What is the earliest time a pregnancy be detected and when can a blood test detect the pregnancy?

If a woman has cycles that are NOT 28 days, then this information will not be accurate. Generally speaking, a positive on a home pregnancy test can appear up to five days before you MISS your period, so that would be FOUR days before your period is due - again, this assuming you have a 14 day luteal phase (the time between ovulation and menstuation). What does this mean? It is possible that some tests will pick up a positive at 10 days post-ovulation. It is uncommon, but some women have gotten a positive result a day or two earlier than this. Most women will NOT experience a positive result until after they have missed their period. A doctor's urine test is no more accurate than an over-the-counter pregnancy test, but a blood beta would be able to detect pregnancy a day or two sooner than a urine test.