If the widening of the fetal hyaline septum is less than 1cm, the optimal time for absorption is about 3 to 6 months after delivery. If it is greater than 1cm, it may be caused by pathologic factors such as chromosomal disorders, and usually does not absorb on its own, requiring termination of pregnancy if necessary. The septum lucidum is the septum between the bilateral lateral ventricles. The septum lucidum has two layers, composed of fibrous tissue membranes, which are separated during fetal life and can be closed after birth in most patients, but some patients do not have a complete closure, which may result in widening of the septum lucidum. If the width of the diaphragm is less than 1cm, it is a benign lesion with no obvious clinical significance and does not require special treatment, and can be completely absorbed within 3-6 months after delivery. If the width of the septum is larger, it is pathological, caused by chromosomal abnormality of the fetus, or inappropriate medication taken by the pregnant woman, etc., which usually will not be absorbed by itself, and the development of the fetus is abnormal at this time, so it should be examined thoroughly, and termination of pregnancy is needed if necessary. If the pregnant woman found the widening of the fetal septum pellucidum cavity, it is recommended to go to the hospital in time to seek medical treatment, to clarify the specific causes, and then take appropriate methods of treatment.