Twin: One of two children produced in the same pregnancy. Twins can develop from one ovum (egg) or from two ova (eggs). Twins who develop from a single ovum are called monozygotic or identical twins. They have identical genomes. Twins who develop from two ova that are fertilized at the same time are called dizygotic or fraternal twins. They are nonidentical and have different genomes.
Unfortunately, many women have a small amount of this hormone continuously and if the level gets high enough just before a period, you could get a false pregnancy test result. The best time to use a urine test for pregnancy is three to five days after your missed period.
Despite a negative test result, itâs very possible that you are pregnant, but the hCG levels are too low for a test to accurately detect it. Another cause of false-negative pregnancy test results is erratic or improper testing techniques. Most test sticks need to be saturated in urine to get accurate results. If you do not leave your test strip in the urine long enough, it could give you false negative or false positive pregnancy test results. Check the date on the pregnancy test before purchasing it. Out-of-date tests will not give you results you can trust. Also remember that certain fertility medications and rare medical conditions may affect the results of pregnancy tests, and false negatives could be more common in these situations.