Cryopreservation

Freezing of reproductive cells: oocytes / sperm

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Freezing reproductive cells allows the preservation of fertility for varying periods of time, both for social purposes, but especially in the case of diseases or medical treatments that can irreversibly affect fertility.

The Gynera Clinic offers the latest and most effective methods for cryopreservation of oocytes, sperm or embryos in its own accredited and functional Reproductive Cell Bank since 2007.

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Freezing oocytes

Freezing oocytes is a procedure that allows their preservation in the short or long term.

It can be used for cryopreservation of one’s own reproductive cells or for donated oocytes.

The vitrification technique, developed in recent years, allows an increasingly better survival rate on thawing, especially in the hands of experienced specialists.

Frozen oocytes are stored in small devices called sequins, stored in liquid nitrogen, at temperatures of -1960 C. The oocyte bank is constantly monitored and supplied with liquid nitrogen to ensure optimal storage conditions.

How is oocyte freezing performed?

In order to increase the chance of success of the future reproductive procedure, more frozen oocytes are needed, the higher the number, the older the woman is.

To obtain more oocytes, ovarian stimulation medication is administered for 9-10 days, similar to the IVF procedure. After the development of several follicles containing oocytes, the oocytes are taken by ovarian puncture, with sedation or anesthesia.

Oocytes are processed, frozen and stored in the Oocyte Bank.

Freezing involves sensitive stages: dehydration of oocytes and impregnation with cryoprotective media.

Upon thawing, they will be fertilized in the laboratory by IVF / ICSI technique, in order to obtain embryos.

Chances of success and risks
  • Only mature oocytes, which have certain characteristics in the laboratory, can be frozen
  • At least 80% of frozen oocytes are resistant to freezing, but the percentage depends on age and associated conditions
  • The chances of IVF success are similar to IVF procedures in which oocytes are not frozen
  • The risks of pregnancy complications are similar to natural pregnancies
  • From existing data, cryopreservation does not appear to increase the risk of fetal abnormalities
Why freeze semen?
  • If you want to postpone starting a family or just take precautions
  • If you have long departures from the locality and your partner is going to resort to assisted reproduction in the meantime
  • If you are going to have a vasectomy, but consider that you might change your mind later
  • If you have a genetic or fertility problem at risk in your family
  • If you have large fluctuations in the parameters of the spermogram
  • If you are going to have surgery that may affect your fertility
  • If you are going to have chemotherapy, radiation therapy or other treatments that affect fertility
Freezing of embryos

  • Freezing embryos allows the preservation of fertility when the woman or man who wants to preserve her fertility already has a stable partner with whom she wants to start a family. More details about embryos freezing here …

Why freeze oocytes?
  • If you want to postpone pregnancy beyond the age of 30
  • If you do not have a stable partner and you are over 30 years old
  • If you are going to have surgery that may affect the ovaries
  • If you are going to have chemotherapy, radiation therapy or other treatments that affect fertility
What is the optimal number of frozen oocytes to have a chance of success in IVF?
  • Optimal period of freezing of oocytes: before 30 years
  • Optimal number of frozen oocytes: 14-15, if the age is under 35 years
  • After 35 years, oocyte quality is declining and more than 30 oocytes may be needed to achieve a 50% chance of success in the IVF procedure.

To obtain a euploid embryo (with normal number of chromosomes) in IVF, it is necessary:

6 oocytes under 35 years

11 oocytes 38 – 40 years old

18 oocytes 42 – 43 years old

Implantation rate of an embryo transferred to the uterus:

under 35 years – 35% of embryos are implanted

37-38 years – 20% of embryos are implanted

39-40 years – 10% of embryos are implanted

44 years – 2% of embryos are implanted

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Freezing sperm

Freezing sperm is a procedure that allows sperm to be stored for a variable period of time.

It can be used for cryopreservation of one’s own semen or for donated semen.

Frozen semen is stored in cryotubes or sequins, stored in liquid nitrogen, at temperatures of -1960 C. The sperm bank is constantly monitored and fed with liquid nitrogen, to ensure optimal storage conditions.

How is sperm frozen?

Sperm is harvested by masturbation, as for the spermogram.

In special cases, it can be harvested surgically, by puncture / testicular biopsy

The specialist performs the freezing in special conditions, the technique being very efficient.

At freezing, in the case of semen with normal parameters, several cryotubes can be obtained, which allows subsequent use for several reproductive procedures.

Chances of success and risks
  • Most frozen sperm are resistant to freezing
  • The chances of IVF success are similar to IVF procedures in which semen is not frozen
  • The risks of pregnancy complications are similar to natural pregnancies
  • From existing data, cryopreservation does not appear to increase the risk of fetal abnormalities