What are Monoamniotic Twins anyway?

Do you want to know what a monoamniotic twin is? I have written an article so you can see.

What is a Momo twin?

Many people do not know how to define a Monoamniotic twin. Monoamniotic twins “describes twins that are monochorionic and monoamniotic, that is, there is a single chorion and a single amniotic sac. The amniotic sac is the bag of waters that contains the fetus, while the chorion is the outer membrane. These are monozygotic twins that develop from a single egg/sperm combination which splits into two. When the split is delayed, usually a week or so after conception, the process of growing a placenta, chorion and amniotic sac has already begun, and the two embryos will develop within a single, shared sac. Only about 1% of twin pregnancies will occur in this manner.”( Fierro,2013, p.1)  

Monoamniotic twins share the same sac in their mothers stomach, and they develop from a single egg that splits in two. They not only share the same sac, but there is no dividing membrane between them.  They are swimming in the same space, attached to cords that can wrap around each other. That means that they can cut off each other’s blood supply and

compress each other’s umbilical cords. This makes their survival rate drop to about 50%.  Monoamniotic twins are one of the most rare occurrences in twin pregnancies.  It’s one step away from being conjoined twins.