A urine pregnancy test can typically detect pregnancy 12–14 days after ovulation, which is usually 1–2 weeks after conception. Most tests are most reliable from the first day of a missed period onward. Early detection tests may work a few days before a missed period, but accuracy improves as hormone levels rise. The hormone detected is human chorionic gonadotropin (hCG), which doubles approximately every 2–3 days in early pregnancy. Testing too early can result in a false negative. Factors affecting detection timing include the sensitivity of the test, the regularity of your cycle, and when implantation occurs—which can vary by several days. For the most accurate result, take the test after a missed period, ideally in the morning when urine is most concentrated. If you test early and get a negative result but still suspect pregnancy, retesting a few days later is recommended. Blood tests can detect pregnancy slightly earlier than urine tests because they can measure lower levels of hCG.