You can generally take a pregnancy test from the first day of your missed period for the most reliable result. If you don’t know when your period is due, it’s recommended to wait at least 21 days (about three weeks) after unprotected sex before testing
. Some very sensitive pregnancy tests claim to detect pregnancy a few days before a missed period, but these are less accurate and may give false negatives if taken too early
. Pregnancy begins only after fertilization and implantation, which can take up to 2-3 weeks after unprotected sex. It takes time for your body to produce enough human chorionic gonadotropin (hCG) hormone for a test to detect-usually 10-14 days after conception
. In summary:
- Earliest reliable testing: first day of missed period or about 2 weeks after unprotected sex
- If period date unknown: test at least 21 days after unprotected sex
- Testing too early may lead to false negatives due to insufficient hCG levels
- Some sensitive tests can detect pregnancy a few days before missed period but with lower accuracy
Waiting until the appropriate time improves the accuracy of home pregnancy tests significantly
