Most moms carrying twins go into labor at 36 to 37 weeks, as opposed to 40 in a single pregnancy, Al-Khan says, and some may go even earlier. Generally, if the twins are born after 34 weeks, there should not be a major concern, but a premature baby is still a premature baby, he says.
False pregnancy in humans is less common, and may sometimes be purely psychological. It is generally believed that false pregnancy is caused by changes in the endocrine system of the body, leading to the secretion of hormones that cause physical changes similar to those during pregnancy.
If you get a false positive from a home pregnancy test, it is usually the result of faulty test strips. Most home pregnancy tests now have an indicator that shows whether or not the test is working correctly. If you leave your pregnancy test too long before checking it, this can also cause a false positive.