By Shannon Harlow
Just to reiterate from Part 1 of this series, the first question dealt with ensuring you know the number of babies you’re carrying. It’s important to try to discover early on whether you’re carrying a singleton, twins or high order multiples. Each additional child in utero brings with it the chances for earlier deliveries and increased risks for complications. In addition, the preparation alone for multiples may bring its fair share of frustrations and budgeting so the more time you can give yourself to prepare, the better. Once you’ve gained that information, now it’s time to get on to some other important facts to know about your multiple pregnancy.
Question #2: Can you tell if the babies are in the same sac?
The amniotic sac is your baby’s home along with the amniotic fluid that surrounds him/her. The amniotic sac provides protection while allowing babies the space to move around. The actual sac consists of two membranes known as the amnion and the chorion. Your multiples can share this space or be housed separately within the walls of your uterus.
Most monozygotic (identical multiples that develop from an original fertilized ovum) multiples are enclosed within a shared chorion (the outer layer) with a separate amnion space. A small percentage of identical twins, termed as monochorionic and monoamniotic twins (I’ve often heard referred to as mono-mono or mo-mo twins) share a single amniotic space and chorion which could present additional complications that you and your doctor should discuss. Fraternal multiples, however, will always be encased in separate amniotic spaces because they formed from completely different eggs. These twins are usually called Monochorionic-Diamniotic meaning they share two separate sacs covered by one singular sac, or they can be Dichorionic-Diamniotic meaning they each have their own amnion and chorion.