Educational Post: Twins

[Regret]

Since so many of us witnessed what happened with Sassy and her twins on cam, I wanted to create a thread that was informational on the subject of twins in equines. Please feel free to ask questions if you want them answered and established breeders, please feel free to add your input. This thread is inspired by this post by Darlyn from Fairview Horse Center, which was buried and then deleted in the original Sassy thread:

Yes, if they are close together, many times one will eliminate, but that is not going to happen after 6 months. At 6 months, one twin should have been dealt with by injection by a qualified professional. It has a VERY good success rate. If not, the pregnancy should have been aborted at that point while the fetuses were small enough to be easily delivered.

IF you find a twin late term, then the mare owner needs to make sure they take the mare to a facility so vets are on site to be able to assist immediately to save the foal(s) and mare. These facilities are equipped to be able to sedate the mare to stop contractions from constantly slamming the foal to the back, blocking the small opening, raise her back end to allow gravity to shift the foal away from the tract to give room to reposition the foal(s) for safe delivery.

I say this not to be mean, or hurtful, but so everyone can learn what to do to save many other mares and owners from going thru the same pain and tragedy.

Horse breeding is not for the faint of heart-- things happen and mistakes are made, but every situation is one that we can inevitably learn from.

THIS IS NOT A THREAD TO PLACE BLAME. If you feel like you need to make a post that is blaming anyone or negative in context, it will be promptly deleted. This is not the time nor the place for that kind of posting.

This is about learning, and Mare Stare is the kind of community that will help newcomers learn what they are watching. Breeding is full of joys and wonders, but also tragedy. We can learn from EVERY experience, and I want to take this opportunity to find an educational venue for the posts that may have been deleted during the fiasco that this board endured by many people who didn't understand fully what was going on. This is the place for that.

Please, ask questions and learn from this experience. Breeders and owners-- please share your experiences and your expertise.

Thank you.

[risingrainbow]

I thought I knew a lot about twins before my mare had them. I found out I knew piratically nothing. But I've made it my business to learn everything I can since then.

Watching the thing with Sassy unfold, it was clear to me that there was a lot of misinformation out there. That and there were many assumptions that were made along the way.

This quote above for example about dealing with one twin with an injection. I've not been able to find any information on the Internet or from talking with a number of vets about any kind of mid term or late term method of disposing of one twin by injection or any other means and preserving the second foal.

It was also suggested on the old thread that the mare should have had an abortion when the twins were detected at 6.5 months. That, too, is not an option that I am aware of, nor could I find information on the web. To the contrary, I found information suggesting mid or late term abortion is dangerous in the mare. The major vet hospitals here would not be involved in such a procedure.

The other thing that is very important to consider here is what one person has available to them for resources may not be available to another person. I live near a large metropolitan area, there are two major vet schools within a 5-6 hour driving distance. I know from personal experience that those schools don't have much experience with twins.

There is a procedure to eliminate twins that involves a needle being placed into the brain of one of the twins and aspirating the matter. That procedure must be done early in the first trimester. And neither of these schools vet hospitals does this technique. To my knowledge it is available in Canada somewhere but nowhere within traveling distance here.

I've been doing a post for a number of days now on my blog trying to set the record straight about what happened with Sassy. Sorting through the facts and the things that got twisted and misinterpreted. risingrainbow.blogspot.com/2007/03/sassy-and-lauriettas-story-tradegy-or.html Please read the blog and then ask questions here if you have them.

Also, on the first thread someone posted a great link about why you would want to breed a mare with a history of twins. I thought I had saved it to my favorites but can't find it. Would sure appreciate that link. It was most useful in explaining the vets point of view on breeding a mare like Sassy. I'd love to have it for a resource.

[saddlebredlover]

www.equine-reproduction.com/articles/Twins.shtml

Here you go, MiKael.

[risingrainbow]

Thank you saddlebredlover for the link.

I forgot to add in my post in response to this
"IF you find a twin late term, then the mare owner needs to make sure they take the mare to a facility so vets are on site to be able to assist immediately to save the foal(s) and mare. These facilities are equipped to be able to sedate the mare to stop contractions from constantly slamming the foal to the back, blocking the small opening, raise her back end to allow gravity to shift the foal away from the tract to give room to reposition the foal(s) for safe delivery."

This assumes that all of us have this kind of treatment at our disposal. I can assure you, that's not the case. Many breeders are located too remote for such services. And the services are only available in a limited number of facilities because there is not that big a call for them. It's not available to me I've checked into it.

And the other issue here is finances. Not everyone can afford the expense of this type of care. I had an emergency fund when my twins were born. It took all of that fund, all of my show fund and I borrowed to pay the bills for the twins. The major facilites that could require that type of care require payment immediately, and some of them in cash. Costs are different in different parts of the country.Just the four days my twins were in the hospital cost nearly $4000 and had to be paid half up front the other half when I picked them up. That did not cover all of the things they wanted to do with them. The additional tests and x-rays were another several hundred more dollars. Colic surgery here starts at $10,000.

If you start saying the people who can breed horses are those that can afford to pay cash for catostrophic vet bills, then what you are saying is only the rich can breed horses at all. I don't think that's someplace we really want to go. But it is what the mandate from the quote above implies.

My feeling about this is it's really easy to sit back and second guess the decisions made when you don't even know all of the facts that relate particularly to that person and their available resources. It's not nearly so easy to live it.

[Allison]

Thank you for creating this thread! I know so many of, especially me, had so many questions about twin foals in Sassy's threads. I never even knew that a horse could give birth to twins! The first I had heard about it was when I watched Heiress foal and noticed MiKael's website and blog and then I found the little miracles Trouble and Surprise! It's such a fascinating thing in horsey life but definitely very scary. I will definitely go read those articles to learn more about the miracles that can happen and sadly the tragic realities that sometimes also happen too.

I have learned so much from the MS website and I am very grateful to have found it. I get to live my dreams of owning horses through you all and witness such blessed events. Although there have been some sad losses I have also seen I feel blessed to have met everyone on here and to have you all in my life.

[Blacklabs]

Thanks so much for this story, I read with tears and felt the rare emotions I felt that day watching.

I would like to post the link for the fund for Sassy if I could.

My prayers continue for Sassy and Laurietta


maremulligan.proboards40.com/index.cgi?board=windsong&action=display&thread=1174091774

[devotee]

When I saw this thread posted last night, I was hoping that MiKael would be an early voice on the subject, so I'm very glad to see her posts this morning. She has authority both from firsthand experience and comprehensive research. Beyond that, MiKael is level-headed and insightful, so I am always grateful for her stories and perspectives.

I cannot say anything about the specific case of Sassy because I was away during the foaling and the development of her entire thread. But I do have firsthand (traumatic!) experience with twins and I want to reiterate some of MiKael's points. I, too, live in a remote area that has difficult access to equine medical facilities and, frankly, lacks good vets and farriers. It's an ongoing nightmare. My thinking (and thinking and thinking) on the matter has always concluded that I need to maintain good relations with "local" vets who can get here in an emergency, so I'm partly stuck with their level of competency, at least for routine matters. My thinking has changed as a consequence of my twins experience and a couple more veterinary disasters after that, and I now use a vet who is 2 hours away . . . and my heart has permanently relocated into my throat. One thing about horses is that they will provide life with a steady stream of dilemmas . . . .

The local vet I used at the time of my twins disaster refused to ultra-sound my mare during the window for that after breeding. I begged him to do it on 2 occasions within the window. He told me to "play the odds." (He later told me, when the same mare became fatally afflicted with laminitis 10 years later, that I had to "play the hand you're dealt." Let me just say this: if your vet starts using gambling analogies, get a different vet.) During her pregnancy, I asked 2 other vets who happened to be on the farm where I boarded at the time to check her for twins, because I was worried about her size. Every local vet trivialized my concerns and told me to not to worry.

Ten months into her pregnancy, my (maiden) mare went into labor and foaled out a beautiful stillborn filly. As I stood there in her stall, sobbing and wondering what had gone wrong, she went down again, leapt to her feet, and shot out a second stillborn filly, answering my questions. Both fillies were perfect for their stage of development, although the second was smaller than the first. Neither had mummified. In retrospect, I guess I was very lucky that the delivery was so unproblematic. My ONLY concern at the time was for my mare. The experience was so traumatic that, after a couple more unsuccessful attempts to get her in foal, I gave it up. This mare was so precious to me that I would not put her at any kind of risk, and it was clear that continuing to breed her would involve some extra degree of danger to her.

My situation was not comparable to the one in question, because I was unable to ascertain that my mare was pregnant with twins. The villain in my case was veterinary irresponsibility. I don't really know what I can contribute to this conversation, other than a general lament about crises created by equine veterinary vicissitudes. Many horse owners are located in remote areas, operating small barns on shoestring budgets. These are all strikes against us, when it comes to procuring veterinary care. I know that horse vets lead difficult lives. I pay my bills and take meticulous care of my horses, but many in my area do not. Veterinary practices are shaped by those bad experiences, and I try to understand things from their perspective. I am an avid researcher and I keep well informed about every conceivable peril to my horses. I am competent and meticulous at performing ordinary horse care, including typical (and some untypical) injuries and illnesses. I am careful to make my expectations of aggressive veterinary care clear to my vets. But, in the end, I am stuck with what I can get.

MiKael's efforts to sift through all the contradictory information and lessons of experience are probably the the most comprehensive and insightful I've seen on the subject of twins. The dilemmas are rarely simple, and the remedies are rarely formulaic. I think that everybody can probably agree that it is unwise to allow a pregnancy with twins to proceed (I would NOT have done it!), but we are lucky if circumstances permit us to make that choice.

(And I am not a person who is comfortable relying on luck, but there it is.)

[cookiesmom]

Thanks folks for all the info. I really appreciate it. I applauded Laurietta's brave efforts with Sassy that day. We humans just cannot control for all the variables--twin pregnancies not discovered "soon enough" or not at all, ice storms and plain ole mother nature. I followed Rising Rainbows twins last year after I found out about them, was pleased to see a link this year and checked on them again, not too long before they were separated from each other. Mikael was such a wonderful caretaker of all of them. Glad to see she has posted here too! Keep up the great work all of you breeders and thanks for letting us into your barns. I have owned two mares now, one for six years and one for 9 months. I didn't and won't be breeding them because of my concern about the over population problem we may face and because of my lack of knowledge, lack of my own facilities and no way to realistically market foals, much as I would have loved a little Cookie to keep after I sold her to her new family where she's teaching little ones to ride. As for the new mare, don't know her potential yet and the same concerns as before also still apply. Trying to be a responsible, yet amatuer horse owner.
betsy

[maremidwife]

Yes, there is LOTS of misinformation out there.

originally posted by risingrainbow
"It was also suggested on the old thread that the mare should have had an abortion when the twins were detected at 6.5 months. That, too, is not an option that I am aware of, nor could I find information on the web. To the contrary, I found information suggesting mid or late term abortion is dangerous in the mare. The major vet hospitals here would not be involved in such a procedure."

The twins in question were not "detected" at 6.5 months, but "still there" then. Even so, aborting fetuses at 6.5 months is WAY less dangerous than attempting to deliver them at term, and ALL vet hospitals would do that rather than allow a twin pregnancy to continue. It does NOT get any safer, only more dangerous with each passing month. Twins that abort even at 9 months rarely cause a problem as their size is so small, they are easily delivered.

originally posted by risingrainbow
"This quote above for example about dealing with one twin with an injection. I've not been able to find any information on the Internet or from talking with a number of vets about any kind of mid term or late term method of disposing of one twin by injection or any other means and preserving the second foal.

Wapakoneta, OH is 8 hours from Cornell University. They were doing this procedure at least by 1990. It is done in MANY smaller more regional vet practices now with a high success rate. I checked it out last year for one of my mares. I have several practices offering this within 2 hours from me including Blue Ridge Vet - Dr David Barry. The cost as quoted was $500. last year. This is MUCH less than even a weeks worth of post foaling flushing and infusing treatments.

originally posted by risingrainbow
"There is a procedure to eliminate twins that involves a needle being placed into the brain of one of the twins and aspirating the matter. That procedure must be done early in the first trimester. And neither of these schools vet hospitals does this technique. "

Early in the first trimester, you can pinch a twin, unless they are right on top of each other, and you can still pinch, but an increased chance of losing both. That is why at that point, you wait to see of one eliminates within a few months on it's own. (85% will if that close) Injections are done when the fetuses are larger, not in the first few weeks. You can still abort with Lutalyse injections at about 5 months - probably for about $30.

re: financial issues
Obviously the longer you wait, the more it costs. A foaling mare that is attempting to deliver twins can be taken to a vet's facility that has a hoist. MANY small private vets are equipped. The costs are not like a large surgical facility. We all make financial decisions, and the decision to breed a mare is not one to be taken lightly. Losing a horse is also a financial loss and an emotional one. I am not sure why anyone would breed if the mare's value is not enough to justify some expense to save her. It may in fact be less to load her in the trailer and go to the vet when she starts labor, than having a long emergency call to the farm. Also, if we choose to breed on limited finances, we may have to make choices in giving up other things to cover needed vet care. That may include computers, internet connections, show expenses, buying more horses, etc.

[mamamare]

Greetings all,

This is my first post on the boards.

I had a mare that was diagnosed very late (9 months) in 1999. She had bagged up early and started to drip milk. We took her to our local veterinary hospital and had a trans abdominal ultrasound done that showed twins — one in each horn, approximately equal in size. It was recommended to me by the repro staff to electively abort the mare in the clinic for her own safety. I opted to follow the advice of those vets. The mare was injected with clenbuterol and shaped up as a normally foaling mare might in preparation of a normal foaling. She aborted the twins 3 days after the injection. At the time the major worries were dystocia (there was none) and retention of the placentas (they were passed quickly and safely). I was glad that the mare delivered safely and went on to have future foals.

I do not mean to second guess by posting here, but merely wish to give my own experience.

More on the elimination of twins:

In: Recent Advances in Equine Theriogenology, B.A. Ball (Ed.)
Publisher: International Veterinary Information Service (www.ivis.org)
Management of Twin Pregnancy in the Mare - After Endometrial Cup
Formation
(18 Apr 2000)
B.A. Ball
Department of Population Health and Reproduction, School of Veterinary Medicine, University of California,
Davis, California, USA.
Introduction
The advent of transrectal ultrasonography has dramatically improved the ability of veterinarians to accurately
diagnose and manage twin pregnancies in mares. As such the incidence of abortion due to twin pregnancy in
mares has declined over the past 10 to 20 years [1]. In spite of the improved accuracy of detection and
management of twin pregnancies in the mare associated with transrectal ultrasonography, twin pregnancies are
occasionally not diagnosed until after the formation of endometrial cups at approximately 35 to 40 days of
gestation. There are several potential reasons for failure to detect early twin pregnancies in mares:
1. Presence of (multiple) endometrial cysts
2. Too early detection of pregnancy such that one embryonic vesicle remains too small to detect with
ultrasonography
3. Incomplete examination of the entire uterus
4. Poor image resolution
5. Embryonic vesicles that are immediately adjacent but not properly identified as twins.
Fortunately, the incidence of twin pregnancies identified after Day 35 to 40 in mares is low, and veterinary
practitioners are infrequently required to deal with twin pregnancies in mares beyond Day 35 to 40.
Nonetheless, the high rate of abortions, poor neonatal viability, growth-retarded fetuses, dystocia and reduced
fertility in mares subsequent to twin abortions necessitates that twin pregnancies that are identified after Day
40 be managed in order to avoid these consequences.
There is little information available concerning the outcome of twin equine pregnancies after Day 40 beyond
that concerning the incidence of observed twin abortions or twin births in later gestation. Although
spontaneous reduction of twin pregnancies after Day 40 have been reported [2, 3, 4], the frequency of such
spontaneous reductions appears to be low. In 15 twin fetuses examined in pony mares, death of one fetus (two
mares) or both fetuses (8 mares) occurred during months 2 and 3 of gestation [3]. In the remaining mares, two
mares lost both fetuses during months 8 to 11, two mares lost one fetus during months 8 to 11, and only one
mare delivered twins at birth [3]. Although these observations are reported for pony mares, it appears that
some additional reduction of twin to singleton pregnancies can occur in mares after Day 40 of gestation. The
13% incidence of reduction of twin to singleton pregnancy in this study suggests that further reduction of twin
pregnancies can occur after Day 40 albeit at a low rate. These observations are further supported by the
author's observation in clinical cases of later twin pregnancy.
Several methods have been utilized in attempts to reduce twin pregnancies detected during the fetal stage of
pregnancy in mares. These methods include acute nutritional deprivation[5, transhoohool ultrasound guided
puncture of the conceptus [6], manual trauma or ballottement of the fetus [7], surgical removal of the
Page 2
conceptus [8], and transabdominal ultrasound guided injection of the fetus [7, 9, 10, 11]. This paper will focus
only upon the use of transabdominal ultrasound-guided fetal puncture as a method to reduce twin pregnancy
in mares.
Transabdominal Procedure
Transabdominal ultrasound-guided fetal puncture for twin reduction was originally reported by Rantanen and
Kincaid in 1988 [9]. In the original description of the technique, a fetal intracardiac injection of potassium
chloride was used to induce death of one fetus. Although effective, this approach is more technically
challenging, as it requires accurate placement of the KCl into the fetal vascular space in order to induce
cardiac arrest. Subsequently, McKinnon and Rantanen described the use of procaine penicillin G (PPG) for
intrafetal injection in order to induce fetal death [7]. This technique does not require precise placement of the
material in the fetal vascular space and fetal death can be induced by placement of the PPG into either the
fetal thorax or abdomen. McKinnon and Rantanen cite other advantages of PPG injection compared to KCl to
include: 1) reduced bacterial contamination, 2) PPG can be visualized ultrasonographically, 3) fetal death can
be induced without precise intracardiac placement of the solution.
Although no controlled studies have been conducted relative to the effects of gestational age on the outcome
of this procedure, Rantanen found a higher success rate when the procedure was conducted between day 115
and 130 of gestation [10]. Attempts earlier in gestation appeared to have a lower success rate whereas attempts
later in gestation appeared to be associated with more neonatal problems in surviving foals [10].
Technique
Careful evaluation of the twin pregnancy (Fig. 1) by transabdominal evaluation can be conducted with either a
5.0-mHz or 3.0-mHz transducer, although the 5.0 mHz transducer may not give adequate penetration to image
both fetuses particularly if one fetus is located more dorsal within the abdominal cavity (more likely with
earlier gestational age). Ultrasonographic evaluation of the twin pregnancy via transabdominal
ultrasonography requires that hair be removed (#40 blade) from an area between the udder to approximately
25 cm cranial to the mare's umbilicus. Many twin pregnancies between 90 to 130 days will be imaged in the
caudal abdomen, just cranial to the udder; however, sedation of the mare, particularly with acepromazine,
results in a profound uterine relaxation. After sedation, the fetal location often shifts cranially. Although it
may be useful to try to map the relative placental distribution of twins via transabdominal ultrasonography,
this is technically difficult. Most often, we infer the relative placental distribution of the two fetuses by
measuring fetal size. During this stage of gestation, a number of parameters may be used to assess relative
fetal size. These include diameter of the orbit, biparietal diameter, and thoracic diameter. Relative size and
location of the two fetuses should be carefully determined along with the orientation (cranial - caudal
presentation) of the fetuses in order to ensure accurate identification of the fetuses during and after the
procedure. The equine fetus is remarkably mobile during this stage of pregnancy and both fetuses can rotate
freely from cranial to caudal presentation. Size may be the best discriminator if there is a detectable difference
in the size between the two fetuses. If not, relative location should be determined, but keep in mind that these
locations will change.
Figure 1. Twin fetuses (arrows indicate thorax of each fetus) imaged by
transabdominal ultrasonography. To view this image in full size go to the IVIS website
at www.ivis.org .
After the fetuses have been evaluated for size, location and fetal heart rate, the mare should be sedated.
Originally, Rantanen described the use of a combination of acepromazine (10 mg), xylazine (100 mg) and
butorphanol (10 mg) as a sedative/analgesic for this procedure. This combination works well and appears to
give good uterine relaxation. This may be particularly helpful in those pregnancies that are carried high in the
caudal abdomen in order to facilitate better access to both fetuses.
Once the fetal parameters have been established, and the twin for reduction has been selected, the ventral
Page 3
abdomen overlying the twin is surgically prepared. In addition to the sedation and analgesia, a local
infiltration of lidocaine is used to provide analgesia at the puncture site. Although injection of the fetus may
be accomplished via a "free-hand" procedure using ultrasound, we prefer a 3.5-mHz ultrasound transducer
fitted with a biopsy guide (Fig. 2). An 18-gauge, 8-inch spinal needle with stylet can be used for most fetal
injections. The use of specialized needles with echogenic tips has been recommended by some authors to
facilitate visualization of the needle tip via ultrasound [7]. Once the fetal thorax is visualized, the needle is
introduced through the skin, abdominal wall and uterus into either the fetal thorax or abdomen. Injection of 10
to 20 ml of procaine penicillin G has been suggested to induce fetal death [7]. We typically use 15 to 20 ml of
PPG to induce fetal death in our practice (Fig. 3 & Fig. 4). Intrafetal injection (into either the abdomen or
thorax) does not result in immediate death of the injected fetus. In some cases, fetal death was not detected
(confirmed) until the day following the injection (Fig. 5).
Figure 2. Ultrasonogram of needle placement (arrow) into the fetal thorax. To view
this image in full size go to the IVIS website at www.ivis.org .
Figure 3. Injection of procaine penicillin G along diaphragm of the fetus (arrow
indicates hyperechoic location of injected PPG). To view this image in full size go to
the IVIS website at www.ivis.org .
This videoclip depicts the injection of penicillin into the abdominal cavity of an equine
fetus. The fetus is oriented with its head to the right. The ribs are visible as two dotted
lines. The needle is introduced from the top-right corner of the image and penetrates
through the chest and the diaphragm into the abdominal cavity (indicated by the arrow
in Figure 2). Penicillin is injected and accumulates under the diaphragm as a bright
white area that lines the curvature of the diaphragm (indicated by the arrow in Figure
3). - To view this video go to the IVIS website at www.ivis.org .
Figure 4. Injection of procaine penicillin G into the caudal abdomen of an equine fetus
(arrow indicates hyperechoic location of injected PPG). In this case fetal death was not
induced subsequent to the injection and a second injection was necessary to induce
fetal death. To view this image in full size go to the IVIS website at www.ivis.org .
Figure 5. Ultrasonogram of an equine fetus 24 hours after fetal injection. Note the
hyperechoic region in the cranial abdomen of the fetus (arrow). To view this image in
full size go to the IVIS website at www.ivis.org .
Mares that are candidates for transabdominal fetal twin reduction are treated with oral altrenogest (beginning
on the day of the procedure), systemic antibiotics as well as flunixin meglumine for three days. Oral
altrenogest is continued until the recheck examination two weeks after the procedure. The benefits of
supplemental progestin therapy are uncertain, and some authors suggest equal success without the use of
supplemental progestin [7]. If mares are placed on supplemental progestin, it is imperative that periodic
monitoring of fetal viability be conducted to ensure that two dead fetuses are not retained in utero because of
the exogenous progestin therapy - a circumstance that we have observed in one of our clinical cases. Most
pregnancy losses subsequent to this procedure occurred within 2 to 4 weeks after the procedure [7].
Page 4
Outcome
Success rates (measured as viable singleton foals born at term) vary across publications with this technique;
however, success rates of 32-57% have been cited in previous studies [7,10] (Ball unpublished). Although
there are a number of potential reasons for death of both fetuses following the procedure, one likely cause
appears to be related to the frequency of intervascular connections between twin fetuses in the equine. Based
upon the incidence of blood chimerism in equine twins, it appears that 44 to 50% of heterosexual twin
pregnancies in the horse have vascular anastomoses [12,13]. It would seem likely that the presence of vascular
anatomoses at the time of fetal twin reduction would result in death of the adjoining twin fetus due to the
circulation of either the injected solution or other tissue degradation products. Because there is no known
means to identify the presence of these chorionic anastomoses via ultrasonography, there is no method to
identify which twin pregnancies might be susceptible to loss of both fetuses due to shared placental
vasculature.
Anecdotal information regarding the size and vitality of singleton fetuses born after a successful twin
reduction suggests that such fetuses may suffer some in utero growth retardation even after successful twin
reduction by intrafetal injection. Unfortunately, data regarding birth weights of foals born to this procedure is
not available in current literature. Evaluation of the placenta from foals born subsequent to twin reduction,
however, suggests that placental microvillous formation may be sub optimal in that portion of the placenta that
expands after death of one twin fetus [11] (Fig. 6 & Fig. 7). Because placental microvillous formation is
well-established by around Day 150 [14,15], it appears that although the remaining viable fetus may gain an
increased total placental area, the microvillous exchange surface may not be appreciably increased in these
pregnancies [11].
Figure 6. Chorionic surface of the placenta from a singleton foal born subsequent to a
fetal twin reduction at Day 115 of gestation. Note that part of the uterine body and
horn have a very sparse formation of microvilli. To view this image in full size go to
the IVIS website at www.ivis.org .
Figure 7. Close up of normal microvillous chorion (A) and avillous chorion (B) from
the placenta shown in Figure 6. To view this image in full size go to the IVIS website
at www.ivis.org .
The fetus that dies after intrafetal injection becomes mummified and is typically present within an inhoohooted
pouch protruding into the allantoic space of the remaining live fetus at term [11] (Fig. 8). Fetal bones may or
may not be present depending upon the stage of gestation at which fetal death was induced (Fig. 9 & Fig. 10).
Figure 8. Remnant of the placenta from the dead twin fetus is present along the
chorionic surface of the remaining singleton placenta at term as a linear band (arrows).
To view this image in full size go to the IVIS website at www.ivis.org .
Figure 9. Fetal mummy present as an inhoohooted sac in the allantoic cavity of the
remaining normal singleton placenta at term (arrow). To view this image in full size go
to the IVIS website at www.ivis.org .
Figure 10. Radiograph of fetal mummy (Fig 9) showing bones present within the
mummified fetal remnant. To view this image in full size go to the IVIS website at
www.ivis.org .
Page 5
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All rights reserved. This document is available on-line at www.ivis.org. Document No. A0202.0400 .

[bndranch]

maremidwife said:

The twins in question were not "detected" at 6.5 months, but "still there" then.

I will say first hand that I know very little about twinning except it does happen far too often. Sassy was ultra-sounded 6 times and it wasn't until the 6th ultra-sound at 6 1/2 months that the twins were found.
Second of all I had a GOOD friend of mine too ultra-sound her mare for twins at the right time. It was a confirmed singleton pregnancy. However at 7 months the mare went into labor and aborted twin foals. She was devistated and not only that the mare ended up retaining her placenta, getting lamnitis and eventually passed away. This owner did everything she knew of and it was the VETS fault it was not detected.

[toria]

this is my first post, as I have been lurking for a long time....just wanted to say thanks to all who are lending their knowledge on this subject, it is fascinating to read!

[wolfdenfarm]

I will second maremidwife re: Cornell was successfully injecting one fetus to save the other in 1990. Actually, they successfully did it in 1988 with a client's mare - it was "experimental" then. I would imagine it has become much more common and better modified almost twenty years later.

One of my mares had a "bug" of some sort at six months of pregnancy which caused her to go off her feed and spike a temperature. She responded to antibiotics, Banamine, and Bute, but I feared for the baby. When the vet came to palpate, he couldn't feel the foal because at that stage of the pregnancy, it is way up and forward toward the ribcage. I asked about ultrasound and he said that if he couldn't feel the foal, he couldn't ultrasound it. Everything else felt normal (tone, cervix, etc.) and the mare is now nearing her due date. I don't see how the twins were only detected at six months if they are normally out of reach at this point -- unless an ultrasound was done at a University or facility that had a BIG sonogram machine that could do it externally.

I have had twins several times. A few happened back in the late 80's when our vet didn't have an ultrasound machine, and none of them ended well. The most recent twin conceptions I have had, have had one pinched, or the pregnancy aborted. I refuse to put a mare through the stress and resulting tragedy ever again.

When you watch your vet resuscitate a premie twin three times, and then see your vet cry when you lose it, it has a huge impact on your decision making processes after that regarding twins.

[mythicfriesians]

I have a fair bit of experience with foaling, as well as a fair bit of formal taining, and have thankfully never had to deal with twins myself. But I have a friend who has two mares that regularly double ovulate and produce twin pregnancies, so I'll give my insight.

If you find a twin pregnancy early enough - PINCH IT! You are better off aborting both pregnancies than just waiting it out.

Having participated in countless ultrasounds, I can certainly see how any vet, regardless of skill level, could miss a twin pregnancy. Especially if the position of the second embryo is at a bad angle! And if the vet doesn't ultrasound often, then there is an even higher chance. So I think that the chance of a twin pregnancy going undetected is just not that uncommon, and through no fault of the owner. We do depend on our vets for so much, and even the best vet is still human, and therefore, fallible.

The trouble comes with dealing with mares known to be carrying twins past the point where they can be safely pinched.

Yes, aborting the twins at 6 months, or even 8 or 9 months, does carry risk. But the risk is so much more if the mare carries those twins to term. The decision is a very personal one and can only be made by the mare's owner.

If the decision is made to let the mare carry to term, then the owner has to go in knowing the risks and being prepared for them. Many breeders (myself definately included) operate on very tight budgets, and can not afford lengthy vet stays. But the cost of a vet clinic stay, or a c-section, needs to be weighed against the loss of the mare. Because that is the very possible result of a mare trying to give birth to twins.

Some times twin foals are simply unavoidable - we do everything we can to prevent them, but we can only do so much. My biggest worry is simply that people try to beat the odds and intentionally let twin pregnancies continue - please, please don't put any mare through that kind of trauma. It is never worth it.

Allison

[onthedeck]

it was the VETS fault it was not detected.

Time out for a second. Vets are humans too. They make mistakes like all of us do. Don't be so quick to blame the vet entirely. Mistakes happen. When twins are detected, no matter what stage, whatever steps should be taken to ensure that the pregnancy is a singleton. Sometimes that means terminating if it's late term.