babies have an increased risk of death or of suffering from serious
complications after birth.
help with the baby's development and therefore increase the chance of
corticosteroids to mothers at risk of preterm delivery, from as early as
23 weeks of pregnancy, lowers rate of death and serious illness for their
Mothers who are at the risk of preterm delivery, benefit
from corticosteroid drugs from as early as 23 weeks of pregnancy. It lowers the
associated risk of death and serious illness for their babies.
seem to benefit most very premature babies, those born as early as 23 weeks..
Administration of corticosteroids helps with the baby's development and
therefore increases the chance of survival after birth, by reducing serious complications.
‘Infants exposed to antenatal corticosteroids at the lowest gestational age had lower rate of death before discharge and better chance of survival.’
carry a greater risk of death and
serious complications after birth such as breathing problems, bleeding into the
brain or infection, compared with babies born at term. The earlier the baby is
born, the greater the risk of death or associated illness.
Current guidelines recommend administering corticosteroids from
23 to 34 weeks of pregnancy (gestation), to women who are at
risk. But the
benefits of corticosteroids for reducing morbidity during the 23rd week had not
been extensively studied.
For the study, a team of US researchers analyzed data of 117,941
infants born between 23 and 34 weeks of gestation from 2009 to 2013,
at 300 neonatal intensive care units across the United States.
After adjusting for variables like birth weight, sex, mode
of delivery and multiple births, death or major illness was analyzed by
gestational age and exposure to antenatal corticosteroids.
The results showed that those infants exposed to antenatal
corticosteroids had significantly lower rate of death before discharge from
hospital at each gestation, compared with infants without
The infants exposed to antenatal corticosteroids at the
lowest gestational age also had higher rate of survival without major illness
while in hospital.
The results also showed that the number of infants needed
to be treated with antenatal corticosteroids to prevent death before discharge
increased from 6 at 23 and 24 weeks of gestation to 798 at 34 weeks of
gestation. This shows that infants born at the lowest gestational ages, as
early as 23 weeks of gestation, benefit most from corticosteroids.
"Among infants born from 23 to 34 weeks' gestation,
antenatal exposure to corticosteroids compared with no exposure was associated
with lower mortality and morbidity at most gestations," say the authors.
"This study highlights for the first time that infants
at the lowest gestations seem to benefit the most from exposure to antenatal
corticosteroids," the authors add.
Being an observational study, no firm conclusions can be
drawn on the causal relationship.
This study "supports the administration of antenatal
corticosteroids in women with threatened preterm labor from 23 to 34 weeks'
In an accompanying editorial, Professor Sarah McDonald at
McMaster University in Canada adds that the administration of antenatal corticosteroids
to women at risk of early preterm birth has been one of the most effective
interventions to improve premature infants' outcomes.
The timing of administration of corticosteroids is critical
to maximizing benefits for very premature babies. It should ideally be
administered within approximately one week of birth, which remains a major
challenge for clinicians.
The findings are published in The BMJ
- Waldemar A Carlo, et al. Exposure to any antenatal
corticosteroids and outcomes in preterm infants by gestational age: prospective
cohort study. The BMJ; (2017) doi.org/10.1136/bmj.j1039