The success rate of 30-week bed rest for fetal preservation is not clear. The success rate of fetal preservation is related to the condition, and bed rest is only the most basic method of fetal preservation, which cannot fundamentally improve the success rate. The methods of fetal preservation include bed rest, keeping the urine and feces unobstructed, and applying drugs to preserve the fetus. The success rate of labor preservation varies with different degrees of preterm labor. If the cervical canal is already very short and the uterine opening is open, then preterm labor is likely to occur even with strict bed rest. If there is only tightness and hardness in the lower abdomen, which can be improved after bed rest, then the success rate is high. If there is any adverse reaction such as lower abdominal pain or vaginal bleeding in the 30th week of pregnancy, it is necessary to consult a doctor in time and take the corresponding method of treatment through the doctor’s assessment.