Sign in →

Test Code UHCGSC Pregnancy, Urine, LAB437

Performing Laboratory

St. Luke's Hospital Cedar Rapids

Specimen Requirements

Preferred: Urine should be collected in a clean and dry container. A first morning urine is preferred since it generally contains the highest concentration of hCG; however, a random specimen may be used. Urine specimens exhibiting visible precipitates should be centrifuged prior to testing.

Specimen Volume: 0.2 mL of urine

Stability: Samples may be stored up to 48 hours at 2-8º C, or frozen for prolonged storage.  Thawed samples should be mixed before testing.
Collection Instructions: 
Note: 1. Specimens from patients who have received preparations of monoclonal antibodies for diagnosis or therapy may contain HAMA. Such specimens may cause false positive or false negative results.

2. False negative results may occur when the levels of hCG are below the sensitivity level of the test. When pregnancy is still suspected, a serum specimen should be collected 48 hours later and tested.

3. Very low levels of hCG (less than 50 mIU/mL) are present in serum and urine shortly after implantation. However, because a significant number of first trimester pregnancies terminate for natural reasons, a test result that is weakly positive should be confirmed by retesting with a serum specimen collected 48 hours later.

4. A number of conditions other than pregnancy, including trophoblastic disease and certain nontrophoblastic neoplasms including testicular tumors, prostate cancer, breast cancer, and lung cancer, cause elevated levels of hCG. Therefore, the presence of hCG in serum should not be used to diagnose pregnancy unless these conditions have been ruled out.

5. This test provides a presumptive diagnosis for pregnancy. A confirmed pregnancy diagnosis should only be made by a physician after all clinical and laboratory findings have been evaluated.

Reference Values

Females, nonpregnant: negative

Useful For

The appearance of hCG in both serum and urine soon after conception, and its subsequent rapid rise in concentration during early gestational growth, make it an excellent marker for the early detection of pregnancy.

Day(s) Test Set Up

Monday through Sunday

Methodology

Rapid Chromatographic Immunoassay

Test Classification and CPT Coding

84703