Human Chorionic Gonadotropin (hCG), β-Subunit, Quantitative CPT: 84702
Special Instructions
This test may exhibit interference when sample is collected from a person who is consuming a supplement with a high dose of biotin (also termed as vitamin B7 or B8, vitamin H, or coenzyme R). It is recommended to ask all patients who may be indicated for this test about biotin supplementation. Patients should be cautioned to stop biotin consumption at least 72 hours prior to the collection of a sample.
Expected Turnaround Time
Within 1 day
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Specimen Requirements
Specimen
Serum
Volume
0.8 mL
Minimum Volume
0.3 mL (Note: This volume does not allow for repeat testing.)
Container
Red-top tube or gel-barrier tube.
Collection
If a red-top tube is used, transfer separated serum to a plastic transport tube.
Storage Instructions
Room temperature
Stability Requirements
Patient Information
To confirm a pregnancy; to help identify an ectopic pregnancy; to monitor a pregnancy that may be at risk of failing; occasionally to screen a woman for pregnancy prior to some medical treatments; as part of a panel of tests used to screen for fetal abnormalities (see First Trimester Down Syndrome Screen and Second Trimester Maternal Serum Screening)
When you suspect that you are pregnant (testing can be done reliably by 10 days after you miss your menstrual period and some methods can detect hCG even earlier); when you have signs and symptoms that suggest you may have an ectopic pregnancy or a pregnancy that is failing; prior to some medical treatments.
A urine sample, preferably collected first thing in the morning, or a blood sample drawn from a vein in your arm.
Do not drink large amounts of fluid before collecting a urine sample for a pregnancy test because overly diluted urine may result in a false negative; no preparation is needed for a blood sample.