The Clearblue Pregnancy Test with Weeks Indicator is the first and only test that is as accurate as an ultrasound scan at dating pregnancy2. Its Smart Dual Sensor ™ not only tells you in words if you're 'Pregnant' or 'Not Pregnant', also tells you how far along you are.
So sensitive you can test up to 5 days before your missed period3.
Other fertility therapies (such as clomiphene citrate), painkillers and hormonal contraceptives (e.g. contraceptive pill) should not affect the result.
If you have recently stopped using hormonal contraception or are using fertility therapies like clomiphene citrate, your periods may be irregular, leading you to test too soon.
Reviewed by Dr Joanna Pike on Apr 26, 2017
Weeks' result 97% in agreement with later ultrasound dating scan. Based on studies of 187 women comparing results (1-2, 2-3, 3+ weeks since conception) to ultrasound dating.
Can be used 5 days before your missed period (which is 4 days before your expected period). In lab testing, 98% of pregnant results were detected the day before the expected period, 97% were detected 2 days before, 90% 3 days before and 65% 4 days before the expected period.