No matter what way you spin it, it’s not easy to get a baby through the birth canal. It’s just a tight fit. And worse, babies have arms and legs that you have to contend with – they’re not exactly streamlined. Of course, some positions are worse than others in terms of aerodynamics. What are the different types of fetal presentation and what do they mean for your delivery?
The position in which your baby develops is called the “fetal presentation.” During most of your pregnancy, the baby will be curled up in a ball – that’s why we call it the “fetal position.” The baby might flip around over the course of development, which is why you can sometimes feel a foot poking into your side or an elbow prodding your bellybutton. As you get closer to delivery, the baby will change positions and move lower in your uterus in preparation. Over the last part of your pregnancy, your doctor or medical care provider will monitor the baby’s position to keep an eye out for any potential problems.
In the occiput anterior position, the baby is pointed headfirst toward the birth canal and is facing down – toward your back. This is the easiest possible position for delivery because it allows the crown of the baby’s head to pass through first, followed by the shoulders and the rest of the body. The crown of the head is the narrowest part, so it can lead the way for the rest of the head.
The baby’s head will move slowly downward as you get closer to delivery until it “engages” with your pelvis. At that point, the baby’s head will fit snugly and won’t be able to wobble around. That’s exactly where you want to be just before labor. The occiput anterior position causes the least stress on your little one and the easiest labor for you.
In the occiput posterior position, the baby is pointed headfirst toward the birth canal but is facing upward, toward your stomach. This can trap the baby’s head under your pubic bone, making it harder to get out through the birth canal. In most cases, a baby in the occiput posterior position will either turn around naturally during the course of labor or your doctor or midwife may help it along manually or with forceps.
In a transverse position, the baby is sideways across the birth canal rather than head- or feet-first. It’s rare for a baby to stay in this position all the way up to delivery, but your doctor may attempt to gently push on your abdomen until the baby is in a more favorable fetal presentation. If you go into labor while the baby is in a transverse position, your medical care provider will likely recommend a c-section to avoid stressing or injuring the baby.
If the baby’s legs or buttocks are leading the way instead of the head, it’s called a breech presentation. It’s much harder to deliver in this position – the baby’s limbs are unlikely to line up all in the right direction and the birth canal likely won’t be stretched enough to allow the head to pass. Breech presentation used to be extremely dangerous for mothers and children both, and it’s still not easy, but medical intervention can help.
Sometimes, the baby will turn around and you’ll be able to deliver vaginally. Most healthcare providers, however, recommend a cesarean section for all breech babies because of the risks of serious injury to both mother and child in a breech vaginal delivery.
A complete breech position refers to the baby being upside down for delivery – feet first and head up. The baby’s legs are folded up and the feet are near the buttocks.
In a frank breech position, the baby’s legs are extended and the baby’s buttocks are closest to the birth canal. This is the most common breech presentation.
Changing Fetal Presentation
By late in your pregnancy, your baby can already move around – you’re probably feeling those kicks! Unfortunately, your little one doesn’t necessarily know how to aim for the birth canal. If the baby isn’t in the occiput anterior position by about 32 weeks, your doctor or midwife will typically recommend trying adjust the fetal presentation. They’ll use monitors to keep an eye on the baby and watch for signs of stress as they push and lift on your belly to coax your little one into the right spot. Your doctor may also advise you to try certain exercises at home to encourage the baby to move into the proper position. For example, getting on your hands and knees for a few minutes every day can help bring the baby around. You can also put cushions on your chairs to make sure your hips are always elevated, which can help move things into the right place. It’s important to start working on the proper fetal position early, as it becomes much harder to adjust after about 37 weeks when there’s less room to move around.
In many cases, the baby will eventually line up properly before delivery. Sometimes, however, the baby is still in the wrong spot by the time you go into labor. Your doctor or midwife may be able to move the baby during labor using forceps or ventouse. If that’s not possible, it’s generally safer for you and the baby if you deliver by c-section.