Aug 12, 2025

Freezing eggs at 28 vs 35: why timing changes everything

When it comes to fertility, science is clear: timing matters. That doesn’t mean you need to panic, rush, or “have it all figured out.” But if you’re even thinking about egg freezing, knowing the difference between doing it at 28 vs 35 can help you make one of the most informed and self-loving choices of your life.

Let’s walk through how egg freezing age timing can shape your fertility outcomes - and what it means for your body, your future, and your options.

Freezing eggs at 28 vs 35: why timing changes everything

What does egg freezing actually do?

Egg freezing (also called oocyte cryopreservation) preserves your eggs at their current age and quality, so you can use them later - if and when you decide to. It’s not a guarantee, but it is a powerful fertility safety net. Since age-related fertility decline becomes more pronounced in your 30s, freezing your eggs - whether at 28 or 35 - can help you keep reproductive options open, even if life doesn’t follow a set timeline.

 

 

How Age Affects Egg Freezing

Why does age matter so much? Because your egg quality and egg quantity - also known as your ovarian reserve - naturally decline with age. This decline accelerates after 30.

Here’s what the ovarian reserve timeline typically looks like:

  • At 28: You still have a relatively high egg count, and about 70–80% of your eggs are chromosomally normal.

  • At 35: Your reserve starts to drop more noticeably, with only about 50–60% of eggs chromosomally normal.

  • By 38+: Both quality and quantity fall sharply, with less than 30–40% of eggs likely to be genetically viable.

This impacts egg freezing success by age, IVF outcomes, and how many cycles you might need to reach your fertility goals.


Freezing Eggs at 28

Freezing Eggs at 35

✅Higher ovarian reserve and egg quality at 28

✅~70–80% chromosomally normal eggs

✅Less medication needed for stimulation

✅Fewer cycles at younger ages. So you have greater chances of completing in one cycle 

✅Lower emotional and physical stress

✅More cost-effective in the long run

✅More flexibility for multiple pregnancies later

 ➡  Benefits of freezing eggs at 28: Fewer interventions, stronger odds per egg, and better IVF outcomes when you decide to use them.

✅Still possible and widely practiced

✅You may have more clarity on your goals (partner, family, timeline)

⚠️Egg quality declines (~50–60% chromosomally normal)

⚠️More likely to need multiple cycles

⚠️Higher medication doses and costs per viable egg

⚠️More emotional and physical stress

 ➡ ️ Freezing eggs at 35 worth it? Yes - but expectations and strategy matter. For many women, this is a now-or-never fertility window.


 

 


Your Egg Freezing Questions, Answered

Q. How many eggs do you need?
The number depends heavily on your age and egg quality. For one potential live birth, the general guide for the number of eggs needed by age looks like this:

  • Age 28–30: 10–15 eggs

  • Age 31–34: 15–20 eggs

  • Age 35–37: 20–25+ eggs

  • 38+: 30+ eggs, often across multiple cycles

This difference comes down to egg survival rates after thawing, fertilisation rates, and the likelihood of each egg becoming a healthy embryo.

➡️ Number eggs needed freezing age 28: often achieved in one cycle
➡️ Number eggs need at 35: may take two or more cycles, especially with low AMH


Q. Is it more cost-effective to freeze earlier?
Yes. While per-cycle egg freezing prices are similar whether you’re 28 or 35, younger women often freeze enough eggs in one round – saving on medication, monitoring, and emotional energy.

If you’re asking what’s the most cost-effective egg freezing age - it’s typically in your late 20s to early 30s, before your ovarian response starts to decline.


Q. What does this mean for IVF success?
Freezing earlier means more chromosomally normal eggs, which leads to stronger embryos and higher success rates with IVF later. IVF outcomes from frozen eggs are tied to the age you froze them, not your age at transfer.



Updated August 12, 2025