Having selected your donor, there is about a 6-8 week wait. During that time, the donor is stimulated with medication to prepare her for egg retrieval.
Eggs are retrieved from a donor by means of vaginal ultrasound guided aspiration of ovarian follicles. All of the retrieved eggs are inseminated with the sperm brought from Ireland by a member of the Sims IVF medical staff. If fertilisation takes place, the eggs (zygotes) are cryopreserved. You will then receive a call from a co-ordinator to inform you how many zygotes have been frozen.
The zygotes are brought to Sims IVF in Dublin to be thawed and grown for between 4 and 5 days after which the embryo(s) are either placed into the uterus of the female recipient or they are cryopreserved for your future use, or both.
After fertilisation, you are informed of arrangements for embryo transfer. Once the fertilised embryos are confirmed, preparation of the female recipient begins. This is organised by your co-ordinator. A month long treatment schedule is set up and a prescription for special medication is given to the woman to help prepare her womb.
We want to ensure that the embryos are placed in the womb at the optimal time for implantation. This is achieved initially by starting on the contraceptive pill for a short period. Then a nasal spray is used to make the ovaries inactive. This is known as down regulation. Some women requiring donor eggs do not menstruate and therefore may not need the spray. Once down regulation has been achieved, hormone tablets are taken daily to prepare the lining of the womb to receive the embryos.
Ultrasound scans are carried out following commencement of the hormone tablets so that the doctor can assess your womb lining to ensure that it is the right thickness for embryo transfer. If the womb lining is satisfactory, an additional hormone – Progesterone – is taken as advised. This ensures that the lining of your womb is in the best possible condition for implantation of the embryos.
The fertilised eggs or embryos are grown in the laboratory for 4 to 5 days until ready for transfer into the uterus. They are replaced through the neck of the womb using a small plastic tube. This is usually a painless procedure rather like having a cervical smear test and it takes 5-10 minutes to perform.
Following embryo transfer, the hormone tablets and Progesterone medication are continued daily as indicated in your treatment schedule. These hormones reflect the changes that normally occur in a woman’s body at this time. While the hormone supplements are being given, a period will not usually occur, but this does not necessarily mean pregnancy has begun. Two weeks after the embryo transfer, a blood test is carried out to establish whether you are pregnant. If this is positive, a scan is performed three weeks later to ensure that the pregnancy is inside the womb and that a fetal heartbeat can be seen. Hormone supplements continue until at least week 12 of pregnancy.
If your pregnancy test is negative, the hormone dose is suspended and a period usually starts within 2-3 days. A review appointment is scheduled with your consultant if this treatment is unsuccessful.