Administered in women at increased risk of preterm delivery is associated with a substantial decrease in the risk of respiratory distress syndrome, intraventricular hemorrhage, and neonatal death.
When administered to a pregnant woman before delivery of a very premature infant it accelerates fetal lung maturation and prevents neonatal mortality, respiratory distress syndrome, and brain injury.
Opposite to the above, a large randomized trial involving 98,137 infants in 101 distinct geographical settings demonstrated increased neonatal mortality when antenatal cortical steroids were given to women at risk for preterm birth in low-and middle-income countries(Althabe F).
In large trials and systemic reviews the effectiveness of antenatal corticosteroids among women at risk for late preterm (34-36 weeks) delivery for women undergoing elective full-term 37 week delivery, these more mature infants do not experience mortality benefit but to have lower rates of respiratory distress syndrome and transient tachypnea of the newborn.
Recent guidelines recommend antenatal corticosteroids for women with threatened late preterm birth and for women undergoing full term elective cesarean delivery.
Prenatal exposure to exogenous cortical steroids may be associated with alterations in developmental programming of the fetus, with downstream effects on cardiovascular, metabolic and endocrine functions.
A five year follow up study of antenatal corticosteroids for preterm birth demonstrated that increase corticosteroid exposure was associated with increased risk for neurosensory disability among children subsequently born at term.
Other studies have demonstrated increased risk for psychiatric symptoms among young adults born extremely preterm who been exposed to antenatal corticosteroids.
Among women in low resource countries at risk for early preterm birth, the use of dexamethasone resulting in significantly lower risks of neonatal death alone and stillbirth or neonatal death than the use a placebo, without an increase in the incidence of possible maternal bacterial infection.
In a population study of 670,097 full-term and preterm Finnish children it was found that exposure to antenatal steroids were significantly associated with increased rates of mental and behavioral disorders during childhood (Raikkonen K).
In the above study children who were exposed were a median of 1.4 years younger than an exposed children at the time of diagnosis of mental and behavioral disorders.