A twin pregnancy offers unique challenges, and one of them is lack of space in the womb. This can affect how much twins can move around and how long they can change positions.
How late can twins flip?
Twins can flip or change positions throughout the pregnancy. In fact, the second twin may actually flip into a different position once the first twin is out of the womb. While it is common for twins to get in their final positions at around 28 weeks and stay that way, it’s never too late for one or both of them to flip.
The position of your twins can impact the pregnancy, the birth, and their safety while growing. That’s why it’s important to know everything you can about positioning in the womb.
Twin Position in Uterus
Twins can start in a variety of positions and move throughout the pregnancy. However, there are some positions that are more common for twins to be in than others.
Normal Positioning of Twins
The majority of twins position themselves vertically. This allows them room on their side of the womb.
Ideally, both twins will make their way into a head down position, but this isn’t always the case. One twin may be vertically positioned head down while the other is vertically positioned breech. Both can also be breech.
It’s less common for one twin to be vertical while the other is in a transverse position. Transverse means one twin is positioned horizontally. Both twins can also position themselves horizontally.
Why Twins Switch Places in the Womb
It’s not common for di di or mo di twins to completely switch places in the womb. However, they can change positions frequently. This can happen as each one tries to get more room or find a more comfortable position to settle in.
Is It Dangerous for Twins To Change Sides?
Most types of twins can’t change sides. Di di twins have their own amniotic and chorionic sacs, and that makes completely trading places nearly impossible. Even mo di twins have a membrane that separates them and makes switching places difficult.
Mo mo twins face unique challenges in the womb because they do share a chorionic and amniotic sac. That means they can switch sides. In the process, their umbilical cords can become entangled. This can lead to a variety of complications, and that’s why mo mo pregnancies are monitored closely.
How Late Can Twins Change Positions?
Twins can change positions during labor. While they run out of room as the pregnancy progresses, twins can still flip into different positions during the third trimester and beyond.
The twins most likely to fully switch sides are mo mo twins because there is no membrane separating them. This is more likely to happen in early pregnancy when both babies can move around easily.
Mo mo pregnancies are carefully monitored, and mom may be under constant fetal monitoring during the third trimester. If the babies attempt to switch places late in the pregnancy and chance hurting each other in the process, doctors will go ahead and take them via C-section.
How Late Can Breech Babies Flip?
Breech babies can flip to a head down position throughout the pregnancy, though it may become more difficult as time passes. If one twin is breech, your doctor may recommend an external cephalic version, also known as an ECV, to try to flip him. This is not recommended in every situation and usually won’t be attempted until at least 36 weeks.
It’s important to remember that twins can flip during labor. This can be great if a breech baby turns head down, but it can cause problems if a baby who was head down decides to flip into a breech position.
Most Common Presentation in Twin Pregnancy
The most common presentation in a twin pregnancy is both babies vertical and head down. This is called vertex. Both babies in a vertex position gives you the best chance at a vaginal delivery.
Twin Position During Labor
The position your twins are in will determine the plan for birth. Even with a plan going in, things can change when labor starts.
Both babies in a vertex position means their heads are down and they are in a vertical position. This is the best position for a vaginal delivery.
One twin may be head down while the other is feet down. If this is the presentation going into labor, you will need to talk to your doctor about the best option. While a vaginal birth is possible if baby A is vertex, some doctors recommend a C-section since one baby is breech.
However, other doctors might try to turn the breech baby once their twin is out of the womb. Some doctors will also attempt breech deliveries if just one twin is breech.
It’s also possible for the vertex twin to be delivered vaginally and the breech twin to be taken by C-section if he won’t or can’t turn.
If both babies are feet down, you will likely have a C-section. Most doctors don’t want to try a vaginal delivery with twins if baby A is not vertex. It can also be difficult to turn both babies since they won’t have much room towards the end of the pregnancy.
If baby A is vertex but baby B is transverse, your doctor may attempt a vaginal delivery with baby A and then attempt to flip baby B. If that doesn’t work, baby B will have to be delivered by C-section.
This position will require a C-section.
When both babies are horizontal, a C-section will likely be planned.
Do Twins Interact in the Womb?
A study in 2010 found that twins do interact in the womb. In fact, during the second trimester, they are aware of each other and spend more time finding ways to focus attention on each other than anything else.
Do Twins Fight in the Womb?
Babies kick in the womb, and twins are no exception. This can seem like fighting since there is less room to move in the womb during a twin pregnancy and they hit each other.
Amniotic fluid protects the babies from doing any real damage to each other when limbs are flailing, and it’s unclear if the kicking and punching truly constitute fighting.
It’s important to know what position your twins are in so the best decision can be made about birthing choices. Things can change quickly, so prepare for the unexpected.