Does my wife have to wait until after she misses her period to take a pregnancy test?

Yes. Only some over the counter pregnancy tests claim to work within the first day of a missed period. Most work within a week of the missed period. The test is measuring for the hCG hormone, and the longer you can wait, the higher the hormone levels, and the more chance you'll get an accurate result.































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If you see your doctor a blood test can be done for free if you have medicare and it can read it from 7 day's which is most likely the earliest test you can have

Before you decide when to take a pregnancy test, it helps to understand how they work. The tests detect pregnancy hormone, human chorionic gonadotropin (hCG), in your urine. Some tests also detect a variation of this hormone, known as hyperglycosylated hCG (H-hCG).
Most women take a home pregnancy test (HPT) when they have a pregnancy symptom or two. For many women the first pregnancy symptom is usually a missed period. You may have other pregnancy symptoms as well. Pregnancy tests are usually good at the minimum on the first day that you miss your period.