Antenatal corticosteroids 2022 rcog
Reduces death by 31%
RDS by 44%
IVH 46%
The risk of respiratory morbidity at term is low (~5%) and decreases with advancing gestational age.
Ideally, planned caesarean births should be undertaken at or after 39+0 weeks’ gestation.
Maternal blood glucose levels rise shortly after administration of corticosteroids and can remain elevated for up to 5 days
Betamethasone
Betamethasone is available in two formulations.
Betamethasone sodium phosphate is soluble with a short half-life, while betamethasone sodium acetate is insoluble and has a long half-life.
Dexamethasone
Dexamethasone phosphate is a soluble preparation, which is slightly cheaper than betamethasone sodium phosphate/acetate mix and does not require refrigeration.
Dexamethasone resulted in a lower risk of interventricular haemorrhage (four trials, 549 babies)
betamethasone resulted in less maternal chorioamnionitis than dexamethasone
More recently, a randomised control trial (1346 women, 1509 babies, 79 with follow up to two years) found no differences in the incidence of death or neurosensory disability at two years between dexamethasone and betamethasone phosphate/acetate mix
What are the risks to the baby?
Antenatal corticosteroid administration affects fetal growth. Babies who receive antenatal corticosteroids have a lower birth weight than those that received placebo
most affected with reductions in weight, head circumference and length.
Neonatal hypoglycaemia has also been demonstrated in women with diabetes who have received steroids prior to caesarean birth at term.
The long-term metabolic and neurological consequences of neonatal hypoglycaemia are uncertain.
Regarding requirement of repeated dose
The World Health Organization systematic review and guidance recommends a single rescue course of antenatal corticosteroids if women remain at high risk of preterm birth and more than seven days has elapsed since previous treatment.
A randomized controlled trial demonstrated a 50% reduction in respiratory morbidity by administrating prophylactic betamethasone to women having elective caesarean deliveries beyond 37+0.
About the Author
