Di Di Twins Switching Sides in the Womb: What To Know

| Reviewed By Sarah Schulze, MSN, APRN, CPNP

If you are currently pregnant with dichorionic/diamniotic twins, also known as di di twins, you are likely feeling a lot of movement in your uterus.

It’s normal to wonder what is going on in there and how that movement is affecting the babies. 

Can di di twins switch sides?

The answer is no. While each baby can change its position throughout the pregnancy, di di pregnancies mean that in most cases each baby has its own amniotic and chorionic sac. This creates barriers that make side switching nearly impossible.

Even without side switching, the position of twins in the womb can change.

Di Di Twin Movement in the Womb

Twins can position themselves in a variety of ways, and the positioning can affect the pregnancy and the birthing process.

Normal Position of Di Di Twins

Babies can change positions in the womb throughout the pregnancy, but it can get more complicated with twins. With less space, they may have a harder time changing positions as the pregnancy progresses.

Di di twins often position themselves vertically in the womb since this arrangement offers more wiggle room for each. The vertical positioning could mean both are head down, both are breech, or one is head down and the other is breech. 

It’s possible for one twin to be vertical while the other is positioned horizontally. The horizontal positioning is called transverse and can make a vaginal delivery unlikely.

Why Di Di Twins Sometimes Switch Places

It is extremely rare for di di twins to switch sides because of the amniotic and chorionic sacs surrounding them. While you may feel the babies move around and change positions, it is highly unlikely they will actually switch from one side to the other.

What is more common is one baby being labeled baby A because he is closer to the cervix and then baby B moving into the lower, closer position. This can happen throughout the pregnancy. 

When Switching Sides is Most Likely to Occur

If di di twins were able to switch sides at all, it would likely be very early. As a twin pregnancy progresses, babies can’t move as freely because they run out of space. 

During the third trimester, your babies will get in position for birth, and these are likely the positions they will remain in for the rest of the pregnancy. However, even this can change. Babies have been known to change positions during labor. 

Is It Harmful for Di Di Twins To Switch Sides?

Due to how rare it is for di di twins to switch sides, it’s not really studied. However, it is essential that doctors know which twin is which as they monitor them in the womb. If there is a problem with one of the twins in utero, doctors need to know so they can make sure that baby gets immediate assistance when born.

Doctors also need to know what position each twin is in during labor. One may be head down and have an easy birth, but the other could be breech or transverse. This can change the birth plan and cause complications for the mom or babies.

Do All Di Di Twins Switch Places at Some Point?

Most di di twins don’t switch places at all. They may rearrange themselves multiple times, but the membrane separating them keeps them from being able to simply move past each other easily.

What To Expect With Di Di Twin Delivery

Expecting the unexpected is a good plan. C-sections are common with twin births, but it is possible to have a vaginal birth if both babies are in the right positions. 

Related Questions 

What Percentage of Di Di Twins Are Identical?

Even though most di di twins are fraternal, between 20-30 percent are identical. This occurs when one egg is fertilized by the same sperm and splits 1-4 days after fertilization. 

How Common Are Di Di Twins?

Di di twins are the most common type, accounting for 70 percent of twin pregnancies.

Your babies will likely move around a lot while in the womb, so your doctor will keep a close eye on them to help you prepare for birth.