What Age Should You Freeze Your Eggs? The Numbers That Matter (2026)

Egg freezing demand is growing 20% year-on-year in the UK and Australia. The average age at freezing is 37. But what does the data say about when to do it? This is not a recommendation. It is the numbers.

Success rates by age at freezing

The age at which you freeze your eggs is the single most important variable in future success. Egg quality declines with age, and no amount of money or technology can reverse that decline once eggs are collected.

| Age at freezing | Live birth rate per thaw cycle | Egg survival (thaw) | Fertilisation rate | |----------------|-------------------------------|---------------------|--------------------| | Under 30 | 35-45% | 90-95% | 70-80% | | 30-34 | 30-40% | 85-95% | 65-75% | | 35-37 | 20-30% | 85-90% | 60-70% | | 38-40 | 10-20% | 80-90% | 50-65% | | Over 40 | Under 10% | 75-85% | 40-55% |

These rates come from HFEA (UK), ANZARD (Australia), and published meta-analyses. They represent averages across clinics. Individual clinic results vary.

Number of eggs needed by age

The goal is typically 15-20 frozen eggs for a reasonable (approximately 75%) chance of at least one live birth. But the number needed increases with age because each individual egg is less likely to succeed.

| Age | Eggs for ~75% chance of 1 baby | Eggs per cycle | Cycles needed | |-----|-------------------------------|----------------|---------------| | Under 30 | 12-15 | 12-20 | 1 | | 30-34 | 15-20 | 10-15 | 1-2 | | 35-37 | 20-25 | 8-12 | 2 | | 38-40 | 25-30 | 5-8 | 3-4 | | Over 40 | 30+ | 3-6 | 5+ |

At 30, one cycle might be enough. At 38, you are looking at 3-4 cycles to collect sufficient eggs. At 40+, the number of cycles required makes the endeavour extremely expensive and still uncertain.

Cost per baby by age

This is the number that matters most: what does egg freezing cost per successful baby, factoring in the number of cycles needed, storage time, and success rates?

| Age at freezing | Cycles | Cycle cost (UK) | Storage (10yr) | Thaw + IVF | Total spent | Success rate | Cost per baby | |----------------|--------|-----------------|----------------|------------|-------------|--------------|---------------| | 30 | 1 | £5,000 | £3,000 | £3,000 | £11,000 | ~38% | ~£29,000 | | 34 | 1-2 | £7,500 | £3,000 | £3,000 | £13,500 | ~32% | ~£42,000 | | 37 | 2 | £12,000 | £2,000 | £3,000 | £17,000 | ~25% | ~£68,000 | | 40 | 3 | £18,000 | £1,500 | £3,000 | £22,500 | ~8% | ~£281,000 |

These are illustrative estimates using mid-range UK pricing. Australian equivalents are roughly 1.8x in AUD. The "cost per baby" divides total spending by the probability of success.

The catch-22 of timing

There is a fundamental tension in egg freezing timing:

Freezing younger (28-33) gives you:

• Highest egg quality and success rates
• Fewest cycles needed (lower upfront cost)
• More eggs collected per cycle
• The best biological insurance

But also means:

• More years of storage fees ($150-400/year UK, $300-600/year AU)
• Highest probability of never using them (you may conceive naturally)
• Longest gap between paying and potentially benefiting
• Money spent that could have been invested elsewhere

Freezing older (36-40) gives you:

• Lower storage costs (shorter time to likely use)
• Higher probability of actually needing the eggs
• More certainty about life circumstances

But also means:

• Lower egg quality and success rates
• More cycles needed (higher upfront cost)
• Fewer eggs per cycle
• Significantly higher cost-per-baby

The average age is 37: what does that tell us?

The average age of egg freezing in both the UK and Australia is 37. This is not because 37 is optimal. It is because:

1. Financial readiness tends to arrive in the mid-to-late 30s
2. Awareness of declining fertility often comes after 35
3. Relationship status becomes a clearer factor by this age
4. Medical guidance from GPs typically triggers after 35

The data suggests that if the decision is going to be made, earlier is statistically better. But the decision itself is personal, not purely statistical.

What about never using them?

This is the number that rarely gets discussed: only 10-15% of women who freeze eggs ever return to use them. The rest either:

• Conceive naturally with a partner (most common)
• Decide not to have children
• Use donor eggs or adopt
• Run out of financial resources for thawing and IVF
• Allow storage to lapse

This means for 85-90% of women who freeze, the money spent is an insurance premium that was never claimed. Whether that insurance was "worth it" depends on the peace of mind it provided and your personal financial situation.

Age-specific decision data

Age 28-32: Biologically optimal, practically uncertain

Success rates are highest. One cycle is usually enough. But at this age, many women are still partnered or expect to conceive naturally. The probability of never using frozen eggs is highest in this group (estimated 90%+). The financial argument: spend £5,000-8,000 now for the best biological insurance, knowing you will likely never claim.

Age 33-36: The pragmatic window

Success rates are still strong (25-35% per thaw cycle). Most women need 1-2 cycles. Life circumstances are more defined. The probability of needing the eggs is higher than at 28. Many fertility specialists consider this the practical sweet spot — good enough biology, clearer personal circumstances.

Age 37-39: Diminishing but meaningful

This is where most women actually freeze. Success rates drop to 15-25%. Two or more cycles are typically needed. The cost is higher, the odds are lower, but there is still a meaningful chance of success. The question becomes: is 20-25% worth £12,000-18,000?

Age 40+: Unfavourable numbers

Under 10% success rate per thaw cycle. Multiple cycles needed (3+). Very high cost-per-baby. At this age, going directly to IVF with fresh eggs may be more cost-effective if you have a partner or are willing to use donor sperm. The data does not support egg freezing at 40+ as a cost-effective strategy for most women.

What the data says

If you strip away the personal circumstances and look only at the numbers:

1. Earlier is statistically better — every year before 35 improves success rates and reduces total cost
2. The practical window is 30-36 — balancing biology with life certainty
3. After 38, returns diminish rapidly — still possible, but increasingly expensive per unit of success
4. Most women never use frozen eggs — it is insurance, not a plan
5. The financial comparison is egg freezing vs IVF at 40 — if the alternative is needing IVF later, early egg freezing is cheaper per baby

But these numbers cannot capture: peace of mind, relationship dynamics, career timing, or the personal value of having options. The data informs the decision. It does not make it.

UK and Australian costs compared

| Factor | UK | Australia | |--------|-----|-----------| | Cycle fee | £2,500-5,000 | $4,000-8,000 | | Drugs | £1,000-2,500 | $160-285 (PBS) | | Storage/year | £150-400 | $300-600 | | Medicare/NHS rebate | NHS only for medical | Medicare only for medical | | Storage time limit | 55 years (since 2022) | No limit |

The biggest difference: Australia's PBS subsidises medications regardless of indication, saving $1,200-2,700 per cycle. The UK has no equivalent subsidy for elective egg freezing drugs.