Sugar baby is Down syndrome also known as trisomy 21, commonly known as sugar baby, this disease belongs to chromosomal lesions, mainly manifested as mental retardation, with specific changes such as low nasal bridge, wide eye spacing, small eye fissures, often open mouth and extended tongue, passable palm or congenital heart disease, etc. Confirmation of diagnosis requires chromosomal related tests. There is no special effective treatment for this disease, only early start of training and education can improve the intellectual development and physical ability, so as to achieve the goal of self-care, so the high-risk pregnant women should be screened and diagnosed before delivery, so as to achieve early detection and early intervention.