Changes in survival of twins delivered after twin-twin transfusion syndrome versus preterm singletons over the calendar years 1970-1994.

Overview

OBJECTIVE: The use of serial amniotic fluid volume reduction for the treatment of twin-twin transfusion syndrome (TTTS) became available about 1986 and may account for a recent increase in survival of TTTS twins. To determine whether the increase in survival has been due to advances in neonatal care rather than the advent of amnioreduction, the current study evaluated whether increases in survival of preterm TTTS twins were greater than increases in survival of preterm singletons from studies before 1986 compared to studies after 1986. METHODS: Medline literature search identified all reported cases of TTTS and all reports of severely preterm neonatal survival. Studies were divided into groups according to gestational age at birth (27 weeks) and midyear of each study (1986). Comparison was performed of the increase in survival from pre-1986 studies to post-1986 studies between preterm singletons and TTTS twins. RESULTS: When comparing studies from before 1986 to after 1986, there was no difference in the increase in survival between preterm (>27 weeks) TTTS twins (67-92%) and preterm (>27 weeks) singletons (79-91%) (p = NS). When comparing studies from before 1986 to after 1986, there was a greater increase in survival among severely preterm (