Fetal hemifollicular holoprosencephaly is a type of developmental malformation of the brain that is often associated with chromosomal malformations and anomalies such as trisomy 13-trisomy and trisomy 18-trisomy. It is often a lethal malformation, so it is advisable to terminate the pregnancy promptly if the condition is diagnosed. Fetal hemi-lobular holoprosencephaly usually occurs in the early stages of pregnancy when there is an obstacle in the process of cerebral differentiation, leaving most of the forebrain unseparated, and severe craniofacial anomalies, for which there is no good treatment at present. It is recommended that before getting pregnant again, it is best to go to the hospital for a comprehensive pre-pregnancy examination, and if necessary, chromosome examination can be done for both men and women. Start taking folic acid tablets from the first three months of pregnancy, try to avoid viral infections and ionizing radiation, and quit smoking and drinking.