A test used to determine whether conception has occurred. In addition to the clinical signs and symptoms of pregnancy, almost none of which are reliable within the first several weeks of pregnancy, chemical tests done in the physician’s office are quite accurate by as early as the time the first menstrual period is missed. There are also test kits available for purchase without a prescription. If over-the counter tests are used, it is very important to follow the directions carefully.
Examinations of urine or blood are conducted to ascertain pregnancy in women. Pregnancy test kits can be purchased directly from pharmacies without the need for a prescription.
All the kits are formulated to examine the presence of human chorionic gonadotrophin (HCG) in a urine sample. This hormone is typically generated by a developing placenta. The tests exhibit a high level of accuracy (approximately 97 percent for a positive result and 80 percent for a negative result) and can be consistently employed starting from the initial day after a missed period. Nonetheless, the test can potentially yield incorrect results in situations involving a hydatidiform mole, due to exceptionally elevated HCG levels.
Various types of pregnancy tests differ, but they all entail placing a urine sample onto a test strip coated with a chemical designed to interact with HCG. Blood-based pregnancy tests, which can identify pregnancy from 9 to 12 days after conception (prior to a missed period), are also an option.