Average number of blastocysts per IVF cycle

It’s a really simple question – what is the average number of blastocysts per IVF cycle?  After our failed IVF cycle I posted a status update in my local resolve support group’s facebook page, I explained what had happened with our cycle: 14 eggs retrieved, 11 mature, 11 fertilised, 2x 5 Day blastocysts transferred (5BB & 5CC) on Day 5, 9 still alive on day 5, but 0 were of sufficient quality for cryopreservation.   Some ladies commented how they had similar results with 0 embryos making it to the freezer, and one lady posed the very good question how common is it to have 0 make it to the freezer? Perhaps it is more common than we think?  So it got me thinking…at no point has my doctor said what a typical number of eggs, embryos or blastocysts she would expect out of a cycle for us – the only stats we were ever told was all about our likelihood of a successful pregnancy from 1 cycle of IVF, and ultimately, a live birth.  And of course, that is the only statistic we only really care about, right?  This holds true, until you get a Big Fat Negative (BFN), then the other statistics start to matter and grind at you.

So I looked into it, and asked google – what is the average number of blastocysts per IVF cycle?  But I couldn’t find an easy answer, or at least one that I held great confidence in.  I’m the kind of person who needs to see the supporting evidence, and not just some seemingly arbitrary numbers some random person has posted on a website.  But although I didn’t find any national statistics per se, what I did find, made me feel a whole lot better about our last cycle.

The statistics that the Pacific Fertility Center in Canada are claiming are [1]:

11 – Average number of eggs retrieved

9 – Average number of mature eggs

7 – Average number of eggs that fertilise (approximately 80%)

7 – Average number of fertilised eggs that will form embryos (98%)

7 – Average number of embryos on Day 3 of culture

3.5 – Average number of blastocycts on Day 5/6 (50% of good quality day 3 embryos make it to blastocyst)

It was not clear if this was their clinic’s statistics or where the source of this data came from.  So my confidence is not high in it, I don’t know over how many cycles or patients this average is calculated.  But at least it gives you a flavour of what numbers to expect.  Note, it does not mention average number of blastocysts making it to cryopreservation!

Another clinic, Advanced Fertility Center of Chicago, provides a nice pretty chart of their own statistics, broken down by age for the period of 2003-2005.  First of all my first alarm bell is that is over 10 years old now!  Has anything changed in Assisted Reproductive Technologies in the last 10 years? Hmmmmm.  Anyway, here it is….


Advanced Fertility Center of Chicago’s average number of eggs, mature eggs, fertilised eggs, 8 cell embryos and Day 5 blasts [2]

Their numbers are slightly lower than the Canadian clinic’s…but there could be many reasons for this because, again, there is no clue as to how many cycles/patients this average is calculated over.  This clinic does publish their statistic of how many blastocysts make it to cryopreservation.  And here is the money shot statistic people!!!!


Advanced Fertility Center of Chicago’s average number of blastocysts frozen per cycle in 2010-2011 [3]

Just look at how low these numbers are! An average of 1.7 for women younger than 35 years old.  And this statistic is a little bit more up to date than the ones above – this was for cycles from 2010-2011.

So what is the point of this post?  The point is that we didn’t have any blastocysts that made it to cryopreservation, but we did have 2 blasts that were transferred and 1 that could have been frozen, but they decided it might not survive the thaw.  For our first cycle we had one blast make it to the freezer.  The point is, we had high expectations for more to make it to the freezer, when in actual fact the reality is, we were better than average to have so many good Day 3 embryos and we were typically average with transferring 2 on Day 5. Yes, IVF cycle 2 was a failure, but we were pretty average with our second cycle!!! This doesn’t mean we are less likely to succeed with cycle 3, rather the odds ARE in our favour.

Happy dance Dani!!!

stay the path

[1] Source: http://www.pacificfertility.ca/our-resources/guide-to-ivf-lab-results/

[2] Source: http://www.advancedfertility.com/ivf.htm

[3] Source: http://www.advancedfertility.com/cryo.htm



24 thoughts on “Average number of blastocysts per IVF cycle

  1. Nara says:

    That’s really interesting. I’ve been wondering the same, as we didn’t have any to freeze either, and I felt pretty bad about it. We had 12 eggs retrieved, 6 fertilised, 3 on day 3 and only 1 on day 5. I always feel like that was really bad… Maybe it’s not as bad as I thought!


  2. g2the4thpower says:

    It seems to vary a lot from clinic to clinic as to what they consider to be freezer worthy. I know both my clinics I used for IVF (in Canada) discard unless by day 6 or 7 things start to look good. One blogger I followed a while back had over 20 that went to freeze, and I have no clue how that could happen. It makes me very curious about the quality difference.


  3. g2the4thpower says:

    From my cycle 1: 15 retrieved, 5 mature, 0 fertilized. Devastating. Cycle 2: 9 retrieved, 5 mature, 5 fertilized, 1 crappy 5dt, 0 frozen, BFN. Cycle 3: 19 retrieved, and 14 mature, 9 fertilized, 1 beautiful 5dt, BFP, 0 frozen.


  4. EmilyMaine says:

    It is really interesting to read all this. I had a friend who was at the same first clinic as me and she froze 10 or something. She did 4 transfers before she got a baby though (and some of the early transfers resulted in chemicals). That same clinic told me to expect 5-6 blasts (I have a high AMH) but they were so wrong. It really is a case by case thing and there will always be outliers so I can see how these stats might be about right.


  5. Surviving Infertility says:

    Thanks for educating me some more in this area. We had 19 retrieved, 11 fertilized, 8 made it to day 6 blasts, and 7 were frozen. All graded high. More than average and I still havent got our baby home yet. I have learned to hate statistics bc I always go against them (and not in a good way)


  6. Amy M. says:

    I really wish there was more info published out there about this stuff. You’d think with all the women all over the world that are going through this stuff, that they would be able to gather all the info and get some better numbers for us to pore over!


  7. Baby, Are You Coming? says:

    Pacific fertility was my clinic! Our first cycle, we had 14 mature eggs, 10 fertilized, and ended up with 1 day 5 transfer and two frozen. One was 4bb and the other was 4bc. The second one I don’t think actually survived the the because it was fully expanded when transferred.

    Our second cycle we had 10 mature eggs, 10 fertilized, transferred two day 5 4AA and have three in the freezer.


  8. Babyscienceproject says:

    Over 5 cycles of own-egg IVF I only ever had ONE blastocyst make it to the freezer….and it failed to thaw. Who really knows why? I’m pretty convinced that my own eggs were rubbish although they may have ‘looked’ great (I quickly stopped listening to docs when they told me that I had X number of great/perfect/wonderful embryos). Fact is, you’ve had 1 almost success and 1 failure so far. Most clinics in the UK recommend 3 cycles before you try anything majorly different. Try not to obsess over the freezer and how ‘good’ your embryos looks, it will drive you MAD. It’s good that you’ve managed to find a tiny amount of data out there in IVF la-la land. I really hope this next cycle works out for you….stats look promising, right?


    • RABS says:

      Dont tell me.. There can be issue with thawing.
      I have 5 Blastocyst in freezer. I didnt know there can be some problem with thawing as well. Going for transfer in next month. Hoping for best. Rather my hopes are very high that makes me scared as well.


      • thegreatpuddingclubhunt says:

        My doc preferred not to do a transfer with just one in the freezer (our one and only Frozen embie I’m paying $60 a month to keep!!!) because of the thawing thing, but 2 was the goal, so I think statistically speaking the survival rate through the thawing is very good for day 5 embies.


  9. Anonymous says:

    We were told by our clinic that on average, for every 5 mature eggs retrieved from a donor, 1 would result in a blastocyst. I’ve never seen this figure published anywhere; it’s just what the staff (including doctors) at our clinics say. The is supposedly average ratio sounds very low to me for donor eggs. I don’t know if the clinic is just trying to contain and manage expectations. In our case, we did a little better than this supposedly average ratio, with roughly 25% of the mature eggs from our 23-year-old donor making it to the blastocyst stage.

    Liked by 1 person

  10. lindsey says:

    i had 36 follicles, 30 eggs retrieved, 21 survived fertilization ending with 10 perfect graded 6 day old blasts. I do have PCOS and i did get moderate OHSS so my transfer was cancelled. We are now starting process for frozen transfer.


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