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Womb Twin Survivors

A 'womb twin survivor' is typically the sole survivor of a twin or multiple conception. It can happen in 3 different ways:


1. In the simplest case, conception results in 2 co-twins in the womb: 1 dies in the pregnancy but 1 reaches birth. At birth, the sole survivor of such prenatal loss can be described as a 'womb twin': created with a co-twin in the womb, but born without it.


2. Another (perhaps less common) way in which a person can become a womb twin is if they were part of a multiple set - of 3 or more embryos. If even one of those embryos should die, the remaining co-twins that go on to be born will each be a womb twin. That is to say, each surviving co-twin would have had a bond with that one co-twin in the womb that died - that didn't make it from womb life into born life. 


So, you might be a child or adult with a living twin sibling - or even be part of a living triplet or quadruplet set - and yet you may still be a 'womb twin' if there was a co-twin lost during the pregnancy. In other words, a person can have a living co-twin and yet still have lost a co-twin in utero as well.  Just because you are part of a living twin-pair or multiple set doesn't mean there was no prenatal co-twin loss for you.

3. The third case - most common in IVF pregnancies - is where a person is conceived as part of a multiple pregnancy (3 or more fertilised embryos) and sadly none of their co-twins make it to be born. Once born, we describe that person as a 'womb twin' because they had co-twins in the womb that are missing in daily life. Uniquely, the person would have multiple prenatal imprints: of each lost twin. We discuss this key point in more detail in our workshops and trainings on prenatal co-twin loss. 



You might have seen the term Twinless twin. A twinless twin is a person who has lost their co-twin or co-twins after they were born, not during pregnancy. There is a difference, then, between a twinless twin and a womb twin (though of course we can learn a lot about the impact of prenatal twin loss by understanding twinless twins). If you want to learn more about support for twinless twins, please see our resources pages (e.g. for links to the Twinless Twins Support Group International TTSGI, and the Lone Twin Network).   Our website, here, is dedicated to each and every Womb Twin.

A term you will hear, particularly in many European countries, is Alone Born Twin. It means exactly the same thing as 'womb twin' (for which there is no direct translation in many European languages). So, when you see the term 'alone born twin', think of it in exactly the same way as you think of 'womb twin'. They are not describing two different things, but simply reflect the different structures of European languages.

You will also sometimes see specific reference to Twin and Multiple twin loss. Note that, as described above, a 'womb twin' can be the result of the prenatal loss of 1 co-twin, 2 co-twins, 3 co-twins, or more. The term 'womb twin' does not imply there were only two embryos conceived. It just means at least 1 co-twin was lost in utero.


It is relevant that, Twinning is a medical term used to describe any type of twinned conception (of 2, 3, or more embryos). To put it simply, then, a Womb Twin is the survivor or any twinned pregnancy in which co-twin loss took place, of any kind.


Although not strictly relevant to this point on terminology, it is interesting to note that multiples are usually a 'pair and spare' or 'pair and pair' configuration - it is rare for an embryo to split directly into 3+ units. So, most multiples are also actually twins! It is very helpful to know if you were part of a multiple set, because, if you were, you have 'imprints' of a bond not only with each co-twin but also with the set as a whole. In general, our view at Womb Twin is that it is surprisingly common for people to find multiple prenatal co-twin loss imprints - it could be the most common loss type. 

Imprints of prenatal co-twin loss are the starting point of a lifelong journey into what happened to you in utero and how it affects you now. If you are a womb twin, a hidden Prenatal Imprint of a lost co-twin (with which you were created) may still be exerting emotional, relational and spiritual effects on you. Womb Twin research has shown that a womb twin will tend to experience a similar specific range of lifelong aftereffects due to their early, profound, formative losses. We've studied the imprints.

To learn more about this from Althea Hayton, who coined the term and wrote the first scholarly texts on the topic (with contributions from world leading twin experts, scholars, therapists, and womb twins themselves), please refer to Althea's books, in particular Untwinned (2007), Womb Twin Survivors (2011), and Healing Path (2012). 


Vanishing Twin pregnancy

At the Third International Congress on Twin Studies, held in Jerusalem in 1980, prenatal twin loss was discussed and the term 'vanishing twins' was coined to describe it. A vanishing twin pregnancy soon became the accepted medical term to describe a particular situation: when a pregnant woman is scanned by ultrasound, two sacs are seen at the first scan but one sac has "vanished" from view by the next scan and in the end only one baby is born. The term 'vanishing' is an objective description from the perspective of a scan. However, in truth these unborn babies do not vanish they die. A surviving co-twin somehow 'knows' this deep loss, close to their very core.  


The enclosed twin is a less commonly discussed phenomenon. A dermoid cyst, a teratoma, or a fetus in fetu can be considered examples of an enclosed twin. In the case of a 'fetus in fetu', it can be clearly seen that the body of a twin is trying to develop. The teratoma isn't too difficult to see as a partially developed twin either. However, we know less about dermoid cysts and how they are related to this topic. There are very few medical references. But people keep sending us their stories .....


A stillborn twin

In it not uncommon for a person to know they are a womb twin because they lost  their co-twin at or close to the time of birth. In such a situation, people know for sure they are a womb twin even if was no ultrasound scan (such as before the 1980s). The loss of a co-twin at birth is a profound loss and leaves a powerful perinatal imprint on any surviving co-twin/s. 

Of course, a death at birth is always traumatic for parents. We know this very well. And twin pregnancies are also increasingly part of lengthy, stressful and costly fertility treatments, making the anguish doubly painful. Parents can discover early on that they are expecting twins (or more) and get to know each co-twin as a distinct being. After a loss at birth, the realities of caring for one surviving co-twin can make it hard for the parents to go through a normal grief process in a healthy way, together. This is, of course, especially true if one or both parents happens to be a womb twin too! 


The story of the prenatal loss of one of more co-twins is fascinating. It has personal, relational, intergenerational and societal implications we all need to take seriously. 



A twin pregnancy of about 10 weeks. The lower sac contains a live fetus but the fetus in the upper sac has died. The sense of Something or Someone being there for a while but now

gone missing, will remain

somewhere in the back of the mind of the sole survivor - the womb twin survivor.

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