In the first step of pregnancy, sperm and egg must meet and unite to form an embryo; while the embryo is developing, the endometrium is actively preparing to welcome the embryo; when the embryo and the endometrium are developing at the same pace, the blastocyst and the endometrium in a receptive state come into further intimate contact, and eventually the blastocyst burrows into the endometrial layer, and the embryonic trophoblast establishes a close connection with the endometrium, which is the embryo If an abnormality occurs at some point before this connection is established, the embryo will not be able to settle and, of course, pregnancy will not be possible. A biochemical pregnancy is an early stage of a normal pregnancy. A biochemical pregnancy is a term that refers specifically to the natural termination of the embryo before the formation of the gestational sac, and possibly to an ectopic pregnancy (ectopic) miscarriage. A “biochemical pregnancy” means that your little angel has been here before, but only for a short time and then left quietly. If a single biochemical pregnancy or miscarriage is fortuitous, you can continue trying to conceive; if you have multiple biochemical pregnancies, especially if you are pregnant after IVF treatment, you need to seek help from your doctor to find the cause.