Effect of corticosteroids and fetomaternal disorders on the L:S ratio

Hydrocortisone or placebo was administered to 126 women at risk for premature delivery who had immature lecithin:sphingomyelin (L:S) ratios in order to induce early surfactant synthesis. In 70 subjects (37 steroid-treated patients, 33 controls), L:S ratio was determined a second time between 9 hours and 7 days after therapy had been initiated. The treatment group showed a significant increase in the L:S ratio when compared to those who received the placebo. Moreover, patients who had fetomaternal disorders that accelerated or delayed lecithin production were also found to have increased L:S ratios after treatment. Fewer newborns developed respiratory distress syndrome (RDS) in the treatment group than in the control group and those in the former category who were affected by RDS had a milder clinical course.