Abstract Objective In order to establish a foundation for further epidemiological survey of preterm infants throughout China, this paper collected and analyzed medical documents of premature infants from some cities of China. Methods A total of 6 179 preterm infants from 77 hospitals in 16 provinces, municipalities or direct jurisdiction cities in China between January 2002 and December 2003 were enrolled in this study. High risk factors and complications associated with premature birth and incidence and outcome of premature infants were investigated retrospectively.Results The incidence of the preterm infant was 7.8% in neonates born in the department of obstetrics, accounting for 19.7% in hospitalization neonates and with a gender constituent ration of 1.67∶1 (boy∶girl). The preterm infants born at gestational age between 32-36 weeks accounted for 63.5% and those with body weights less than 1 500 g accounted for 32.3% in all premature infants. The most common precipitating factor of premature birth was the abortion history of the mother ( 36.8%), followed by multifetation ( 20.8%),premature rupture of membranes ( 19.8%) and pregnancy-induced hypertension syndrome (12.6%). The most common complication was respiratory system diseases (52.3%), followed by central nervous system disease (33.7%), hyperbilirubinemia (22.6%) and infectious diseases (11.3%),digestive system diseases(10.6%) and circulation system diseases (9.0%). The incidence of complications decreased with the increase of body weight. With the increase of gestational age, a significant decrease in the incidence of complications except hypoxia-ischemic encephalopathy(HIE) was also observed. The desirable outcome of the premature infant rose with the increase of gestational age or body weight.Conclusions The investigation demonstrated the common causes of premature birth and the factors related to the outcome of the premature infant. It provides a basis for decreasing the incidence and improving the prognosis of the premature infant.
