Pregnancy Tests: The Facts and Their Sensitivity Levels

There are two types of pregnancy tests: Blood Serum and Unine. The blood serum pregnancy test is usually performed in a hospital lab or doctor’s office. The urine test can be performed in a laboratory or at home using a home pregnancy test (hpt). The blood serum test can measure the pregnancy hormone, human chorionic gonadotropin (hcg) at 5 – 10 mIU/ml and the urine test can detect the hcg hormone at 25 – 50 mIU/ml, so the blood serum is more sensitive than the urine test and can detect a pregnancy earlier than a urine test can. There are two types of urine tests. Follow directions on the test label/box. Some require a stick to be placed in a midstream of urine, some require to be dipped in a sample of urine for a certain amount of time.

There are two tests that can be performed: Qualitative and Quantitative. The qualitative pregnancy test is used to measure whether or not hcg is present. The quantitative hcg test is performed when the amount of hcg is desired to be known. High levels of hcg could signal the presence of more than one fetus. Hcg levels rise during the first trimester and level off and even drop off after the first trimester.

Levels of HCG can be detected 1 or 2 days after implantation for both urine and blood serum pregnancy tests. This is roughly 10 days after the woman has ovulated. If a woman is using OPK’s to test for ovulation or using a charting method to detect ovaluation, she could start testing at roughly 10 days past ovaluation (10 dpo) with sensitive home pregnancy tests.

Pregnancy tests are performed because a woman is late for her menstrual flow/period. A test may also be performed when she suspects she is pregnant but is not yet late for her period. A doctor may also routinely perform a pregnancy test when a woman is about to have a test or surgery that could harm a fetus if she is pregnant. In this case, the test is performed to rule out a pregnancy. A doctor may also perform a pregnancy test if a woman presents herself at an appointment complaining of symptoms of early pregnancy, including an enlarged uterus upon examination, flu-like symptoms, frequent urination or lack of menstrual period.