does not rise, ultrasound suggests that the embryo is not well developed, indicating that miscarriage is inevitable, need to terminate the pregnancy. When the progesterone value becomes low in the fifth week of pregnancy, it needs to be actively treated under the guidance of the doctor.