关键词: 小于胎龄儿, 病因学, 追赶性生长, 认知发育, 代谢性疾病

Abstract: The incidence of small for gestational age（SGA） is not low in China. The pathogenesis is complex，including placental，maternal and fetal factors. The fetal factors are getting more and more attention，especially genetic etiologies. Managements of SGA include catch-up growth and prevention and treatment of short- and long-term complications of multiple systems. Appropriate catch-up growth is important. The contraindications of growth hormones should be kept in the mind of clinical doctors. Complications of multiple systems include neural development and cognition impairments，cardiovascular and metabolic disorders，pubertal development and fertility issues. Because of similar growth risks，intrauterine and extrauterine growth retardation（IUGR/EUGR） deserves equal attention of clinical doctors.

Key words: small for gestational age, etiology, catch-up growth, cognitive development, metabolic diseases