Antenatal Corticosteroids - How Important Is It ?

Injection dexamethasone is recommended by goi for antenatal corticosteroid therapy:

Dexamethasone sodium phosphate & betamethasone acetate + phosphate are the only two efficacious and safe corticosteroids to be used during antenatal period. 

Both these drugs are identical in biologic activity and readily cross the placenta.

Dexamethasone: it is listed in the who essential medicines list, is inexpensive and widely available in facilities for multiple indications.

Betamethasone: in india, the salt betamethasone acetate + phosphate, which requires only two doses at 12 hourly interval, is not available. 
The available salt in india is betamethasone phosphate which is short acting and requires more frequent administration as compared to the former. 
Hence, the dosage schedule of betamethasone phosphate is similar to that of the dexamethasone and has no added advantage over dexamethasone. 

Further, betamethasone is more costly and less stable than dexamethasone at high temperatures. 

However, in individual cases where inj. Dexamethasone is not available the service provider may use inj. Betamethasone phosphate to give the advantage of corticosteroids to the newborns.

Advantage of antenatal corticosteroid therapy:

Timely use of antenatal corticosteroids in a mother reporting with preterm labour before 34 weeks of gestation has the following clinical impacts in newborns who receive good supportive care:

1) 34% reduction in respiratory distress syndrome (rds) 
2) 46% reduction in intra ventricular haemorrhage (ivh) 
3) 54% reduction in necrotising enterocolitis (nec) 
4) 31% reduction in mortality
(goi data) 

Also, it has been reported that use of antenatal corticosteroids leads to other benefits too like reduction in the incidence of pda, reduction in systemic infections, decreased need for respiratory support and therefore, reduced length of hospital stay, low rate of intensive care admissions and finally reduced the cost of care.