The diagnosis of pregnancy is accurately made by urine pregnancy testing and using blood serum. Current urine testing kits are highly specific and detect 35-30 mIU of HCG (human chorionic gonadotropin, the pregnancy hormone) per ml of urine.
Urine Based
- Collect a fresh urine specimen. A specimen first thing in the morning is preferable in early pregnancy because the hormone is more concentrated and more likely to be positive if only a small amount of HCG hormone is present.
- Place the correct number of drops of urine in the collecting area of the test kit. The precise number of drops varies from manufacturer to manufacturer.
- Wait the length of time specified by the manufacturer.
- After approximately 3 minutes the test is read. A blue line next to the "Control Line" (C) indicates that the urine has turned the control area positive. This means the test kit is working correctly.
- Because there is no visible "+" in the pregnancy test area (T), the test results are negative...the patient is not pregnant.
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In this test 3 drops of urine are placed in the "S" basin, a sold line appears at the "C" area (indicating the test is working). After 3 minutes another line appears at the "T" area, indicating that this patient is pregnant.
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Blood Serum
In an urgent situation, or if a patient is unable to provide urine for the test, blood serum can be used in the test kit
This is an imperfect solution, because the forms of HCG (pregnancy hormone) found in serum are somewhat different from the forms found in urine.
Further, the serum proteins tend to sludge up the test kit, both mechanically and biochemically. That said, using serum instead of urine will work well enough for most purposes and can provide immediate insight into the patient's problem.
- Draw blood into a test tube.
- Tape the test tube to the wall for about 10 minutes (allow it to clot).
- Using an eye dropper or a syringe with a needle, draw off a small amount of serum (the clear, watery part of the blood that's left at the top of the test tube after the blood has clotted).
- Use the serum instead of urine in the urine pregnancy test kit, drop for drop. If the test kit calls for 4 drops of urine, use 4 drops of serum.
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