1. Hormonal stimulation
The chances of success in IVF treatment increase significantly if several eggs are matured simultaneously (usually by means of hormone treatment). If this is no longer possible or not desired (due to a later stage in life, a limited egg reserve, sensitivity to hormones), IVF treatment cycles can also be carried out with one or only a few eggs (‘mild stimulation IVF’).
2. Eggs are removed and prepared
As soon as the eggs are mature, the doctor uses a delicate needle to remove them from the ovaries with ultrasound guidance. This procedure is called follicular aspiration. It usually takes only a few minutes. The woman may be given a mild sedative for the procedure. The retrieved eggs are then prepared for fertilisation in the laboratory.
3. Sperm sample from the man
The sperm from the man’s sperm sample are prepared in the laboratory. In the process, the motile sperm are separated from the non-motile and dead sperm. If no sperm are found in the ejaculate, material from a testicular biopsy (TESE) can also be used. If the partner has no sperm capable of fertilisation, cryopreserved sperm material from a sperm bank (donor sperm) is used.
4. Fusion of eggs and sperm in the test tube
The prepared sperm from the man are then brought together with the woman’s eggs in a test tube, where they swim in a special nutrient solution. The sperm must then fertilise the eggs independently and without any further assistance. The day after the follicular aspiration, the eggs are checked to see if they have been fertilised. The fertilised eggs develop into embryos, which are then stored in an incubator for two to five days.
5. Embryo transfer
On the day of the embryo transfer, the doctor, in consultation with the patient, inserts the embryos in the uterine cavity in accordance with the applicable statutory provisions. This is done with a soft plastic catheter. The transfer of the embryos is painless and takes only a few minutes. The embryos can then implant in the lining of the uterus where they can continue to develop.
To determine whether the procedure was actually successful or not, the woman takes a pregnancy test about two weeks after the procedure.