The two hormones which 'drive' the growth of the follicles in ovary are Follicle Stimulating Hormone (or FSH) and Luteinising Hormone (or LH). Both these hormones work in tandem leading to the follicle growth that culminates in the release of egg (ovulation) from the ovary.
In order to induce ovulation artificially, there are two ways: tablets and injections. The tablets (commonest being Clomiphene) do not directly stimulate the ovary, these cause the brain to release FSH and LH at exaggerated levels. The injections on the other hand directly stimulate the ovaries. In the vast majority of women, FSH injections suffice for stimulation.
- human Menopausal Gonadotrophins (hMG): purified from natural sources (urine of menopausal women)
- Recombinant FSH (r-FSH): synthesized using technology (Recombinant DNA technology)