The difference between dexamethasone and betamethasone Preterm delivery

The difference between dexamethasone and betamethasone

Preterm delivery occurs in approximately 10% of all births and results in approximately three fourths of all neonatal deaths.

Complications : respiratory distress syndrome, intraventricular hemorrhage necrotizing enterocolitis corticosteroid therapy has been used to reduce the frequency of neonatal complications, especially respiratory distress syndrome.

dexamethasone and betamethasone enhancing fetal maturation given between 24 and 34 weeks' gestation.

dexamethasone and betamethasone nongenomic effects cell metabolism cell membrane functions. metabolic pathways endothelial nitric oxide synthase

a versus β orientation of the methyl group at position 16.

dexamethasone and betamethasone plasma half-life : 3– 5 h biologic half-life : 36– 72 h cross the placenta in biologically active forms

placental enzyme 11β-hydroxysteroid dehydrogenase: converts cortisol to its inactive metabolic cortisone

in the midgestation human, maternal cortisol level is consistently about 10 times higher than fetal plasma cortisol, suggesting that some maternal to fetal transfer of cortisol occurs.

Animal experiment MICE 1. lung maturity DEX is less potent than BETA in accelerating fetal lung maturity.

Animal experiment MICE: 2. lung weight DEX markedly reduced the lung weight more than BETA. This reduced weight, evident in both sexes, was not reversible and persisted in the young adults

Animal experiment MICE 3. The body weight DEX is less potent than BETA in accelerating fetal lung maturity.

In 1994, the NIH recommended either : 1. betamethasone two 12 -mg doses of given intramuscularly 24 hours apart 2. dexamethasone four 6 -mg doses of given intramuscularly 12 hours apart between 24 and 34 weeks of gestation

according to an NIH consensus : betamethasone is used more often to induce lung maturity Although they both have the same biological activity and adverse effects,

Humen study Baud et al published a retrospective study of 883 infants with gestational ages between 24 and 31 weeks and found that betamethasone was associated with a lower risk of PVL (periventricular leukomalacia) than dexamethasone

Humen study betamethasone maternal perception of fetal movements, fetal brething and body movements observed by ultrasound decreased significantly following the administration of betamethasone. Dexamethasone there was no significant change in fetal movements either as sensed by the mother or as observed by ultrasound

Larger prospective clinical studies and larger sample sizes are needed to obtain more authoritative conclusions.