Crete Fertility Center

Oocyte cryopreservation or vitrification (egg freezing) is a rapidly advancing, breakthrough technology in which a woman’s eggs (oocytes) are extracted, frozen and stored (oocyte bank). Later, when she is ready to become pregnant, the eggs can be thawed, fertilized, and transferred to the uterus as embryos.

Oocyte cryopreservation is aimed at three particular groups of women: those diagnosed with cancer who have not yet begun chemotherapy or radiotherapy; those undergoing treatment with assisted reproductive technologies who do not consider embryo freezing an option; and those who would like to preserve their future ability to have children, either because they do not yet have a partner, or for other personal or medical reasons.

Oocyte cryopreservation is an important option for individuals undergoing IVF who object, either for religious or ethical reasons, to the practice of freezing embryos. Having the option to fertilize only as many eggs as will be utilized in the IVF process and then freeze any remaining unfertilized eggs can be a positive solution. In this way, there are no excess embryos created, and there is no need of unused frozen embryos disposition, a practice which can create complex choices for certain individuals.

Egg freezing can also be beneficial for women who, for the purpose of education, career or other reasons, desire to postpone childbearing. Freezing eggs at an early age may ensure a chance for a future pregnancy.

Additionally, women with a family history of early menopause have an interest in fertility preservation. With egg freezing, they will have a frozen store of eggs, in the likelihood that their eggs are depleted at an early age.

Egg (or embryo) donation for IVF fertility treatments, is indicated for women who, for various reasons, do not produce eggs. In these cases, it has been proven that egg / embryo donation is a very effective procedure in a wide range of problems. The indications for egg donation or embryo donation include the following conditions:

• Gonad dysgenesia, carrying an inheritable genetic disorder such as muscular Dystrophy or haemophilia. Such diseases can be passed on to their children. Rather than risk giving birth to a child who might suffer greatly and die at an early age, some women choose to have a chance of a perfectly healthy child via egg donation.
• Surgical procedures to / removal or absence of ovaries (ovarian damage following surgery, radiation or chemotherapy)
• Women born without or with under-developed ovaries (e.g. Turner’s syndrome).
• Poor response to ovarian stimulation
• Failure of multiple attempts of assisted reproduction methods (IVF, ICSI)
• Early menopause. This, however, occurs much earlier to some women, even in their teens or early twenties, before they would even have contemplated starting a family. This condition is called premature ovarian failure or premature menopause.

• Patient aged above 45 (menopause). After the menopause a woman is no longer capable of conceiving because her ovaries stop producing eggs and sex hormones.

ICSI, or Intracytoplasmic sperm injection, is a micromanipulation technique developed to help achieve fertilization for couples with severe male factor infertility or couples who have had failure to fertilize in a previous in vitro fertilization attempt (IVF).

The procedure overcomes many of the barriers to fertilization and allows couples with little hope of achieving successful pregnancy to obtain fertilized embryos. The procedure was first used at UCSF in 1994 and the first successful birth, achieved with ICSI assistance, was in February 1995. UCSF was the first San Francisco Bay Area program to achieve a pregnancy and birth with this “miracle” procedure.

How ICSI Works

The technique involves very precise manoeuvres to pick up a single live sperm and inject it directly into the centre of a human egg. The procedure requires that the female partner undergo ovarian stimulation with fertility medications so that several mature eggs develop (IVF). These eggs are then aspirated through the vagina, using vaginal ultrasound, and incubated under precise conditions in the embryology laboratory.

The semen sample is prepared by centrifuging (spinning the sperm cells through a special medium). This solution separates live sperm from debris and most of the dead sperm. The micromanipulation specialist picks up the single live sperm in a glass needle and injects it directly into the egg.

Through the ICSI procedure, many couples with difficult male factor infertility problems have achieved pregnancy. Fertilization rates of 70-80% (of all eggs injected) are currently being achieved, and pregnancy rates are comparable to those seen with IVF in couples with no male factor infertility.

Pregnancy rates in our unit are 48 – 50%, depending on the woman’s age.

Intra-Uterine Insemination (also known as artificial insemination) is the process of preparing and delivering sperm, so that, a highly concentrated amount of active motile sperm is placed directly through the cervix into the uterus.

IUI can be performed with or without fertility drugs for the female patient. Compared to timed intercourse, it is generally accepted that there is a 2-fold higher pregnancy rate with IUI. Thus, for infertility patients, IUI is commonly performed as a low-tech, cost-effective approach to enhancing fertility in patients. Prior to initiating IUI treatment, women must have at least one documented open fallopian tube as demonstrated by hystero – salpingogram (the tubal dye study).

There are several techniques available for preparing the sperm for IUI. All of the techniques involve separating sperm from seminal fluid. It is not possible to inject semen directly into the uterus because of chemicals in the fluid that can cause extremely painful uterine contractions.
Motile sperm are separated from dead sperm and other cells through the use of viscous solution. We will ask that the male partner bring or produce his specimen for our laboratory several hours prior to the IUI procedure.

There are two different methods of ovarian stimulation (ovulation induction). The first is used for women who are not ovulating spontaneously (irregular or infrequent menstruation). In such cases, the aim is to stimulate the release of one egg a month. This is most easily done by prescribing fertility pills. If this medication is not effective, then injections of a small dose of gonadotropins may be necessary.

In the second situation, the woman is ovulating spontaneously but has unexplained infertility or her partner has mild male-factor infertility. In such a case, the aim of ovulation induction is to stimulate the production of 2 to 4 large follicles, so that several eggs will be released. This is most easily achieved by injections of gonadotropins. This treatment is combined with intra uterine insemination (IUI) to bring the sperm closer to the egg.

Sperm from two sources can be frozen: from ejaculates or from fluid extracted in the operating room during surgical procedures (vasal, epididymal and testicular sperm specimens). The sperm cryopreservation is usually frozen for a period of one year (sperm bank); at that time, future arrangements are discussed. It is generally believed that sperm that have been through the freeze-thaw process are no more likely to result in birth defects than freshly ejaculated sperm.

Crete Fertility Centre is in co-operation with the largest sperm bank in Europe, Cryos Bank in Denmark, in order to secure the highest sperm quality standards in case of assisted reproduction with the use of donor’s sperm.

All Donors are under a state of the strictest and obligatory procedures every three months, in order to secure sperm quality. These procedures include psychological examinations, full pathological, haematological and microbiological tests in order to trace genetic abnormalities, sexually transmitted diseases and various viruses (such as hepatitis). All sperm samples become approved after being quarantined for 6 months.

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