Understanding Your Laboratory Test: What It Is, Why It Is Done, and What the Results Mean

This test is a laboratory procedure in which a small sample of your blood, urine, or other body material is analyzed to measure specific substances, cells, or markers that show how your body is functioning and whether illness may be present.

The 3-Hydroxytetradecanoylcarnitine (C14-OH) test measures the amount of a specific fatty acid metabolite called C14-OH acylcarnitine in the amniotic fluid that surrounds the baby during pregnancy. Acylcarnitines are substances produced when the body breaks down fats for energy. This test uses a sample of amniotic fluid collected during amniocentesis, a procedure where a small amount of fluid is removed from the uterus for testing.

Your doctor may order this test as part of a routine health checkup, to investigate symptoms such as fatigue, pain, or fever, to help diagnose a medical condition, to monitor a chronic disease, or to track how well a treatment is working over time.

This test is performed to screen for certain metabolic disorders that a baby may have before birth. These disorders affect how the baby's body processes fats for energy. Detecting these conditions during pregnancy allows healthcare providers to prepare for special care the baby may need immediately after birth. The test is usually ordered when there is a family history of metabolic disorders or when other screening tests suggest a potential problem.

Your results are compared with normal reference ranges, and values within those ranges usually suggest typical body function. Out-of-range values may point to infection, inflammation, anemia, hormone imbalance, or another condition, but they do not provide a diagnosis by themselves. Your doctor will interpret the numbers along with your symptoms, medical history, and other test results, and will explain what the findings mean for you and whether follow-up testing or treatment is needed.

Abnormally high levels of C14-OH acylcarnitine in amniotic fluid may indicate that the baby has a disorder affecting fatty acid oxidation, such as multiple acyl-CoA dehydrogenase deficiency (MADD) or long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHAD). These are rare but serious conditions that affect how the body converts fat into energy. Your healthcare provider will interpret these results in combination with other test results and discuss any necessary follow-up steps with you.