Babies with chromosome 13 abnormality will have mental retardation, developmental delay, special facial features, hand and foot deformities, and are prone to give birth to malformed and mentally retarded babies when they grow up. 1. Mental retardation: the baby’s brain cannot develop normally or develops incompletely, and the intelligence is at a relatively low stage. 2. Developmental delay: the baby’s developmental process slows down or the order is not normal, including mental developmental delay, language developmental delay and so on. 3. Special facial features: the appearance of different proportions of head growth, cleft lip, facial flattening and other characteristics. 4. Hand and foot deformities: abnormal development and growth of hands and feet, left-right asymmetry, syndactyly, and so on. 5. Malformations: Fetuses with abnormal development, physical appearance and other abnormalities. Chromosome 13 can have deletion and translocation abnormalities, and the symptoms are different depending on individual differences. It is recommended to carry out detailed treatment under the guidance of doctors.