The success of preserving a pregnancy with too low progesterone on day 50+ depends on the quality of the embryo itself and the health of the mother. Most of the miscarriages or abortions seen clinically are due to problems with the quality of the embryos themselves, which are eliminated naturally. However, because of the limitation of examination conditions and level, there is no way to examine the embryo quality in all pregnant women with preterm miscarriage, and most of them are treated with experimental progesterone for fetal preservation. After the treatment with progesterone, if the symptoms of preterm miscarriage disappear and the embryo develops normally on ultrasound, the pregnancy can usually be successfully preserved. However, if no fetal bud or heartbeat is seen on ultrasound after treatment, it is unlikely to be successful. In addition, low progesterone on day 50 of pregnancy can be due to luteal insufficiency, severe thyroid dysfunction, insulin resistance, etc. Therefore, patients need to view the specific cause, treat it, and decide whether fertility preservation treatment is necessary in combination with the results of HCG level and ultrasound examination. Pregnant women with low progesterone are advised to use progesterone instead of treatment according to the doctor’s recommendation, and they can also supplement with diet together by drinking more soy milk and eating more soy products. Also need to pay attention to check after one to two weeks of conditioning treatment to avoid damage to the pregnant woman caused by heavy bleeding. And pregnant women should pay attention to control their emotions and actively cooperate with the treatment.