Complete Blood Count (CBC): What Patients Need to Know

The complete blood count, commonly called a CBC, is a routine blood test that measures the different cells in your blood, including red blood cells, white blood cells, hemoglobin, hematocrit, and platelets, giving your care team a broad picture of your overall health.

The C6-DC test measures two specific substances called acylcarnitines—adipoylcarnitine and methylglutarylcarnitine—in the amniotic fluid that surrounds the baby during pregnancy. These compounds are markers that can indicate whether a fetus has certain inherited metabolic disorders, particularly problems with how the body breaks down fats and proteins for energy.

Your doctor may order this test as part of a routine checkup, to help diagnose conditions such as anemia, infection, inflammation, or certain blood disorders, or to monitor how a treatment or ongoing illness is affecting your body over time.

This test is typically performed when there is a family history of metabolic disorders, abnormal results from routine prenatal screening, or when parents are known carriers of certain genetic metabolic conditions. It helps healthcare providers detect potential problems early in pregnancy, sometimes as early as the second trimester, allowing for better planning and early treatment options after birth.

The test is done with a simple blood draw: a healthcare provider cleans the skin on your arm, wraps a band around your upper arm, and collects a small sample of blood from a vein, usually on the inside of your elbow; the sample is then sent to a laboratory for analysis, and the whole process typically takes only a few minutes.

A healthcare provider collects a small sample of amniotic fluid through a procedure called amniocentesis, where a thin needle is inserted into the uterus under ultrasound guidance. The sample is then sent to a laboratory where specialized equipment measures the levels of C6-DC acylcarnitines. The procedure carries a small risk of miscarriage, so it is usually only done when medically necessary.

Your results show whether each type of blood cell falls within the normal range; values that are too high or too low may point to conditions such as infection, anemia, dehydration, or clotting problems, and your doctor will interpret them together with your symptoms, medical history, and other test findings before recommending any next steps.

Normal levels of C6-DC in amniotic fluid suggest the baby likely does not have the specific metabolic disorders this test screens for. Elevated levels may indicate the fetus has a fatty acid oxidation disorder or an organic acidemia, such as multiple acyl-CoA dehydrogenase deficiency (MADD) or glutaric acidemia type II. However, abnormal results require further confirmatory testing and genetic counseling to determine the exact condition and severity.