You can have a positive result taking a pregnancy test 12 to 14 days after ovulation.
More Info: For the most accurate results, you should wait until the first day of a missed period to take a pregnancy test. Conception can occur soon after ovulation, however the egg must travel and implant itself into the uterus for it to be a viable pregnancy. This could take up to a week after conception.
Are there pregnancy tests that can be done sooner than 12 to 14 days?
There are some over the counter pregnancy tests that can be used a few days before your menstrual cycle should start, however, waiting a few more days is recommended. Once the egg is implanted, you body will start producing a hormone called hCG (Human Chorionnic Gonadotropin). There needs to be enough hGC in your system to get an accurate reading with any type of pregnancy test.
“Sperm: How long do they live after ejaculation? – MayoClinic.com.” Mayo Clinic medical information and tools for healthy living – MayoClinic.com. N.p., n.d. Web. 16 Apr. 2010. http://www.mayoclinic.com/health/pregnancy/AN00281.
“The Menstrual Cycle and Ovulation.” NetWellness Homepage. N.p., n.d. Web. 16 Apr. 2010. http://netwellness.uc.edu/healthtopics/pregnancy/pregmenstrualcycle.cfm.