Once your embryos have been created in the lab, one important decision remains: should they be transferred straight away in a fresh cycle, or frozen and transferred later in a frozen embryo transfer (FET)? It is one of the most common questions couples ask during IVF treatment — and the honest answer is that neither option is automatically “better.” What matters is which one is better for you.

In this guide, the fertility specialists at Myra IVF Centre in Kenya, led by Dr. Sarita Sukhija, explain how fresh and frozen transfers actually compare on success rates, safety and cost — and how we decide which one gives you the best chance of a healthy pregnancy.

First, What Do “Fresh” and “Frozen” Actually Mean?

Both fresh and frozen transfers use embryos created in the same way — eggs are collected during egg retrieval, fertilised with sperm (through conventional IVF or ICSI), and grown in the lab, often to the blastocyst stage. The difference is purely one of timing.

• Fresh embryo transfer: The embryo is placed into the uterus 3–5 days after egg retrieval, in the same stimulated cycle.
• Frozen embryo transfer (FET): The embryos are cryopreserved (frozen) and transferred in a later, separately prepared cycle — weeks or even months afterwards.

How Modern Embryo Freezing Works (Vitrification)

Concern about “damaging” embryos by freezing them is understandable, but largely outdated. Today’s clinics use vitrification — an ultra-rapid freezing technique that turns the embryo and its surrounding fluid into a glass-like state without forming the ice crystals that used to cause damage with older slow-freezing methods.

The results speak for themselves: in a good embryo freezing laboratory, more than 95% of vitrified embryos survive thawing, and a thawed embryo that survives is considered just as capable of implanting as a fresh one. This single advance is the reason frozen transfers have become so successful — and so common — worldwide.

The Real Question: Which Has Better Success Rates?

Here is where it gets interesting. In a fresh cycle, the same high doses of hormones used to grow multiple eggs can also make the uterine lining (endometrium) less receptive at the exact moment of transfer. In some women, progesterone also rises too early, pushing the lining “out of sync” with the embryo.

A frozen transfer sidesteps this. Because the transfer happens in a later cycle, the body has recovered from stimulation and the lining can be prepared in a calmer, more natural hormonal environment. Better embryo–endometrium synchrony is the main reason FET can improve implantation in certain patients.

But — and this is important — frozen is not a magic upgrade for everyone. Large studies show that for women who respond normally to stimulation, fresh and frozen transfers produce very similar live birth rates. The clear advantage of FET shows up mainly in specific groups:

• High responders (for example, many women with PCOS) who produce a large number of eggs and have very high hormone levels.
• Women at risk of OHSS, where a “freeze-all” approach is safest.
• Cycles using genetic testing (PGT), where embryos must be frozen while results are awaited.
• Cases of premature progesterone rise or a lining that was not ideal on the planned fresh transfer day.

Fresh vs Frozen Embryo Transfer: Side-by-Side Comparison

Factor	Fresh Embryo Transfer	Frozen Embryo Transfer (FET)
Timing	3–5 days after egg retrieval, same cycle	A later, separately prepared cycle
Uterine environment	Still affected by high stimulation hormones	Recovered, more natural lining and better synchrony
Success rate	Excellent for normal responders with an ideal lining	Equal or higher for high responders, OHSS risk and PGT cycles
OHSS risk	Higher if many eggs are produced	Greatly reduced (freeze-all avoids it)
Genetic testing (PGT)	Not possible in the same cycle	Required — embryos frozen while results are awaited
Time to pregnancy	Shorter — transfer in the same cycle	Longer — a preparation cycle is needed first
Cost consideration	No added freezing/storage cost for that transfer	Adds freezing, storage and thaw-transfer costs, but spare embryos avoid repeating stimulation

What Is a “Freeze-All” Cycle?

A freeze-all (or “elective freeze”) cycle is when all viable embryos are frozen after retrieval and no fresh transfer is done — the transfer is deliberately postponed to a later, optimised cycle. It has become a cornerstone of safe, modern IVF and is typically recommended when:

• There is a risk of ovarian hyperstimulation syndrome (OHSS) — freezing avoids the pregnancy hormones that can make OHSS worse.
• Progesterone rises too early in the stimulation cycle, which would reduce a fresh transfer’s chance of success.
• You are undergoing genetic testing (PGT/PGS) and embryos must be frozen while results are prepared.
• The uterine lining is not optimal, or a medical issue needs treating before pregnancy.

When Fresh Transfer May Be the Better Choice

Frozen transfers get a lot of attention, but fresh transfer remains an excellent option for the right patient. It may be recommended when:

• You respond moderately to stimulation, with a normal number of eggs.
• Your hormone levels and uterine lining are ideal on the planned transfer day.
• You are not undergoing genetic testing.
• You prefer the shortest path to pregnancy and, in some cases, a lower cost for that cycle.

Safety and Baby Health: Is One Safer?

Both approaches are well established and safe. A few evidence-based points worth knowing:

• OHSS: Freeze-all FET almost eliminates the risk of severe OHSS, because retrieval and transfer are separated.
• Birth weight: Some studies associate FET with a lower chance of low birth weight and preterm delivery compared with fresh transfer.
• Balance: Certain hormone-prepared FET cycles have been linked to a slightly higher chance of some pregnancy conditions, which is one reason your specialist chooses the protocol carefully.

In short, neither is “risky” — the safest choice is the one tailored to your body and history.

So, Which Should You Choose?

The takeaway is reassuring: you don’t have to choose alone, and there is rarely a wrong answer. Your fertility specialist looks at your age, ovarian response, hormone levels, uterine lining, whether you need genetic testing, and your personal preferences — then recommends the approach most likely to give you a healthy baby. Very often the plan is a hybrid: a fresh transfer if conditions are ideal, with any remaining good embryos frozen for the future.

Frozen & Fresh Embryo Transfer at Myra IVF Centre, Kenya

At Myra IVF Centre, we personalise the transfer decision for every patient rather than applying a one-size-fits-all rule. Our care includes:

• Personalised transfer planning based on your hormone response, lining and embryo quality.
• State-of-the-art, ISO 9001 certified embryology laboratory using vitrification for high embryo survival.
• Freeze-all and elective FET protocols to protect against OHSS and maximise success.
• Advanced options — blastocyst culture, assisted laser hatching and genetic testing (PGT/PGS) where appropriate.
• Secure long-term embryo storage for future pregnancy attempts.
• Three convenient locations — Nairobi, Mombasa and Kisumu.

With over 15 years of experience and a 79% overall IVF success rate, Myra IVF Centre has helped thousands of couples across Kenya and East Africa build their families.

Conclusion

Frozen and fresh embryo transfers are both powerful, proven paths to pregnancy. Fresh transfer offers a faster route when your body is in ideal condition, while frozen transfer can match or beat it for high responders, PGT cycles and anyone who benefits from a recovered, better-prepared uterus. Thanks to vitrification, freezing no longer means compromise. The real key to success is a personalised decision made with an experienced fertility team.

If you’re weighing up your options, speak with our fertility specialists at Myra IVF Centre — we’ll explain exactly which transfer gives you the best chance, and why.

Book a consultation today. Contact us at +254 786656236 or drsarita2007@gmail.com.