What Is a Multiple Pregnancy?
A pregnancy is considered a multiple pregnancy when there is more than one baby growing in the womb. Twins, triplets, quadruplets, and so on all fall under this category.
A multiple pregnancy occurs in two ways.
From One Egg
The first is when the fertilized egg splits itself during early development, resulting in two or more identical but separate individuals. Doctors and scientists call this monozygotic since these babies all came from the same egg.
Because they come from the same egg, their DNA is completely identical. This means that they will look the same and they will all have the same gender. That’s why twins or more are called identical siblings.
From Different Eggs
The second way is when there are two or more eggs fertilized in the same pregnancy. Unlike their monozygotic counterparts, these babies come from completely separate eggs. They only share half of the same genes. This means that while they may look similar physically, they are not totally the same. This also means that these babies may have different genders. As opposed to identical siblings, we call these babies fraternal siblings. Nowadays, multiple births with fraternal siblings are more common because of a number of factors.
Factors for Multiple Pregnancy
Here are some factors that increase the likelihood of multiple pregnancy.
Fraternal siblings is a hereditary trait. If you have a twin, or there are twins in your family, it is more likely for you to give birth to fraternal siblings. In the same vein, if you have a history of giving birth to fraternal siblings, then it is more likely for you to have a multiple pregnancy again.
Women who are older than 35 are more likely to release two or more eggs during a single menstrual cycle compared to younger women.