Prematurity is associated with numerous complications, including neonatal respiratory distress syndrome (RDS), a cause of infant morbidity and mortality.
Tests generally appear in the order most useful for common clinical situations
| Test name: Fluorescence Polarization (Fetal Lung Maturity) |
| ARUP #: 0020486 |
| Methodology: Quantitative Fluorescence Polarization |
| Use: Assess fetal lung maturity (FLM) to time delivery of fetus for optimal outcome Test of choice for urgent clinical situations |
| Limitations: Blood contamination can change results, but immature result will not be classified erroneously as mature Evaluate reports of FLM with caution since no gold standard exists |
| Follow-up: For immature or transitional results, consider another FLM test (cascade testing) |
| Test name: Lamellar Body Counts |
| ARUP #: 0080940 |
| Methodology: Quantitative Automated Cell Count |
| Use: Assess FLM to time delivery of fetus for optimal outcome |
| Limitations: Do not apply reference values for test to other instruments without performing comparison studies Evaluate reports of FLM with caution since no gold standard exists |
| Follow-up: For immature or transitional results, consider another FLM test (cascade testing) |
| Test name: Phosphatidylglycerol |
| ARUP #: 0080275 |
| Methodology: Qualitative Immune Agglutination |
| Use: Assess FLM to time delivery of fetus for optimal outcome |
| Limitations: If gestational age of fetus is <35 weeks, results are likely to be negative 10% of healthy term infants have no measurable PG Not affected by presence of blood or meconium in amniotic fluid Evaluate reports of FLM with caution since no gold standard exists |
| Follow-up: For immature or transitional results, consider another FLM test (cascade testing) |
| Test name: Lecithin-Sphingomyelin Ratio |
| ARUP #: 0080200 |
| Methodology: Quantitative Chromatography |
| Use: Assess FLM to time delivery of fetus for optimal outcome Least-utilized FLM test due to labor intensiveness |
| Limitations: Blood contamination introduces plasma lipids, which increases low values and decreases high values Requires a minimum of 4 hours for results L/S ratio takes more time to perform and is less precise than fluorescence polarization |
| Follow-up: For immature or transitional results, consider another FLM test (cascade testing) |
| Test name: Fetal Fibronectin |
| ARUP #: 0082024 |
| Methodology: Semi-Quantitative Solid Phase/Immunosorbent |
| Comments: Assess risk of preterm delivery |