At the beginning of an IVF treatment cycle, the ovaries are stimulated. In contrast to the natural cycle, hormonal treatment facilitates the development of several oocytes. The mature oocytes are harvested by puncturing the ovaries, in order to be fertilised subsequently.
It is important to safely gather as many oocytes as possible, because not every oocyte is able to be fertilised. In order to obtain embryos of a high quality, a sufficient number of oocytes must be fertilised.
Which hormone therapy is selected is decided according to individual aspects, which ensures the adequate fertilisation of oocytes.
Generally, two types of medication are administered:
~ The follicle-stimulating hormone FSH (product names are Menogon HP, Puregon and Gonal F), which are identical to the natural, human FSH. The administration of FSH is intended to promote the development of several oocytes in the ovaries.
~ The second drug (medication) – which is marketed under many names - is intended to prevent premature ovulation, which needs to be avoided in IVF treatment.
The ovarian reaction to the drugs is controlled via ultrasound. In most cases, two to three ultrasound examinations are necessary in order to time the oocyte puncture/extraction perfectly.