Vanishing Twin: Why it Happens and Why You’re Not to Blame

Vanishing Twin: Why it Happens and Why You’re Not to Blame

Learning you are suffering from vanishing twin can be devastating. It should be noted that this can happen in higher-order multiples (triplets, quads, etc.) as well. It is important that you know that this diagnosis is rare. There is nothing you could have done to prevent this from happening in your pregnancy. 

Let go over what this condition is, what it isn’t and how it could happen in twin pregnancies.

What is vanishing twin syndrome?

Vanishing twin syndrome happens during twin pregnancies when a woman is carrying twins and then suddenly is only carrying a singleton. This can happen in twin pregnancies, triplet pregnancies, or more. The name is actually pretty self-explanatory.  One of the twins, triplets or more just vanishes. There is no logical explanation for why it happens.

You MUST have confirmed twin pregnancy in order to suffer from this heartbreaking diagnosis. Meaning, a feeling you might have been carrying twins is not sufficient to classify your singleton pregnancy a result of this rare condition.  Further, a fetal death only counts as a vanishing twin when the fetus vanishes. The loss of a twin in utero alone is not the same thing.

This syndrome is one of many concerns that singleton pregnancy doesn’t come with. 

twin pregnancy timeline week by week

If you just heard that second heartbeat for the first time, or you know it’s been two for a while, you need to read our twin pregnancy week by week timeline to help you learn what happens week by week with twins. Click here to learn more… and while you’re at it, check out our expecting twins classes and twin parent coaching services.

Are there any symptoms to watch for?

While the only way to know if you are suffering this type of loss is through an ultrasound, there are a few symptoms that you should report to your doctor for closer examination. If you notice a sudden decrease in hCG levels which would be detected in a blood test, your provider might want to follow up with an ultrasound or Doppler. If you experience bleeding, uterine cramps, a sudden decrease in pregnancy symptoms, or pelvic pain you should contact your provider. Remember that none of these symptoms is a definitive problem and you should not worry until your doctor tells you to worry. There are plenty of more common reasons for any of these symptoms that do not result in this type of loss.

What causes vanishing twin?

One explanation as to how vanishing triplet syndrome could happen would be if one embryo stopped growing but was still in the womb along with the developing embryos. This would then cause vanishing triplet syndrome. Another explanation could be that one or more of the fetuses are absorbed by the other, usually earlier in the pregnancy. There is no justifiable reason for why it happens – it truly does happen without rhyme or reason.

Many times vanishing twin can be most closely compared to a spontaneous miscarriage of only one embryo. Spontaneous miscarriage is often caused by unknown chromosomal complications. That may provide little in the way of comfort except for the knowledge that you didn’t cause this, nor could you have prevented it.

a pregnant woman holding her belly in black pants and a black crop top. Vanishing twin photo

Possible consequences of vanishing twin syndrome

The most obvious consequence of this condition is on the mothers’ mental health. Self-care will be critical in dealing with feelings of sadness, guilt, and anger in the months following the diagnosis.

Vanishing twin presents a unique feeling of guilt during pregnancy. After a miscarriage, the typical feelings of sadness and anger are often made more complicated by feelings of relief and excitement for the arrival of the surviving twin. Knowing how to hold both of those realities at the same time isn’t something anyone can be prepared for. It is absolutely vital that mothers who are dealing with this news find support. Expecting moms should surround themselves with those who will honor their grief while holding space for the happiness of the new baby. 

How is it different than a parasitic twin?

Parasitic twin is different in a few ways. With parasitic twin, two embryos begin to develop but never fully separate. One twin spontaneously stops developing and the tissue will be born attached to the dominant twin. This type of twinning is incredibly rare and only occurs in identical twins. 

This is different than the vanishing twins in the sense that this twin is not absorbed into the mother’s body and may actually cause problems for the surviving twin. The parasitic twin cannot survive on its own, as it is not fully developed and the strain of “carrying” said parasitic twin may actually cause severe and serious health problems for the viable twin. 

a pair of hands holding a pregnancy test

Vanishing twin and future fertility

There is little research to suggest a connection between this diagnosis and infertility. If you are having fertility issues, whether you have suffered a loss or not, you should consult with your doctor to see if there might be an underlying cause.

Handling vanishing twin syndrome

Vanishing twin is nothing to be ashamed of, and it’s not something you did wrong. You didn’t do anything that caused this to happen in your twin pregnancy. Sometimes it just happens. If you have experienced vanishing twin in the past or are currently experiencing it, talk to your doctor about any concerns you may have about your chances for future pregnancies and children. If you are having trouble getting pregnant again or carrying a baby to term, talk with your doctor about it.

It is also very important that you find someone to talk to about your loss. Make no mistake, this is a devestating loss for an expecting mom. It may help to find a therapist or another mother who has suffered from a similar loss to help you deal with your feelings.

woman in a crop top holding her pregnant belly outside in a field

How vanishing twins impact future fertility

There is little research on the effects of vanishing twin on future fertility. In short, there doesn’t seem to be much in the way of connection. If you are struggling to conceive or carry a baby to term following a twin pregnancy that resulted in vanishing twin syndrome, it won’t hurt to mention it to your doctor. Many times, the level of concern will depend on the reason for your loss.

Vanishing twin causes many emotional issues and, if you have suffered from any fetal loss in the past, it is important that you find someone to talk about your feelings with. Again, it may help to find a therapist or another mother who has suffered from vanishing twin as well. Be sure that you are taking care of yourself and getting the support you need in order to move on while honoring your loss. Stress can be a difficult barrier to conception in some cases so it is necessary to deal with your grief. 

This syndrome can be hard for mothers, during their pregnancies and after, so it’s important to make sure that you are taking care of yourself. You are feeling a loss. It may help to find someone to talk about your feelings with. Start with your significant other or a family member. Also, consider joining a support group where others understand what you are going through.

Treatment options for vanishing twins

This type of loss often happens during the first trimester. In the first trimester of your pregnancy, there is no treatment required. Your pregnancy will continue on as if you were always carrying a singleton.  Most often, in these cases, the fetus will be absorbed into the placenta and the unaffected baby will grow normally.

In the case of a later loss, close monitoring and ultrasounds may be recommended to keep an eye on the remaining fetus and ensure their growth and development is unaltered. Some studies suggest that there may be a slightly increased risk for low birth weight and/or preterm birth for the remaining baby. But the data is far from definitive on this, so it’s best not to worry much about it.

There is also an increased risk of cerebral palsy on the surviving twin in the case of a loss later in the pregnancy. The good news is that there is only about a 3% chance of losing a twin after your 20th week. Another twin pregnancy milestone to look forward to!

twin pregnancy week by week emails

Want to get weekly emails about your twin pregnancy? Sign up for the Twiniversity email list! Subscribe today to get emails about giveaways, events, weekly article roundups, and more! We’ll be sending you a weekly twin pregnancy email to keep you on track with your pregnancy to-do list! Click here to learn more… and while you’re at it, check out our expecting twins classes and personal twin parent coaching services.

Ways to prevent vanishing twins from happening in future pregnancies

Unfortunately, there isn’t much you can do to prevent vanishing twin in your pregnancy. It’s always best to eat and sleep well. There is no proven scientific evidence that proves what is or is not a risk factor. That means it’s not possible to say whether or not anything might cause vanishing twin or make it more likely for this to occur in your twin pregnancy.

What we do know is that proper medical care is the first step to avoiding many pregnancy complications. It is important for all pregnant women to find an obgyn that they trust to manage their medical care. 

The effects on fertility and how you can prevent it in future pregnancies

If you are experiencing trouble getting pregnant or carrying your baby to term you may want to talk with your doctor. If applicable you may mention vanishing twin and how it could affect future pregnancies. It is important that you are taking care of yourself during this time and finding support from those around you who understand what vanishing twin is like.

Vanishing twin is a rare phenomenon that can happen for many reasons, and it’s important to understand the effects vanishing twin has on fertility. If you worry about vanishing twin, it may be of some comfort to know that taking care of yourself is the best you can offer.

Most often, the vanishing twin is a result of chromosomal abnormalities that would likely make the fetus unviable in the best of circumstances. Hold space for your grief while experiencing joy over the birth of your surviving twin. We hope that our post sheds some light on this baffling condition. Our goal is to alleviate fears about what vanishing twin syndrome could mean for families!