Test Details
Methodology
Electrochemiluminescence immunoassay (ECLIA)
Result 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.
Use
Immunoassay for the in vitro quantitative determination of the sum of human chorionic gonadotropin (hCG) plus the hCG beta-subunit in human serum and plasma.1 This assay is intended for the early detection of pregnancy.
Special Instructions
Values obtained with different assay methods should not be used interchangeably in serial testing. It is recommended that only one assay method be used consistently to monitor each patient's course of therapy. This procedure does not provide serial monitoring; it is intended for one-time use only. If serial monitoring is required, please use the serial monitoring number 480038 to order.
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.
Limitations
As with all tests containing monoclonal mouse antibodies, erroneous findings may be obtained from samples taken from patients who have been treated with monoclonal mouse antibodies or have received them for diagnostic purposes.1 In rare cases, interference due to extremely high titers of antibodies to streptavidin and ruthenium can occur.1 The test contains additives, which minimize these effects.
Footnotes
Custom Additional Information
Similarly to LH, FSH, and TSH, human chorionic gonadotropin (hCG) is a member of the glycoprotein family and consists of two subunits (α and β chains) that are associated to the intact hormone.1-7 The α-chains in all four of these glycoprotein hormones are virtually identical, whereas the β-chains have greatly differing structures and are responsible for the respective specific hormonal functions.
hCG is produced in the placenta during pregnancy. In nonpregnant women, it can also be produced by tumors of the trophoblast, germ cell tumors with trophoblastic components, and some nontrophoblastic tumors.
Human chorionic gonadotropin consists of a number of isohormones with differing molecular size. The biological action of hCG serves to maintain the corpus luteum during pregnancy. It also influences steroid production. The serum of pregnant women contains mainly intact hCG.
Measurement of the hCG concentration permits the diagnosis of pregnancy just one week after conception. The determination of hCG in the first trimester of pregnancy is of particular importance. Elevated values here serve as an indication of chorionic carcinoma, hydatiform mole, or multiple pregnancy. Depressed values indicate threatening or missed abortion, ectopic pregnancy, gestosis, or intrauterine death.
Elevated hCG concentrations not associated with pregnancy are found in patients with other diseases, such as tumors of the germ cells, ovaries, bladder, pancreas, stomach, lungs, and liver.6,7
Specimen Requirements
Specimen
Serum (preferred) or plasma
Volume
1 mL
Minimum Volume
0.7 mL (Note: This volume does not allow for repeat testing.)
Container
Red-top tube, gel-barrier tube, or green-top (lithium heparin) tube. Do not use oxalate, EDTA, or citrate plasma.
Collection Instructions
If a red-top tube or plasma is used, transfer separated serum or plasma to a plastic transport tube.
Stability Requirements
Temperature | Period |
|---|---|
Room temperature | 14 days |
Refrigerated | 14 days |
Frozen | 14 days |
Freeze/thaw cycles | Stable x3 |
Reference Range
See table.
Range (mIU/mL) | |
|---|---|
Weeks of pregnancy is defined as completed weeks beginning with the start of the last menstruation phase. | |
Male | 0−3 |
Female | |
nonpregnant | 0−5 |
postmenopausal | 0−8 |
pregnant | |
Weeks Gestation | |
3 | 6−71 |
4 | 10−750 |
5 | 217−7138 |
6 | 158−31,795 |
7 | 3697−163,563 |
8 | 32,065−149,571 |
9 | 63,803−151,410 |
10 | 46,509−186,977 |
12 | 27,832−210,612 |
14 | 13,950−62,530 |
15 | 12,039−70,971 |
16 | 9040−56,451 |
17 | 8175−55,868 |
18 | 8099−58,176 |
Storage Instructions
Room temperature
Causes for Rejection
Citrate plasma specimen; improper labeling
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 004416 | hCG,Beta Subunit, Qnt | 45194-8 | 004417 | hCG,Beta Subunit,Qnt,Serum | mIU/mL | 45194-8 |
| Order Code | 004416 | |||||
| Order Code Name | hCG,Beta Subunit, Qnt | |||||
| Order Loinc | 45194-8 | |||||
| Result Code | 004417 | |||||
| Result Code Name | hCG,Beta Subunit,Qnt,Serum | |||||
| UofM | mIU/mL | |||||
| Result LOINC | 45194-8 |