Womb Twin Survivors (1) - Signs of a twin
-
Upload
womb-twin-administraor -
Category
Education
-
view
12.651 -
download
3
description
Transcript of Womb Twin Survivors (1) - Signs of a twin
Womb Twin Survivors:
A research project about the sole survivors of a
twin or multiple pregnancy
Headed by Althea Hayton
What is a womb twin survivor?
The sole survivor of a
twin or multiple pregnancy
An ultrasound image of a twin pregnancy. The fetus at the top has died. The fetus below will
survive to be born alone.
What is a womb twin?
In a twin or multiple pregnancy one or more of the embryos or fetuses may die during the pregnancy or
around birth.
A womb twin has a very brief life: sometimes lasting only a few days
or weeks.
Some womb twins manage to survive until birth, but are stillborn.
1 in 10 people is a womb twin survivor
How do we know?
• 1 in 100 births is a twin birth• For every twin birth there are 10 womb twin survivors• That is 10% of the population!
Boklage, C. E. (1990). “Survival probability of human conceptions from fertilization to term." International Journal of Fertility 35(2): 75, 79-80, 81-94.
Are YOU a womb twin survivor?
The signs:
1. In your mother’s pregnancy
2. At your birth
3. In your body
Your mother’s pregnancy
Twinning - a brief introduction
Monozygotic twinning
Identical (monozygotic)twins formed from one zygote
Note: zygote = fertilised egg
Dizygotic twinning
Fraternal (dizygotic) twins formed from two zygotes
Note: zygote = fertilised egg
Multiples
Triplets, quadruplets or more, from three or more zygotes
Womb twin survivors can be:
• Monozygotic (MZ)
• Dizygotic (DZ)
• Multiple
The death of a twin before birth
More images like this: www.layyous.com
Uterus extra large in first trimester
One foetal heart stops beating
The “vanishing” twin on the ultrasound scan
The sac on the left is all that remains of the second twin
Bleeding in the first trimester
1 in 5 pregnant women experience first trimester bleeding and the pregnancy proceeds normally.
This can be a sign that one twin has died.
Trimester = 12 weeks
Ovulation stimulating hormones
Clomiphrene citrate is used to assist conception by stimulating the ovaries. This which causes hyperovulation, which often leads to twinning and the birth of twins.
Hyper-ovulation = the production of more than one egg a month by the ovaries
More than one embryo implanted after IVF
After in-vitro fertilization and the re-introduction of several embryos back into the womb, it is not unusual for more than one embryo to implant and begin to grow. In many cases, one or more of these will die after a few
days or weeks.
Embryo = an un-born child less than 12 weeks from conception
Miscarriage, but pregnancy continues normally
When a mother miscarries her baby, and the fetus is completely expelled with a lot of bleeding, it looks as if the pregnancy is over - but sometimes she remains pregnant and a baby is born after all: in that case, she had been carrying twins.
Abortion, but pregnancy continues
A miscarriage is induced but the pregnancy continues, leading to one live birth. This is not a “failed” abortion because the mother had been carrying twins: rather, it is a
partial abortion.
Multi-fetal pregnancy reduction
The number of fetuses in a multiple pregnancy is reduced by selective abortion of one or more of them. The survivor is born alone, along with the shrivelled remains of the others.
Quads or more may be reduced to triplets; triplets to twins, or twins to one baby.
At birth
One twin stillborn
One twin may die in the process of being born, or may have already died in the womb before the time of birth.
The birth of an acardiac twin
One twin may not develop vital organs, such as a heart (acardiac) kidneys or a proper skeleton. The mis-shaped body of the twin will be delivered along with the sole survivor. The body may be attached to the survivor’s placenta or delivered separately. An ultrasound image
of twins, one of them acardiac.
A fetus papyraceousThe fetus papyraceous is the name given to the tiny body of a dead twin, whose body remains in the womb attached to the placenta of the sole survivor. It may be embedded in the placenta and scarcely visible. In this case it is clearly seen, but a fetus papyraceous can be missed if the placenta is not carefully examined after
delivery.
Body of the dead twin
Placenta after delivery
Additional cords or sacs
When the placenta is examined after delivery, an additional umbilical cord, with or without an empty sac, or may be seen. This cord or sac belonged to a twin, who died in the first 10 weeks of life. This was before the skeleton was formed so the body disintegrated and was soon resorbed.
Resorb = to remove cells, a tissue or structure by gradual breakdown into the component materials and disperse into the circulation
In the body of the sole survivor
Parasitic twin
Illustration of an adult man with a parasitic twin from “Monstrorum Historia Memorabilis” by Johann Schenk, 1609
A parasitic twin is formed when a zygote split into a monozygotic twin pair more than 14 days after conception. One twin remains attached to the other. If the parasitic twin is surgically removed, then the individual becomes a half-twin: a womb twin survivor.
The fetus in fetu
If a parasitic twin develops within the body of the other, this is known as a fetus in fetu. At birth, or many years later, the parastic fetus may cause problems, and is surgically removed. After removal, the surviving twin is alone - a womb twin
survivor.
Fetus in fetu = a fetus inside a fetus
TeratomaA teratoma is formed when a parasitic twn begins to develop with the body of the other, but only some tissues form properly. In this example the outer membranes have been removed to reveal, a few teeth, some fatty tissue and a piece
of bone.
Dermoid cyst
Inside the cyst
When a parasitic twin develops inside the other twin, the result is a dermoid cyst. Within it there are no recognisable tissues. In this example there is some hair to be seen. Dermoid cysts can be found anywhere in the body, often on one of the ovaries. In this example the cyst is visible just under the skin, on the jaw.
Signs of the opposite sex
A man
A woman
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
When a dizygotic, opposite-sex twin dies before birth, an additional dose of hormones passes into the body of the DZ
womb twin survivor.
Cerebral palsy
Pharoah, P. O. and Y. Dundar (2009). "Monozygotic twinning, cerebral palsy and congenital anomalies." Hum Reprod Update 15(6): 639-48.
The incidence of cerebral palsy and some other congenital abnormalities has been strongly associated with the loss of a monozygotic twin in the first few weeks of life.
Left-handedness
Left-handedness has been associated with the loss of a monozygotic “mirror” twin early in life.
“Mirror” twins are monozygotic twins who are like mirror images of each other, one left-handed, one right handed.
If you have none of these signs…
But you feel sure you are a womb twin survivor, you still could be. The loss of
a twin before birth often goes undetected by everyone involved.
There is help available….
Womb Twin Survivors
Find out more
http://www.wombtwinsurvivors.com
http://WombTwinSurvivors.blogspot.com