It is not possible to determine the exact number of months when a woman with an incomplete mediastinum is most at risk, because the severity of the incomplete mediastinum, the personal constitution of the pregnant woman and the stability of the fetus in the mother’s body vary, and thus the time of risk varies. The risk of miscarriage in the first trimester, preterm labor in the second trimester and miscarriage in the middle trimester is also a risk. If diagnosed with incomplete mediastinum, a woman needs to be cautious throughout her pregnancy and should have regular maternity checks. Pregnant women with incomplete mediastinum pregnancies are advised to take more rest, avoid strenuous activities, and prohibit intercourse during pregnancy to prevent miscarriage. If the patient has an incomplete longitudinal uterus, early hysteroscopic resection of the longitudinal septum is recommended, with regular postoperative medical review, and it is safer to consider pregnancy 3 months after surgery.