Embryo Freezing

Why should I consider freezing my embryos?

You might have leftover embryos after your previous in vitro fertilization (IVF) cycle and you will have the option of using these embryos in the future rather than having to go through another ovarian stimulation cycle and egg collection.

While you are undergoing IVF treatment, we might need to cancel the process following the egg collection if the conditions are not suitable for transfer (for example if your endometrium is not well developed, or if you over respond to the fertility drugs developing a condition known as ovarian hyperstimulation syndrome, or if you are found to have fluid in the Fallopian tube or inside the uterus).

You are planning to have genetic testing of the blastocyst(s).

Embryos can also be frozen to preserve fertility so it may be possible to have a baby at a later date.

When are the embryos frozen?

Not all embryos are suitable for freezing so only good quality embryos will be chosen to freeze since they will have the very best chances of surviving the thaw and implanting successfully.

Embryos can be frozen at different stages:

What is the process for freezing embryos?

The embryos are put in a special solution containing substances (cryoprotectants), which help to draw water out from the embryo and provide protection in the cells from damages caused by ice crystals forming while they are frozen.

There are 2 methods of cryopreservation process used in IVF labs: either slow freezing or fast freezing (vitrification). Vitrification is often used as in the process of freezing rapidly, the water molecules don’t have time to form ice crystals, and instead instantaneously solidify into a glass-like structure.

Once frozen, the embryos are then stored in tanks of liquid nitrogen until you’re ready to use them.

Does freezing/thawing damage the embryos?

Although most embryos do survive the freeze thaw process, some may not survive. It is also not uncommon for those embryos that do survive to lose one or two cells or develop fragments. In many cases however the embryo will recover and continue to develop. The embryologist or the consultant will talk to you about whether the embryo is suitable to be transferred. Approximately 80-85% of cleavage stage frozen embryos, and 95% of blastocyst survive the process of thawing.

How long can my embryos be stored for?

Embryos are not affected by the length of time they’re frozen for. The allowed standard storage period for embryos might be different based on the country you have treatment. Your fertility team will be able to advise you.

Book a consultation

NOW-fertility’s commitment is to make fertility care accessible, successful and stress free for patients.

If you are ready to start your journey, book a consultation with one of our experienced fertility consultants.

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Global Clinical Network

NOW-fertility will coordinate the whole treatment cycle and will only associate with the best providers worldwide, made up of licensed Centres of Excellence (with above national average fertility success rates) for assisted conception treatment and outstanding Satellite Clinics for diagnostic and monitoring investigations.  This infrastructure will make the fertility journey considerable quicker, whilst being more tailored, accessible and affordable for patients.

Unicorn NOW Platform

This bespoke and highly secure cloud-based platform is positioned to change the way the millions of people annually who want a baby experience fertility treatment.  We integrate Machine Learning data to prognosticate the best chances of success and use Artificial Intelligence to drive patient engagement.

Reduced timescales

One of the key problems with the current IVF service which NOW-fertility can resolve is the speed we can provide both advice, support and treatment.

Our research indicates we will be able to reduce the time commitment of a patient during the highly stressful period from initial contact to egg collection from 24-30 hours down to 8 hours.


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