The Vanishing Twins Syndrome: Causes and Effects​



Several years ago, I had read somewhere that most singleton pregnancies start out as multiple pregnancies, and that often made me wonder at the number of twins, triplets or even quads, walking around who didn’t know they had started their lives with some other living beings. Even their mothers don’t even know they had one time carried more than one baby in some cases.

The Vanishing Twin Syndrome is what this phenomenon is called, and it is said to be a lot common than it is thought. However, it might not have been detected as often as it is now, due to the fact that science back in the day was not as advanced as it is now.

I remember the story a doctor-friend told me, about this syndrome. He had mentioned one of his patients, who had gone through that experience. The woman involved had come in for her first scan, and they had seen three gestational sacs and poles. When she had been told she was carrying triplets, she had been thrilled and anxious; pleased because she was having multiples and anxious because this child was supposed to be a last child, having had two other children already. Having three more bodies to cater for wasn’t exactly her plan.

For whatever reasons why the Vanishing Twin Syndrome happens, her subsequent ultrasound scans showed one baby less, and while she was still dealing with her new-found disappointment at losing her baby, another scan showed one of the babies had also vanished, leaving just one baby.

By this time, the doctors were more concerned about ensuring that the sole baby living was developing normally, and that its vanishing twins hadn’t fused into it, to avoid a case of the parasitic twin.

Anyways, that woman went on to have a healthy pregnancy with her now singleton but I’m not sure she would ever get over the fact that her last pregnancy had started out as a multiple one, only to end just as she had wanted in the beginning; a singleton.

According to my research, the Vanishing Twin Syndrome was conventionally recognized in 1945, and it occurs when a twin or multiple disappears in the uterus during pregnancy, as a result of a miscarriage of one twin or multiple. The fetal tissue is then absorbed by the other twin, multiple, placenta or the mother. This gives the appearance of a “vanishing twin.”

Estimates indicate that vanishing twin syndrome occurs in 21-30% of multifetal pregnancies.


061715_molarpregnancy_thumb_large-1Even though there are no known causes of the vanishing twin syndrome, there are some pointers that can give an idea of what causes this.

According to my doctor-friend, the Vanishing Twin Syndrome could be nature’s way of ensuring that abnormalities are not perpetuated. It sounds much the same way some miscarriages are caused by chromosomal irregularities. Medical practitioners have also concluded that most vanishing twins are fraternal twins, rather than identical. Due to the fact that if they were identical twins, then they were likely to have same genetical make up, and if one aborted, then they both did.

In fact, this tendency for an embryo to go AWOL is one reason that some doctors transfer several embryos at once during In Vitro Fertilization. If five embryos are put into the uterus, they hope that one or two would survive. Some embryos will fail to implant, but for the others, doctors factor in the reality of vanishing twins.

Apart from that, one likely reason is age. Researchers report more cases of Vanishing Twin Syndrome in women older than 30, though that may be due to the fact that older mothers in general have higher rates of multiple pregnancies, especially with the use of fertility treatments. Symptoms usually begin early in the first trimester and include bleeding, uterine cramps, and pelvic pain.

The other cause of the Vanishing Twin Syndrome is improper cord implantation, which in itself is a worrying condition, as it affects the baby and the mother too. He placement of the umbilical cord determines how the baby will be born, even whether it is going to be a live birth or a stillbirth. Truth!



what-is-vanishing-twin-syndromeThe good news is that when the Vanishing Twin Syndrome occurs in the first trimester, the mother usually goes on to experience a normal pregnancy and delivers the single healthy baby without complication or intervention.

In the much less likely case that a twin dies in the second or third trimester, the remaining baby may be at an increased risk of intrauterine growth restriction and the mother may be at risk of preterm labour, infection or haemorrhaging.

When one of the foetuses dies after the embryonic period, i.e. after eight weeks, then the fluid in the twin’s tissues, the placental tissues, and the amniotic fluid gets reabsorbed. This results in the disappearance of the dead twin and this does not cause any pressure to the surviving foetus. During delivery, the deceased foetus is identified as fetus papyraceous, i.e. flattened dead twin through loss of fluid and the soft tissue.

Low birth weight; it has been reported that approximately 1/3rd of the pregnant mothers who were diagnosed with this syndrome gave birth to low birth weight infants.

In other cases, the surviving baby takes on some of the lost twin’s cells and becomes a chimera – one person with two sets of DNA.

In the end, it does not matter if the loss happened in the first or third trimester; what matters is the fact that the new parents-t0-be know that they were having more than one baby, as they might feel an awkward combination of grief over the loss of one baby and relief for the viability of the surviving baby.

Whatever happens, kindly allow yourself and your partner to grieve. Remember to acknowledge the loss of your child and the loss of your identity as parents of multiples, and to also celebrate the life of your surviving twin.

Baby dust to you all!



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  1. Hi Nicole and Kemi.. Pls I need all the articles I can get on sperm issues..I have gone through the blog and still need some answers maybe. Hubs result came back with zero sperm count. I need you to break it down pls.. are there drugs that can restore or whatever happened,we are to see a Urologist. But I just want to know what we may be facing in the days ahead.Kindly help a sister as I am new to it all

    • So sorry about your hubby’s diagnosis, hun. I’ll have a look for all articles we have. But to be honest, while there are some meds/foods that can boost sperm count, in cases of azoospermia, the odds of this happening are low. Has your Urologist discussed possible surgical means of sperm extraction? This is possible and a few of our members have conceived this way.

  2. Hi Nicole. Compliments of the season. So with hubs, varicocele was diagnosed. We will be seeing the Urologist again and I have been told once it is corrected all will be well. I am holding on to faith while letting God do the impossible through medicine. Can u tell what u know pls and if women have gone on to conceive after their hubs got treatment


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