The A fertilization process comprises includes the following steps: a) a container (15) which can be introduced into, and lodged in, the uterine cavity of the mammal is provided; b) the container (15) is filled with a culture medium, at least one ovocyte of the mammal, and spermatozoa; c) the filled container (15) is inserted into the uterine cavity; d) the container (15) is left for a given length of time to allow fertilization of the ovocyte(s) to take place; e) the contents of the container (15) are released into the uterine cavity. The container may be made from a tube of biodegradable or non-biodegradable material. In the latter case, it is associated with a stiffening device. A biodegradable container (15) filled with gametes and a culture medium is placed in the uterine cavity using an implantation device (20) which is then withdrawn from the mammal's genital tract.