Oocyte vitrification

Preserve your fertility with Oocyte vitrification

What is oocyte vitrification?

Today, mainly for social reasons, women are delaying their time to become mothers, reducing the possibility of conceiving naturally. The quality and quantity of the oocytes drops considerably after 35 years of age, reducing the probability of achieving a pregnancy.

Thanks to advances in assisted reproduction, today women can plan the time to become mothers thanks to vitrification, which allows them to freeze their oocytes for years. When a woman decides to become a mother they are thawed, and these oocytes preserve the quality they had when they were frozen.

The simple vitrifying procedure allows women to preserve their fertility. It consists in hormone stimulation and ovarian puncture to extract the eggs.

Subsequently, in the laboratory they are stored at -196°C until the decision is taken to use them. At present, oocytes can be frozen safely, with a survival rate of about 80-95%.

When is it recommended?

For medical reasons

  • Women diagnosed with cancer who have still not started chemotherapy and/or radiotherapy.

For personal/social reasons

  • Women who want to preserve their capacity to have children, either because they don’t have a partner still, or for medical or personal reasons.
  • Women who are undergoing in vitro fertilisation and do not wish to freeze extra embryos for ethical / religious reasons.

Phases of oocyte vitrification

  1. Hormonal stimulation is done by using drugs whose action is similar to that of hormones that women produce called gonadotropins. The purpose of this treatment is to obtain the development of one or more follicles. An egg will then mature inside this follicle. At present, the most commonly employed drug formats are injections that are applied subcutaneously, offering patients both independence and comfort. The dose of gonadotropin and its start date may vary depending on the case. The ovarian stimulation process is regularly monitored through vaginal ultrasounds that report on the number and size of developing follicles. At time these data are complemented by hormonal determinations.

  2. Follicular puncture is a simple surgical procedure that is performed on an outpatient basis using local anaesthesia or short-duration general anaesthesia (intravenous sedation), after which the patient will remain under observation for a variable period of time, which tends to range from 2 to 4 hours. The follicles are located by ultrasound, they are punctured and their contents are aspirated and sent to the laboratory. Embryologists will then identify the oocytes and safeguard them in an incubator for 2-3 hours, at which time they will be vitrified.

  3. Mature oocytes are identified in the laboratory and vitrified. This technique consists of replacing the water with a cryoprotective medium and the subsequent high-speed drop in temperature to -196º C, thus preventing the formation of crystals inside the oocyte that could damage the cellular structures. From a biological viewpoint, the oocytes can remain in storage at these low temperatures for the time that is necessary, until the patient wishes to use them.

Results in
vitrification of oocytes

At present, thanks to the good results obtained with vitrification, the oocytes can be frozen with full security and assurance, obtaining excellent results are thawing them, with a survival rate around 90%. The unfrozen oocytes keep the same fecundation rates as fresh eggs, and the resulting embryos also have the same potential for development.

90.0%

Vitrification oocyte