A positive pregnancy test confirms a pregnancy but cannot precisely locate it. Pregnancy tests detect the hormone hCG. The hCG levels in cases of ectopic pregnancy are lower than in normal pregnancies, so a false-negative results is possible. To avoid a false-negative test, you should use the more specific, blood-based pregnancy test (beta). In cases of ectopic pregnancy, not only are the hCG-levels lower than normal, but also the hCG-level increases more slowly than during a normal pregnancy. In a normal pregnancy, the hCG-level doubles every 24 hours in the first weeks of pregnancy. In the case of an ectopic pregnancy, the increasing of hCG-levels are less than 66% over 48 hours. The location of an ectopic pregnancy can be determined with an ultrasound, but not always. Normal (uterine) pregnancies can be confirmed with ultrasound in the 5th week of pregnancy. Tubal ectopic pregnancies can’t be seen with an ultrasound before the 7th week of pregnancy . Therefore, in some cases, a laparoscopy will be requested to find the embryo. Chances of having a repeated ectopic pregnancy are 15%.