What is considered a normal Lecithin/Sphingomyelin (L/S) Ratio?

The Lecithin/Sphingomyelin (L/S) ratio is an important indicator used primarily to assess fetal lung maturity in the context of prenatal care. A normal L/S ratio of 2:1 or higher suggests that the fetal lungs have developed sufficiently and that the production of surfactant, which prevents the alveoli from collapsing, is adequate.

This ratio is particularly relevant in situations such as preterm labor, where determining lung maturity is critical for managing care effectively. When the ratio is 2:1 or above, it typically indicates that the risk of respiratory distress syndrome (RDS) in the newborn due to immature lungs is significantly reduced.

Lower ratios suggest that lung maturity may not be sufficient, which could lead to complications like RDS. Thus, the correct answer accurately reflects the normative benchmark used in clinical practice for assessing fetal lung maturity.