Fri, 08 Dec 2023

Donor Eggs Fresh or Frozen?

16 Nov 2022, 04:17 GMT+10

Fresh donor eggs were previously the only option. The fertility clinic synchronizes the cycles of the egg donor and recipient using pharmaceuticals. After two weeks of stimulation with fertility medicines for the donor, the eggs are then removed and fertilized in the embryology lab. The recipient receives one of the generated embryos and gets preserved for use later.

Unfertilized eggs may now be effectively frozen hence advances in cryopreservation (freezing) technologies. The eggs freezing is quick during assisted reproductive technology called vitrification, which makes them less likely to be injured than in earlier techniques.

Improved cryopreservation (egg freezing) methods allowed to freeze of donor eggs efficiently and safely. Guidelines were published in 2013 by the American Society for Reproductive Medicine, stating that oocyte vitrification and warming should no longer be considered experimental. Due to the success of frozen eggs, egg banks became available, allowing individuals a wider variety of options when considering the best donor.

The Initial Steps In The Egg Donation Process

Three things can happen when an infertility specialist extracts eggs from a donor:

Unfertilized fresh eggs can be saved for later use. They are referred to as frozen donor eggs.

The fresh eggs may be fertilized to produce an embryo, which is transplanted into the patient's uterus after several days of development. This procedure is known as a fresh embryo transfer.

The fresh eggs are fertilized to produce an embryo that will be frozen in preparation for a future transfer. It is called a frozen embryo transfer.

The initial steps in the egg donation process are the same for fresh and frozen eggs. All donors are screened to ensure total physical and psychological health and have proven fertility. Then the donor is stimulated with fertility medication for two weeks, and after the day of egg collection, can go ahead when the eggs have matured. In a fresh egg donor cycle, the collected eggs are fertilized with sperm (from the father or a sperm donor) right after.

In several days, the embryos will be transferred to the intended mother or surrogate or frozen for future use. During a frozen egg donor cycle, eggs are retrieved from the donor and vitrified (frozen) before fertilization. They are afterward thawed and fertilized. Once embryos are created, they are ready to be transferred to the recipient.

So, What Is Better − Fresh vs. Frozen Eggs? This question can be answered by Birol Aydin Scientific director at Ovogene - is the first AI-driven egg donor bank in the world

Choosing between fresh or frozen eggs may seem a monumental task for intended parents. It is fair since we are conscious that you want to take every precaution to increase your chances of having children! However, both treatment options have advantages and disadvantages, and it comes down to being a personal decision on the best treatment for you. There are various factors to consider when deciding whether to use fresh or frozen donor eggs.

In IVF fresh donor cycle give opportunities to get fresh egg after egg retrieval and make fertilisation directly with any quality of donor eggs. The most of IVF laboratory and embryologist find this way much easier and safety while there is no additional warming process and all process they can manage during daily routine of laboratory activity. Mostly embryologists are considering fresh donor has better structure during sperm injection process (ICSI) . The another point organization part during fertilization process. Fresh oocyte has more flexibility for embryologist for fertilization timing and there is no additional process for warming.

But what about the quality and efficiency points of fresh donor eggs? Is there a big efficiency difference between a fresh egg and a donor egg?

We can find answer to these questions if we have a big efficiency data and routine fresh and frozen donor egg cases. Normally we have done egg pick up 35 hours or 36 hours post trigger. Natural concept of fertilisation process done till 40 hours. Our aim to complete all fertilisation process in this timing rage. When we have fresh donor egg pick up after 35 or 36 hours post trigger we just remove cumulus complex cells after 2 hours and we make fertilisation by ICSI after 1 hour. Practically we stay in range of 40 hours. Most of the embryologists and IVF Laboratory just fertilise all eggs as fresh without quality range. May be number of oocytes are the high but finally cumulative efficiency is the same as frozen oocyte after the final stage of blastocysts check.

Frozen donor eggs are much protective and under control while selection of the oocytes and all micromanipulation require more attention. That's why morphological standards are more strict then fresh donor eggs. Finally with less number of frozen egg we are getting same number of blastocysts as we have done fresh donor eggs. Final cumulative outcome is the same. Depends of freezing startegy of egg banks this efficiency range can be increase.

As Ovogene we are using AI based morphological selection for oocytes. That means we avoid all morphological risks by machine learning. Also we are able to detect spindle visuilation. The most of the meiotic error happening because of spindle activity. Specially main problem of cleavage arrest mostly happening because of spindle visuilation or morphological damage of meiotic spindle. Another important issue we can receive also medical information from egg donor and previous efficiency through AI platform and AI based software can decide which donor egg can go for freezing and may give better result.

Imoproved vitrification protocols and also advanced technologies as AI are increasing chance of better outcome for egg banking. Frozen egg always give more option for embryologists and IVF laboratories. Day of fertilisation we may nor receive sperm sample, we may have problem on technical equipment or external problems may happen. These problems may create difficulties for fresh donor egg fertilisation. But frozen donor eggs always give us more option and comfortable work plan for fertilisation and embryo creation. Also patients may have more flexible regardin donor profile selection and avoid long waiting time of fresh donor preparation. Finally even with good selected egg donor may give dissapointed number of eggs or quality of eggs on day of egg pick up.

According many scientific publication there is no significant difference between frozen and fresh donor eggs as final cumulative blastocysts or pregnancy outcome. But new trand of advance technologies are joining in egg banking and results are increasing for frozen donor egg efficiency and outcome.

Sign up for Sweden News

a daily newsletter full of things to discuss over drinks.and the great thing is that it's on the house!