Vanishing Twin Syndrome (VTS) occurs when one or many fetuses disappears from the womb during early pregnancy, usually resulting in a normal singleton pregnancy.

What are the ramifications for the surviving twin?

There is a great deal of speculation about the psychological and emotional impact of Vanishing Twin Syndrome. Due to a deep longing for some undefined, missing part of themselves (it seems no mate can quite fulfill), single twins (survivors) may experience problems with:

.... relationships and/or even with their sexual identity

.... often suffer from unreasonable feelings of responsibility or guilt

.... may experience troubling, recurring dreams of their twin

.... fear of sleeping alone

.... fears of sudden loss or abandonment

.... profound loneliness

.... eating disorders

....“hearing voices”

.... extreme emotional sensitivity

.... even schizophrenia or multiple personality disorder

Many Vanishing Twin Survivors are left-handed. Personally, based on my experience, I am now saying any left-handed person is most likely a VTS.

If they are not aware that they are twin survivors, they have no context in which to place these very confusing emotions. If the survivor is aware of what happened, the trauma can be processed and overcome, sometimes quite rapidly.

What really happens?

One of the fetuses in a twin pregnancy spontaneously aborts, usually during the first trimester; the fetal tissue is absorbed by the other twin, the placenta, or the mother, thus giving the appearance that the twin "vanished." My experience with VTS is that there can be twins, triplets, quadruplets, etc.

How often does it happen?

Scientists have confirmed that the number of twin conceptions greatly outnumbers the number of actual twin births. Some estimates offer that 1 in 8 people started life as a twin, while in reality only 1 in 70 actually are a twin. In "Having Twins," author Elizabeth Noble claims that 80% of twin pregnancies result in the loss of one or both babies. Other studies predict that Vanishing Twin Syndrome occurs in 21 - 30% of all multiple pregnancies in the United States. It is estimated that Vanishing Twin Syndrome will play a role in 50% of assisted ovulation pregnancies. Why is it happening more frequently?

Although it would seem that incidences of Vanishing Twin Syndrome are increasing with alarming frequency, it is simply that the detection of the phenomenon has increased. Advancements in ultrasound technology allow modern doctors (and parents) the exciting opportunity to peek into the womb. As more doctors routinely use ultrasound in the first trimester, more multiple pregnancies are identified. And a certain percentage of those will be affected by Vanishing Twin Syndrome. In the past, many women experienced VTS without ever knowing it. What causes it?

Just as there is no clear attributable cause for most miscarriages, there aren't always reasons or explanations for the loss of a fetus in a multiple pregnancy.

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