Highly Premature Babies Benefit Most from Corticosteroids Before Birth

Very premature babies, those born at 23 weeks of gestation, seem to benefit the most from antenatal corticosteroids.

Highlights:

Premature babies have an increased risk of death or of suffering from serious complications after birth.
Corticosteroids help with the baby's development and therefore increase the chance of survival
Administering 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 babies.

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.

Corticosteroids 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.

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‘Infants exposed to antenatal corticosteroids at the lowest gestational age had lower rate of death before discharge and better chance of survival.’

Premature babies 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.

Analysis

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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.

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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 exposure.

The infants exposed to antenatal corticosteroids at the lowest gestational age also had higher rate of survival without major illness while in hospital.

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Predictions whether 70% of female study participants with threatened preterm labor (TPIL) would or would not give birth prematurely has been done with a blood based diagnostic test.

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.

Conclusion

"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' gestation."

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.

Reference:

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

Source-Medindia