OBSTETRICAL JUDGMENTS OF VIABILITY AND PERINATAL SURVIVAL OF EXTREMELY LOW-BIRTH-WEIGHT INFANTS

Objectives. The purpose of the study was to determine whether the obst etrical judgment of viability makes a difference to fetal and neonatal survival of extremely low birthweight infants (500-749 g). Methods. W e assessed the effect of the antenatal judgment of viability in a grou p of 66 infants born weighing from 500 to 749 g. These infants were al ive at maternal hospital admission and were subsequently live-born or stillborn between January 1, 1984, and December 31, 1985. We related t he antepartum assessment of viability and other factors recorded in th e medical record to fetal survival and to postneonatal survival to hos pital discharge. Results. The obstetrical judgment of viability was st rongly associated with outcome. After birthweight and gestational age were controlled, fetuses considered viable were 18 times more likely t o survive (95% confidence interval = 2, 175) than those considered non viable. Conclusions. The effects of obstetrical practices on perinatal mortality must be taken into consideration in estimating the survival potential of very small fetuses and in evaluating the relationship be tween survival and disability.