ABSTRACT
The objective of this study is to investigate the current understanding of neonatal
survival and the willingness to provide aggressive obstetric intervention at the limit
of fetal viability among practicing perinatologists in the United States. A pretested
survey was mailed to members of the Society for Maternal Fetal Medicine. The survey
identified the practitioner's opinion of the lowest limit of viability and gestational
ages at which antenatal steroids and cesarean section would first be provided. We
also attempted to identify practitioner knowledge of survival at 23 and 24 weeks'
gestation and years of perinatal practice. Of the 1244 surveys mailed to members of
the Society for Maternal-Fetal Medicine practicing in the United States, 462 practitioners
replied for a 37% response rate. Fifty percent considered the lower limit of viability
to be 24 weeks' and 44.3% believed the lower limit of viability to be 23 weeks' gestation.
Among respondents, the majority estimated a 0 to 10% survival rate at 23 weeks' and
25 to 50% survival rate at 24 weeks. Only 13% of respondents correctly estimates survival
at 23 weeks' gestation as >25%, and only 17% correctly estimated survival at 24 weeks'
at >50%. Among practitioners, 43.6% would first give antenatal steroids after 24 weeks'
gestation but 55.6%would administer steroids before the beginning of week 24. Twenty-eight
percent would routinely monitor a fetus less than 24 weeks' gestation. Consistent
with this observation, 21% would perform a cesarean section before 24 weeks' gestation.
We find that respondents underestimate the consensus in the most recent literature
on survival of infants born at 23 to 24 weeks. This underestimation may lead to a
limitation in interventions offered.
KEYWORD
Extreme prematurity - fetal viability - obstetric practice - neonatal survival
