Freeze-all is now the norm, and it changes how you plan a treatment trip

If your mental picture of IVF is a single continuous process — stimulation, egg retrieval, embryo transfer, pregnancy test, all in one stretch — it is out of date. And if you are planning to travel for treatment, that outdated picture will lead you to book the wrong trip.

What the European registry shows

The European IVF Monitoring Consortium reported preliminary 2023 data at ESHRE in July: 1,156,316 treatment cycles across 1,473 centres in 36 countries, resulting in 247,021 children.

The striking part is the breakdown. Frozen embryo transfer is now the single largest category, with 401,483 cycles, against 158,649 conventional fresh IVF cycles. Frozen transfers account for roughly 43% of all activity, with a delivery rate of 27.6%.

In other words, the default modern pathway is no longer “retrieve eggs, transfer an embryo three to five days later.” It is increasingly: retrieve eggs, fertilise, grow embryos to blastocyst, freeze everything, and transfer in a later cycle.

A caveat: this is preliminary registry data presented at a conference, and reporting completeness varies between countries. It describes European practice, so it is indirect evidence about clinics elsewhere — though the freeze-all shift is a global trend.

Why clinics do this

There are real clinical reasons, not just logistics.

The hormonal stimulation that produces multiple eggs also changes the uterine lining, and for some patients that makes the lining less receptive in the same cycle. Separating retrieval from transfer lets the body return to a more natural hormonal state first. It also removes the time pressure: embryos can be observed to day five or six, genetic testing can be done if indicated, and the transfer can be scheduled when conditions are right rather than when the calendar forces it.

It is also what makes single embryo transfer practical, which the Australian data discussed in our piece on success rates showed can reach 68.2% cumulative live birth over three cycles with a multiple birth rate of just 2.9%. If you have several frozen embryos banked, transferring one at a time costs you nothing in cumulative terms and avoids the risks of twins.

What this means for your travel plan

This is where it becomes practical for anyone considering treatment abroad.

Expect two trips, not one. The first covers monitoring and egg retrieval — typically around ten days to two weeks, depending on how your body responds to stimulation. The second covers the transfer, which is a much shorter visit, often just a few days. They are usually separated by at least one menstrual cycle.

This is usually good news for cost. A frozen transfer is considerably cheaper than a full fresh cycle, and repeat attempts happen at that lower price. It also means you are not paying for a long second stay.

Ask how monitoring works between trips. Much of the preparation for a frozen transfer — bloodwork, ultrasound to check the lining — can often be done with a clinic near home, with results sent to your treating clinic. A clinic used to international patients will have a protocol for this. If they do not, that tells you something about how much experience they actually have with travellers.

Ask about the laboratory’s freezing method and storage. Vitrification is the current standard. Reasonable questions: what survival rate do their frozen embryos have on thawing, how long is storage included in the price, what does it cost afterwards, and what happens to your embryos if you decide to move them or stop treatment.

Ask what happens if the cycle is cancelled. Not every stimulation produces usable embryos. Find out in advance what portion of the cost is refundable or credited, because this is the scenario people forget to ask about and it is not rare.

One question worth asking directly

For donor-egg recipients, there is good evidence that how the lining is prepared for a frozen transfer matters. A study of more than 67,000 transfers found natural-cycle preparation outperformed hormone replacement on live birth and on obstetric outcomes. It is a specific, informed question to put to any clinic: do you offer natural-cycle frozen transfer, and is it appropriate for me?

The freeze-all shift has made IVF safer and more flexible. It has also quietly made it a two-trip proposition, and knowing that before you book flights is worth a great deal.

To see how the full sequence fits together, read the patient journey.