Baby Settling In: Implantation of the Egg
"Implantation" is a colloquial yet accurate term for the action an ovum, or egg, takes after being fertilised. When a woman ovulates, her egg begins a slow trip down the fallopian tubes, where it waits to be fertilised. If the egg is penetrated by sperm, it travels down into the uterus and implants itself in the endometrial lining, triggering an eruption of chemical changes inside the female body and inside the egg itself.
However, this journey can take several days to a week to complete. For this reason, trying an early pregnancy test at this stage may yield falsely negative results. Testing should be done at least one week after ovulation, or whenever the woman notices her period is late or absent.
When Do You Know?
Most early pregnancy test advertisements claim accuracy and early results above all else, yet only rarely are these claims true. Accuracy of early pregnancy test results depends on correct use of the test, as well as the test being free of defects and flaws, and numerous other variables beyond the control of the test's manufacturers or the person taking the early pregnancy test. Being outside a clinical environment makes it nearly impossible to control the circumstances under which the early pregnancy test is taken.
Secondly, while early results can be exciting and at times reassuring, they may lead to regret if the pregnancy doesn't last, if the results turn out to be inaccurate, or if the pregnancy is unwanted. Taking a pregnancy test is a difficult and dreadful thing for most women, whether they're afraid of it being positive or negative; knowing the results sooner is not always better.
All of that aside, most tests claim accurate results within one week. This is assuming that 1) the woman taking the early pregnancy test ovulates on a regular basis, and 2) the fertilised ovum has already settled into its new home in the uterus and begun producing human Chorionic Gonadotropin, the hormone the early pregnancy test will measure to determine pregnancy.
Most pregnancy tests, even those marketed as an early pregnancy test, cannot detect an amount of hCG less than 20mlU/mL; and some women may not produce that much until they've been pregnant for about two to three weeks. Your doctor can run a quantitative blood test, capable of detecting hCG levels as low as 1 mlU/mL. Having a quantitative blood test done approximately six to twelve days after fertilisation is probably your best bet for accurate and error-free testing.
In short, while getting an early pregnancy test done is not a bad idea, it would be unwise to put your total trust in the results. Try testing again a week later, or following up with your doctor for a clinical early pregnancy test. Under clinical conditions, there is a much smaller margin of error on any medical testing; and pregnancy is one medical condition you certainly want recognized and diagnosed as soon as possible.
