Mortality rates in low-birth-weight infants born after a positive contraction stress test.

Perinatal mortality rates and the indications for contraction stress tests (CSTs) were studied in 46 patients with positive test results and who gave birth to infants weighing between 500 and 1 500 g. Severe pre-eclampsia and intra-uterine growth retardation were the indications for the CST in the large majority of patients. The perinatal mortality rate for infants weighing between 500 and 1 000 g was 76.9%, for infants between 1 001 and 1 250 g 38.5%, and only 25% when the infants weighed 1 251 - 1 500 g. After conservative treatment because of fetal immaturity only 1 of 7 infants was born alive, but after immediate delivery by caesarean section there was a high rate of fatal hyaline membrane disease in infants weighing less than 1 000 g. The real danger of intra-uterine death in the presence of a positive CST result indicates prompt delivery when the fetus has a reasonable chance of survival in the neonatal period.