Profasi is Human Chorionic Gonadotrophin (HCG). This is the hormone that the developing embryo, and later the placenta, make when you become pregnant. It is also the hormone that we test for when we perform a pregnancy test. The reason why it is given as a fertility treatment is to stimulate ovulation.
Normally, the pituitary gland emits a surge of the hormone LH (luteinising hormone) to stimulate ovulation, but LH is not available to give as an injection. Therefore we give HCG, which is chemically very similar and has the same effect as LH.
HCG stays in your system for at least a fortnight and as modern pregnancy tests are very sensitive, it can lead to a false positive pregnancy test for at least this length of time. A pregnancy test shouldn’t be done for at least three weeks after taking Profasi.