Pregnancy testing
How to Use a Home Urine Pregnancy Test
Home pregnancy tests detect human chorionic gonadotropin (hCG) in urine. Follow these best practices to ensure accurate results and know when to seek medical confirmation.
How to Use This Guide
- Choose a test and verify it has not expired.
- Follow the manufacturer’s instructions exactly.
- Interpret results within the indicated time window; confirm with a healthcare provider when needed.
Formula
Detection limit (mIU/mL) varies by brand (commonly 10–25 mIU/mL).
Odds of detection increase daily after implantation: hCG roughly doubles every 48 hours.
Testing at or after the first missed period yields ≥99% accuracy per manufacturer data.
Full Description
Most home tests involve collecting urine midstream or dipping the test strip in a sample. Results display as lines, digital words, or symbols within 1–5 minutes. Use first-morning urine for highest hCG concentration, especially before a missed period.
False negatives result from testing too early, diluted urine, expired tests, or not waiting the full reaction time. False positives are rare and typically caused by recent fertility treatments or certain medical conditions. Always confirm unusual results with a healthcare provider, particularly if you have bleeding, pain, or inconsistent outcomes.
Frequently Asked Questions
When is the best time to take the test?
Test on or after the first day of your missed period using first-morning urine for highest accuracy.
What if the result line is faint?
A faint positive still indicates hCG. Repeat in 48 hours to confirm that the line darkens as hCG rises.
Can medications interfere?
Most medications do not affect results. hCG-containing fertility injections can yield false positives for up to 14 days.
How do evaporation lines differ from positives?
Evaporation lines appear after the recommended reading time and usually lack color. Only read the result within the specified window.