Flushed a unfertilized egg...should their be an embryo with it?

[kaispen]

So the vet found an unfertilized egg after my mare’s embryo flush today. Everything went perfectly with insemination(excellent semen, huge follicle) and the vet followed up until she ovulated within 36 hours. 8 days later, no embryo, but an unfertilized egg. We are attempting another flush tomorrow to see if there is an embryo perhaps still making its way to the uterus, as my vet explained that it can happen that the embryo carries the other egg with it through the fallopian tube (that otherwise it would not normally travel that far on its own).

Anyone ever experienced this? What was the final result? Im very new at this and would like to learn more and hear about others’ experiences/trials/heartache.

[back_in_the_saddle]

[QUOTE=kaispen;8650907]
So the vet found an unfertilized egg after my mare’s embryo flush today. Everything went perfectly with insemination(excellent semen, huge follicle) and the vet followed up until she ovulated within 36 hours. 8 days later, no embryo, but an unfertilized egg. We are attempting another flush tomorrow to see if there is an embryo perhaps still making its way to the uterus, as my vet explained that it can happen that the embryo carries the other egg with it through the fallopian tube (that otherwise it would not normally travel that far on its own).

Anyone ever experienced this? What was the final result? Im very new at this and would like to learn more and hear about others’ experiences/trials/heartache.[/QUOTE]

The embryo would have been in the uterus by 8 days - if there was an embryo. What was the timing of insemination compared to ovulation? Fresh or frozen? Was the breeding pre or post ovulation?

I don’t know the answer to your question if there was an embryo with the unfertilized egg. But, I have heard that is when vets know to keep looking for an embryo. Is that a 100% sign? I don’t know.

[kaispen]

The mare was bred with fresh within 8 hours of collection, and ovulated between 16 - 34hrs post insemination. Healthy 8 year old mare, fertile stallion.

We did a second flush today, but still no embryo. Everything else went perfectly. I am more shocked than anything and can’t rationalize a second attempt when there is nothing to improve upon. She should have produced an embryo! Now to see if she comes back into heat…!

[back_in_the_saddle]

[QUOTE=kaispen;8651921]
The mare was bred with fresh within 8 hours of collection, and ovulated between 16 - 34hrs post insemination. Healthy 8 year old mare, fertile stallion.

We did a second flush today, but still no embryo. Everything else went perfectly. I am more shocked than anything and can’t rationalize a second attempt when there is nothing to improve upon. She should have produced an embryo! Now to see if she comes back into heat…![/QUOTE]

I’d pinpoint ovulation better and breed closer to ovulation. 16-34 is a huge span of time. The vet should have had a much closer range of time. More like 4 hour time span.

When did you culture her? During the heat cycle or in between heat cycles? I ask because my mare had an infection that only showed up on culture during the heat cycle. Many cultures came back negative that were taken in between her heat cycle.

[flyracing]

Inseminating sometime within 36 hours of ovulation is not the norm for ET (or other time when the mare taking on that insemination is important). We have a goal of a two hour window. Not only is that important for increasing the chances of success, but the window of ideal flushing time is also smaller than 36 hours! The person you’re using for ET needs to be much much more proactive and precise!

Side note: when she hadn’t ovulated 24hr post breeding, a 2nd collection would have been best if possible. The cost of a 2nd cycle of ET attempt is more than the 2nd collection depending on your contact with the SO.

[epowers]

I’m blown away that anyone would waste money on an ET with a vet who can’t pinpoint the window for ovulation any narrower than “sometime within 36 hours of being inseminated”. You should not be shocked to not have recovered an embryo, but you might want to look into a new vet! Sounds like using this one was just throwing money in the toilet, and wasting a cycle.

[back_in_the_saddle]

[QUOTE=epowers;8652800]
I’m blown away that anyone would waste money on an ET with a vet who can’t pinpoint the window for ovulation any narrower than “sometime within 36 hours of being inseminated”. You should not be shocked to not have recovered an embryo, but you might want to look into a new vet! Sounds like using this one was just throwing money in the toilet, and wasting a cycle.[/QUOTE]

Agree.

[kaispen]

Well I definately had no idea that inseminating so close to ovulation when using fresh was so vital. I always understood that good - great quality semen was at least good for 24hrs up to 72hrs, or something like that. I agree that doing an ET means tweaking a few things, definately! I am a first time breeder and was going on the advice of others. Unfortunately I was 2hrs away for the vet to travel for all the work done and it had been greatly recommennded to bring my mare to the clinic to do the breeding/transfer. I couldn’t. I assume some responsibility for not being conveniently located at such a hectic time for repo vets. However, I was prepared to AI again when the first ultrasound at 16hrs post insemination showed she had not yet ovulated but was advised that the semen was excellent and would still be effective. The next day ultrasound at 36hrs showed she had ovulated sometime before but we were ready to inseminate again at this time (with more semen on hand) which we then did not use.

There was no culture done.

Why the oocyte?

The vet I used does a TON of ET’s so I felt very comfortable using this team of repo vets. If I were to do it again I think I would bring my mare to the clinic, but alas it was a one time shot for me. I guess its all a learning process!

[epowers]

It’s not even a matter of inseminating close to ovulation (though that helps). If the semen is good its not at all unheard of to last longer than that, and if you were breeding the mare to carry it probably would have been fine. It’s that to do an embryo flush you NEED to know exactly when ovulation occurred, definitely within a few short hours, because there is a small window for being able to successfully flush an embryo. The fact that the vet didn’t care enough to bother ultrasounding every few hours to confirm ovulation should be a huge red flag. I’d seriously find another vet unless you just enjoy throwing money out the window. I can’t imagine he does a lot of successful ETs with these kind of practices.

[back_in_the_saddle]

Maybe they missed seeing it in the Petri dish? IF she ovulated 34 hours later, conception happened after that right? So we’re talking a day+ of growth smaller than a true eight day gestation embryo. This is why they need to know within a closer range than (sometime between 16-34 hours later) of when ovulation happened.

[RanchoAdobe]

Even with exact timing of ovulation with repro experts it is not “abnormal” to flush an unfertilized egg. Sometimes the semen just does not do its job. I have done a number of ET’s and that has happened to me once over the past three years. However, I would agree with above posters that not being able to pinpoint ovulation would make me extremely nervous for the reasons stated above.

[kaispen]

Okay so just for my own knowledge here, if we knew at 16hrs she hadn’t ovulated but knew at 36hrs that she did, then that means we know that she ovulated within a 20hr window. That to me means we know what day, or span of time we can consider a day, that she ovulated, and therefore know which day would constitute as day 7 or day 8 for flushing. So why is it then so important to know the exact hour or a narrower timeframe then the actual 20hrs? From the studies i’ve read day 7 - 8 and even 9 are successful flush days as long as the recipient is properly synchronized…therefore our estimation of the timing of ovulation should be enough to determine day 7,8,9. No?

I never intentionally throw my money away

Thanks for the responses! I love to learn.

[kaispen]

Back in the saddle, that makes sense. I believe thats why they waited t’ill day 8 to do the flush. I questioned this as well as I had expected to flush on day 7, but I was told that they like to wait an extra day with fresh inseminations.

[back_in_the_saddle]

Did they start the 8 day count down from the time of insemination or the time of the last check? I’m not clear when the 8 day count started.

Just for a comparison, my mare was bred on May 4 with frozen, her flush will be on May 12th.

I “believe” the smaller the embryo the more success the transfer is.

If ovulation happened early in the 20 hour span, and the 8 day flush was from the last check, the embryo is 8 days +20ish hours +actual time from conception however long that was correct? If the clock started at the last check and ovulation happened an hour before the check then the embryo was an 8 day embryo.

It doesn’t sound like there was an embryo as I would have expected one to have been recovered with two flushes. But I have no idea how hard it is to miss one in a flush.

[keysfins]

The relevant timing, for ET, comes from the time of ovulation, which is why it is so critical to know that window. And in as small a timeframe as possible, NOT a 20 hour timespan. Your repro vet should have explained this to you. Your “flush window” corresponds to your “time of ovulation window”, not with whether your semen is capable of fertilizing an egg, or for how long.

It is the release of the egg, ovulation, that starts the clock for when to flush when doing ET, and that’s why it is crucial to know when that happens. Does that make sense?

If you are not doing ET, and the mare is going to carry the pregnancy, then the timeline does not need to be so precise. And you can inseminate pre/post-ovulation, because the semen will be happy to hang around just waiting for that egg. So then you just hope that the egg is fertilized, and that the result is a pregnant mare.

If I understand that your business travel prevented the vet from coming out to check when your mare actually ovulated, you might do better to have the mare at the Repro clinic to “follow the follicle” more closely, with more frequent ultrasounds, if you intend to try again.

BITS, good luck with your flush!!

[keysfins]

One more question for the OP: did the mare have other follicles developing when she was inseminated?

[keysfins]

[QUOTE=kaispen;8654649]
Back in the saddle, that makes sense. I believe thats why they waited t’ill day 8 to do the flush. I questioned this as well as I had expected to flush on day 7, but I was told that they like to wait an extra day with fresh inseminations.[/QUOTE]

Do you know if the mare had other follicles developing when she was inseminated?

[kaispen]

Keysfins, I couldn’t take her to the clinic as she is on a lease and I needed to honor that first. The vets were unfortunately very far from the mare’s location so I know now that the distance was an issue. My fault, I had no idea this would be so critical.

The 8 days was counted from the time of our last ultrasound (afternoon of the 27th) where she had ovulated since we know she had sometime in the 20hrs previous. That would make the timing greater than 7 days and slightly under 8 (flushed in the morning of may 5th and again on the 6th). Its the vets common practice to flush on day 8 with fresh inseminations.

Next time I will definately have the mare at the clinic. Probably not this year though

[kaispen]

There were no other follicles developing and she had been teasing for 6 days once she ovulated so im sure there weren’t any that developed after the last ultrasound…but who knows for sure?!

I realize now that had she ovulated at the beginning of the 20hrs then we would have been flushing too early and there may be a chance that embryo was missed. However, would we not have missed the unfertilized egg as well then? Is it not the same size or smaller?

I totally ‘get it’ now. It pays to have knowledge yourself in these situations, doesn’t it?

BITS, good luck!

[Hillside_H_Ranch]

I haven’t read through all of the replies but it would be very uncommon to recover a UFO (unfertilized oocyte) without an embryo being produced. In fact, when a UFO is present, one always keeps looking for an embryo. An embryo can be missed, or not flushed, or a UFO can be mistaken for an embryo (or vice versa) but unfertilized oocytes generally don’t leave the oviduct without an embryo. That being said, you do NOT need to record ovulation within a few hours to know when to flush for an ET. You do need to know the DAY of ovulation, to calculate the day of the flush. All of that being said, in this case, I would assume an embryo was missed, or your oocyte was actually an embryo.