Lecithin-sphingomyelin ratio

a ration of 1.9 is considered to indicate fetal lung maturity. 

The cortisol from the fetus and mother play a stimulatory role in the development of the lungs which will show a higher Lecithin to Sphingomyelin ratio.

Unrelated:

but do not for get that the enzyme deficiency in Niemann-Pick is sphingomyelinase so there is a build up of sphingomyelin