1. Hormonal stimulation of the donor
First, the donor of the eggs is given hormone treatment. This causes more eggs to mature than in the natural cycle. The doctor then removes these from the ovaries with a hollow needle (follicular aspiration). This procedure is usually performed under brief anaesthesia. A few days after the surgery, the donor’s menstrual bleeding occurs as usual, and her normal, natural cycle starts again.
2. Fertilisation of eggs in the laboratory by IVF or ICSI
The removed donor eggs are then usually fertilised with the recipient’s partner’s sperm in the laboratory by in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI) and then transferred to the recipient’s uterus a few days later (embryo transfer). Both unfertilised and fertilised eggs can also be frozen to be transferred later (cryopreservation).
3. Hormonal preparation of the recipient and embryo transfer
The recipient of the eggs is usually given hormones – oestrogen and progesterone – prior to the embryo transfer. As a result, the lining of the uterus builds up and is optimally prepared for the implantation of the eggs.