A urine pregnancy test is used as an initial screening test for pregnancy and more rarely, for the investigation of certain pathological conditions such as choriocarcinoma.
Human chorionic gonadotropin (hCG) is a hormone secreted by the placenta of the fertilized egg implanted in the uterine wall. Thus, the measurement of chorionic gonadotropin is useful in determining pregnancy. Chorionic gonadotropin is produced as pregnancy progresses, resulting in elevated blood levels. A significant amount of chorionic gonadotropin, in the form of alpha and beta subunits, is excreted in the urine. The beta subunit is the most sensitive indicator of pregnancy.
The urine pregnancy test is usually positive within 5-7 days of conception. Pregnancy tests are generally considered to be about 98% accurate. If the test is negative but pregnancy is still suspected, the test should be repeated in 1 week.
Positive pregnancy test: Pregnancy, choriocarcinoma, ectopic pregnancy, fetal carcinoma, molar pregnancy, testicular cancer. Medications that may cause a false positive: Antiepileptics, antiparkinsonian, hypnotic, sedative, and phenothiazines
Negative pregnancy test: Abortion (threatened, real), ectopic pregnancy. The presence of hematuria or proteinuria can cause false-negative results. False-negative results can also occur if the test is done too early in pregnancy. The test should be carried out no earlier than 5 days after the first day of expected menstruation.
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. The correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings, and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.