At this stage of prenatal development, the conceptus is called a blastocyst. Between the stages of fertilization and implantation, the developing human is a "preimplantation conceptus". The conceptus includes all structures that develop from the zygote, both embryonic and extraembryonic. The conceptus is then known as the blastocyst. A conceptus between fertilization and implantation is also frequently classified as an embryo. Then as the conceptus develops expression will increase, which is likely to promote embryo development. After implantation, EPF may be produced by the conceptus directly. E-cigarette aerosols without containing nicotine could harm the growing conceptus. This seems to preclude further development of the vascular network of the conceptus. Conceptus was acquired by Bayer AG of Germany in June 2013.