It is fine when the pregnancy test paper does not deepen due to the short time of embryo implantation, but it is not fine when it is caused by biochemical pregnancy or preterm miscarriage. Early pregnancy test is a simple and effective way to detect whether you are pregnant or not, when the embryo is short, it will not deepen the indication line of the early pregnancy test, which is generally fine, and you can follow the doctor’s advice to check again. However, when a biochemical pregnancy or preterm miscarriage occurs, the test paper will not deepen, which will lead to pregnancy failure, and there is something wrong. Biochemical pregnancy is caused by unsuccessful implantation of the embryo caused by blood HCG (human chorionic gonadotropin) transient elevation, appear similar to menstruation vaginal bleeding, pregnancy test paper does not deepen, do not need to deal with. However, when abdominal pain, vaginal bleeding and other symptoms of pre-eclampsia occur, due to the low level of blood HCG can also lead to the test paper does not deepen, to follow the doctor’s advice to give progesterone and other drugs to treat.