The morbidity and survival of very-low-birth-weight infants in Taiwan.

Abstract

Advances in obstetrical and neonatal care have increased the survival of very-low-birth-weight (VLBW) infants, defined as infants weighing < or = 1,500 g at birth, in many populations. To understand the morbidity and survival of VLBW infants in Taiwan, the records of all VLBW admitted to the 12 hospitals with a level II+ or level III neonatal intensive care unit (NICU), at < 7 days of age, from January 1 to December 31, 1996, were collected prospectively. A total of 613 VLBW infants (292 males and 301 females) met the enrollment criteria: 305 cases from the northern region, 181 cases from the central region, and 127 cases from the southern region of Taiwan. The mean birth weight was 1,133 g (range, 368-1,500); the mean gestational age (GA) was 28.9 weeks (range, 21-38). Among the VLBW infants, 25.8% were small-for-gestational-age, 90.2% were born to mothers with high-risk factor(s) for preterm delivery, 55% were born by cesarean section, and 68.1% required resuscitation at birth. The percentage of prenatal use of steroids was 52.9%, and < 20% received more than one dose of antenatal steroids. Thirty-three percent were born after antenatal maternal transfer, and the neonatal transfer rate was 23%. The most common neonatal complication was apnea of prematurity (66.1%), followed by respiratory distress syndrome (RDS) (60%). Chronic lung disease occurred in 76 cases (16.5%). The overall survival rate of the 613 VLBW infants was 76.2%; for infants weighing < or = 1000 g at birth, it was 49.2%, and for infants weighing 1,001-1,500 g at birth, it was 88.5%. The survival rate for infants with a GA < or = 26 weeks was 35.3%, and for infants with a GA of 27-36 weeks was 87.5%. No infant with a birth weight < or = 600 g or a GA < 23 weeks survived. The most common cause of death was sepsis, followed by extreme prematurity (GA < or = 23 wks) and RDS. Several perinatal and neonatal factors were related to the mortality. Multiple regression analysis of survival showed that GA < or = 26 weeks, birth weight < or = 800 g, delivery room resuscitation and the occurrence of pneumothorax were related to mortality. Therefore, although the survival rate of VLBW infants admitted to level II(+)-III NICUs showed an improvement over the rate for the previous 20 years in Taiwan, perinatal and neonatal care of extremely preterm infants and neonatal resuscitation programs need to be emphasized to improve the outcome of VLBW infants furthermore.