Services offered include:
Women may choose to have donated oocytes if they have hypergonadotrophic hypogonadism, have diminished ovarian response, have persistently poor oocyte and/or embryo quality in previous ART's, or have known hereditary/genetic defect that can be carried over to the offspring.
In Vitro Fertilization (IVF)
In-vitro fertilization (IVF) is the process whereby the female partner's ovaries are stimulated to produce eggs. These are then removed and placed together with her partner's sperm in a petri dish and allowed to fertilize. The resulting embryos are then transferred into her uterus after 2-3 days. IVF is used in cases of tubal blockage, male factor infertility or previously failed IUI cycles.
The ovaries will be stimulated to produce eggs. Firstly, a gonadotropin-releasing hormone (GnRH) analogue is given for about 8-10 days. Secondly, daily injections of human menopausal gonadotrophin (hMG) are given to stimulate the ovaries to produce an increased number of follicles containing the eggs. After about 8 days, the number and size of the follicles will be measured using ultrasound. When 1-2 of the follicles reach 18mm in diameter, an injection of human chorionic gonadotrophin is given, and the oocyte retrieval scheduled for 36hrs later.
The oocytes will be retrieved via transvaginal ultrasound. Ultrasound allows the physician to visualize the follicles and can then push a needle into each of them and aspirate the fluid inside the follicle containing the oocyte. The follicular fluid is examined by laboratory personnel for the presence of the egg and if found, is placed in an incubator. This is done for all the follicles. At the time of oocyte retrieval or immediately thereafter, the male partner's perm will be processed to isolate the highest quality sperm. Approximately 5hrs after the oocyte retrieval, the oocytes and sperm are put together in a petri dish and placed in an incubator.
The next day, the oocytes are observed to see whether normal fertilization has occurred. The fertilized oocytes are then left in the incubator to develop into embryos. After 2-3days after oocyte retrieval, the embryos are transferred into the uterus of the woman using a special catheter. Hormonal treatments are given for the following 3 weeks, after which a pregnancy test is scheduled. Any excess embryos not transferred may be cryopreserved for later use (see Embryo Cryopreservation and Thawing)
The normal success rate with this procedure is about 25-30% depending on the age of the patient.
IntraCytoplasmic Sperm Injection (ICSI)
Intracytoplasmic Sperm Injection (ICSI) is the process whereby a single sperm is injected directly into the cytoplasm of the egg. ICSI is the method of choice for patients with severe male factor infertility, and for patients who have had previously failed or poor fertilization resulting from conventional IVF.
The eggs are retrieved from the woman's ovaries in the same way as for IVF. The eggs are then stripped of all surrounding cells and placed in a droplet and the male partner's sperm placed in another droplet. The sperm can be obtained via ejaculation or in severe cases, directly from the testis or epididymis using microsurgical sperm retrieval techniques.
The oocyte is held in place by a specialized holding micropipette. With a microinjection pipette, one sperm is picked up (aspirated) and then carefully injected into the cytoplasm of the oocyte. This is done for all the eggs. The eggs are then placed in the incubator, and checked the next morning for fertilization.
The fertilized eggs are then allowed to develop for another 24-48hr, after which they are transferred into the uterus via a thin catheter. Hormonal treatment to help maintain a pregnancy is given for the next 2 weeks.
The success rate for ICSI is usually around 30-35%.
Sperm Cryopreservation and Thawing
Sperm can be cryopreserved in cases where the male might have difficulty in producing a specimen at a given time. If sperm were retrieved microsurgically, excess sperm may be stored to avoid having to repeat the invasive surgical procedure. Also, for patients planning to undergo chemotherapy or radiotherapy (for cancer), sperm may be cryopreserved as the therapy may diminish their sperm production. Sperm can also be frozen for persons wishing to donate their sperm to infertile couples.
Sperm retrieved by masturbation, testicular biopsy or microsurgical epididymal sperm aspiration are placed together with a cryoprotectant and stored in cryostraws in liquid nitrogen at a temperature of -196°C. This can be thawed at any time, and the cryoprotectant can be removed and the sperm used for ART procedures.
Embryo Cryopreservation and Thawing
When excess embryos are present after an embryo transfer, these can be frozen and then transferred in subsequent cycles, if the patient does not become pregnant. This would save her from undergoing another oocyte retrieval procedure. She may also elect to have her embryos donated to another infertile couple.
Excess embryos are placed with a cryoprotectant and aspirated into cryostraws, and then gradually frozen to a temperature of -196°C, and placed in liquid nitrogen. Storage can be indefinite but requires written approval/consent from the parents every 3 years.
When the patient wants to transfer embryos that are in cryostorage, these can be thawed prior to or on the day of transfer, assessed for survival and development, and then transferred.
Frozen Embryo Transfer (FET)
Frozen embryo transfer (FET) involves the following:
- Thawing of cryopreserved embryos.
- Assessing the survival and development of the embryos.
- Transfer of the embryos into the uterus of the recipient.
Assisted hatching is the opening of the zona pellucida , surrounding the embryo, to help the embryo/blastocyst "hatch" or emerge from the zona and implant in the uterus. Assisted hatching is usually indicated in older women, and those with failed implantation in previous cycles.
Prior to embryo transfer, a small opening is made in the zona pellucida using microdissection tools. The embryos are then transferred normally.
The process of gender selection increases the chance of having a female or male child, by separating sperm that bear the X chromosome (female) and those that have the Y chromosome (male), and inseminating with whichever sample is desired. The procedure can be employed for couples who want a child of a specific gender.
The procedure used is the sedimentation method. This method is used similarly for both male and female selection and takes approximately 2-2½ hours to process. On average, it takes about 3-4 cycles to achieve a pregnancy with this method.
Our success rate is approximately 80% for male selection and 72% for female selection.
A traditional surrogate is one who donates her oocytes and carries the pregnancy using sperm from the intended natural father (husband) or a donor.
The surrogate's ovaries are stimulated hormonally to produce follicles containing the eggs. An ultrasound scan is performed to determine the number and size of the follicles and also the thickness of the endometrium, lining the uterus, to see whether it is ready for implantation. Also, blood hormone levels will be measured. Ovulation will be induced by an injection of human chorionic gonadotrophin (hCG), and the egg will be released 36-48hr later. The semen from the intended natural father is processed to select the highest quality sperm. The physician will then inject this sperm via a catheter through the vagina and cervix, into the uterus. If conception occur, the surrogate will carry the pregnancy to term.
The gestational surrogate is one who only carries the pregnancy to term, and the eggs are derived from another source.
This procedure is very similar to IVF, except that instead of transferring the embryos into the female patient, they are transferred into the uterus of the designated surrogate.