Which test is sometimes evaluated for fetal lung maturity but is not identified as the most valid marker in contaminated amniotic fluid?

• A. Lamellar body count (LBC)
• B. Phosphatidylglycerol (PG)
• C. Surfactant/albumin ratio
• D. Lecithin/sphingomyelin ratio

Answer: (A)

In fetal lung maturity testing, you look for markers in amniotic fluid that reflect surfactant production. Some markers hold up better when the sample is contaminated. Lamellar body count is a potential indicator, but it isn’t as reliable in contaminated amniotic fluid because lamellar bodies can be affected by contaminants and there isn’t as strong standardization or universal cutoff guidance for this test. That’s why it’s often considered supplementary rather than the most valid marker in these circumstances. More robust and widely validated markers in contaminated samples are the lecithin/sphingomyelin ratio and phosphatidylglycerol, which have clearer interpretation and stronger clinical validation. The surfactant/albumin ratio can also be used, but it doesn’t supersede L/S or PG in reliability. So lamellar body count is sometimes evaluated, but it’s not identified as the best marker when the amniotic fluid is contaminated.