The Clearblue Pregnancy Test with Colour Change Tip is quick and easy to use, producing an accurate result in just 2 minutes and now gives you the option to test up to 4 days early! It is the only test to give you 7 signs of certainty. Clearblue Pregnancy Test with Colour Change Tip is quick, easy and effective to use - providing you with accurate results in as little as 2 minutes. This quick and clever pregnacy test works by detecting the level of hormones in your urine and is proven to be 99% effective and accurate. This product is the most recommended by doctors/pharmacists.