[Changes in the lecithin-sphingomyelin relationship in the amniotic fluid following the effect of dexamethasone].

Amniotic fluid samples were taken by transabdominal amniocentesis from 22 pregnant women in the 32-37th gestation weeks. Determination of lecithin/sphingomyelin ratio showed that in 20 cases the L/S ratio was 2 or less than 2. The patients were treated with i.m. Dexamethason in a total dose of 0,3 mg/kg body weight. Subsequently the L/S determination was repeated. Dexamethason treatment resulted in a significant increase of L/S ratio. In 3 cases out of 22 the L/S ratio was below 2. No neonate developed RDS from this patient material. The authors are convinced that the risk of RDS is an indication for amniocentesis. If the L/S ratio equals 2 or is lower than this value, steroid prophylaxis is recommended.