This serves to stimulate the ovaries to form several follicles within a monthly cycle in order to obtain several fertilisable eggs.
This increases the probability of achieving egg fertilisation after intercourse or insemination. In the course of IVF or ICSI treatment, up to three embryos may be transferred back into the uterine cavity (embryo transfer) to increase the chances of pregnancy. To achieve this, it is also advantageous to have as many fertilisable eggs as possible available for IVF or ICSI, as not all of them are usually fertilised. The resulting surplus fertilised eggs can be frozen (cryopreserved) for further transfers if desired.