Urine pregnancy test
- By Dr. T Deepa Porkodi
When you get pregnant, the body produces a hormone called the Human Chorionic Gonadotropin, commonly known as the HCG.
This UPT test involves using a dipstick, or a test strip, that is dipped into urine.
Alternatively, it may also be a kit that involves collecting urine, and adding drops of it into the kit.
High levels of HCG, though most commonly found in pregnancy, can also be due to certain tumors.
If HCG is present, the kit shows a band of color change. This means you are pregnant. In case the colored band doesn’t appear, it shows that you are not pregnant.
The test results have to be interpreted after waiting for a period of 5 minutes. Beyond that time, the test results cannot be considered valid.
Each kit will have a specifically designed control band, that always changes color. This is present to check the functionality of the kit. If the control band does not appear to change color, the kit might be a faulty one.
Once the fertilization occurs in the Fallopian Tube, it takes about 9 days for the fertilized egg to implant itself on the uterine wall. The placenta then develops around it, and begins to release HCG into the blood. Some amount of HCG also finds its way into the urine. The amount of HCG in the urine is initially low, but it doubles in 2 to three days.
Most UPT kits detect pregnancy about a week after the missed period. Some highly sensitive kits can also detect the presence of HCG as early as a day after the missed periods.
UPT kits are a simple, hassle free way of getting to know whether you are pregnant or not.
Early morning urine is the best sample for testing.
The accuracy of home pregnancy tests is different for every woman because:
- The days of a woman's menstrual cycle, and ovulation can change each month.
- The exact day of implantation of the fertilized egg is not always known.
- Each home pregnancy test kit has a different sensitivity. If the HCG level is very low, the first urine of the morning is most likely to show a positive result.