Egg donation: fresh or vitrified eggs – what the difference really is

During the first consultation regarding egg donation, one question often comes up without patients realising they will have to answer it: ‘fresh’ donation or ‘frozen’ eggs? Some clinics offer both, others just one of the two. Here’s what sets them apart.

Two approaches

• Fresh donation. The donor undergoes ovarian stimulation whilst your endometrium is prepared using hormones. On the day of her egg retrieval, the eggs are fertilised with your partner’s or a donor’s sperm, and an embryo is transferred to you a few days later, or the embryos are frozen. Your two cycles must therefore be synchronised.
• Vitrified eggs. The eggs have been retrieved and vitrified in advance. They are thawed and fertilised when your endometrium is ready, without waiting for a donor’s cycle.

In both cases, the Greek regulations regarding donors are the same: an egg donor must be under 35 years of age, unless an exception is authorised by the National Authority for Assisted Reproduction; she must undergo medical, genetic and psychological assessments as determined by that Authority; and gametes from more than one donor may not be used during the same cycle. Following a decision by the Authority in July 2025, a donor may not undergo stimulation more than six times in total, and there must be a minimum of four months between two egg retrievals. The general framework is set out in the article on Greek donation law.

Tests required of donors in Greece

Whether the donation involves fresh eggs or vitrified eggs, the list of tests is set out in a 2023 decision by the National Authority for Assisted Reproductive Technology. It includes, in particular:

• serological tests for HIV, hepatitis B and C, and syphilis;
• screening for carrier status of thalassaemia and sickle cell anaemia, cystic fibrosis, spinal muscular atrophy and a common form of hereditary deafness (GJB2 gene), as well as a karyotype;
• for egg donors, in addition: Fragile X syndrome, blood group and Rhesus factor, a gynaecological examination and vaginal swabs;
• an assessment by a psychologist.

For a donor from another country, genetic counselling is provided for conditions that are commonly carried within her population of origin.

What the studies show

The best evidence comes from a Spanish randomised trial published in 2010, which allocated 600 recipients to either fresh or vitrified eggs. The ongoing pregnancy rate was 43.7 per cent with vitrified eggs and 41.7 per cent with fresh eggs: no difference, in a laboratory with extensive experience in vitrification.

Large registries often show slightly less favourable results for vitrified eggs. In the United States, an analysis of over 30,000 donor cycles reported between 2013 and 2015 found a live birth rate per cycle started of 51.1 per cent with fresh eggs, compared with 39.7 per cent with vitrified eggs. In Europe, the ESHRE register for 2020 reports a pregnancy rate per transfer of 51.3 per cent with fresh donor eggs and 45.7 per cent with thawed eggs. However, the difference is not consistent: for 2022, the American SART registry reports a birth rate per recipient cycle of 39.2 per cent with fresh eggs and 38.9 per cent with vitrified eggs.

How can these figures be reconciled? The registries include laboratories of very different standards, and the number of eggs allocated is not always the same across the two approaches. In 2021, the American Society for Reproductive Medicine (ASRM) concluded that there was moderate-quality evidence supporting equivalent pregnancy rates per transfer, but insufficient evidence to compare birth rates. In other words: the technique itself is not at fault, but the laboratory’s experience and the number of eggs do matter.

The advantages of each option

For a patient who is travelling, the predictability of vitrified eggs is a real advantage: flights and accommodation can be booked with greater peace of mind. Fresh donation, on the other hand, does not depend on the eggs’ survival during thawing. If the partner is unable to attend on an uncertain date, see pre-freezing of sperm.

Questions to ask the clinic

• Do you offer fresh eggs, vitrified eggs, or both?
• What is the minimum number of eggs I will be allocated, and what is the plan if this number is not reached?
• Are eggs from the same donor shared amongst several recipients?
• For vitrified eggs, what is your laboratory’s survival rate following thawing?
• What happens to embryos that are not transferred?

The success rates to expect, and how to interpret them, are detailed in the article on donation success rates; the cost in the price of IVF in Greece. If you would like us to compare the proposals from two clinics together, please write to me.

Frequently asked questions

Source: https://fertilitegrece.com/en/blog/fresh-vs-frozen-donor-eggs/ — Triada Baloukoudis, IVF patient coordination in Greece. General information, not medical or legal advice. Printed on

Triada Baloukoudis
Independent IVF patient coordinator in Thessaloniki, with 24 years of experience supporting patients travelling from abroad. More · Contact · Facebook