Why might babies be malpositioned?
Sometimes the gorgeous design for fetal positioning is tampered with by cultural habits (slouching on the couch), poor nutrition (low iodine), or even the mistaken habits of the health practitioner or other helper (over use of epidural, esp. before 5 cm dilation).
What is malposition?
We women are designed for birth. Babies are designed for birth. during labor, babies who are in a vertical, curled position descend through the pelvis in a tube-shape. If a baby can't fit because of position, that's a "malposition."
The baby is oblique when baby's head is in the mother's hip. The baby's body and head are diagonal, not vertical and not horizontal (transverse lie). This is fine for a second twin. But oblique is not an optimal fetal position for a singleton baby after 30 weeks gestation.
Right Occiput Posterior
Baby is head down and the back is to the side- The right side. This position can be deceptively reassuring. ROP is the most common of the four posterior positions.
The ROP baby has the forehead in the front, lined up with the symphysis pubis and bladder. Little baby hands are likely to wiggle on both sides of the center line (linea nigra) just above the pubic bone area, but below the mother's navel.
Will Baby fit?
Is it CPD or not?
Head size is less important when it comes to fitting through the pelvis than is the angle of the baby's head. A posterior baby will present a bigger head circumference and can sometimes get stuck in a pelvis that the same baby could have fit through if anterior. See what to do to reduce incorrect diagnosis of CephaloPelvic Disproportion.
Head down is not enough!
Many parents think that as long as the baby is head down in the womb the baby is ready for birth. Head down is only half the story.
It is a big relief to find out the baby is not breech (buttocks coming through the pelvis before the head is born). Especially when so many breech babies are born by cesarean these days. But being head down is only the first step.
For the best chance at a natural birth,
- Baby should have his or her chin tucked.
- For a first time mother, the baby is expected to engage in the pelvic brim (dip into the pelvis a bit) by 38 weeks.
- A second baby or more, may wait above the brim until labor begins (see Open the Brim if baby isn't engaged by active labor).
- And finally, baby's back is to the mother's left (or directly in front) with baby's feet in the right. (Why not on the right or the front on the right side?)
Asynclitism means asymmetrical. Its when a baby’s head is tipped towards one shoulder. The tipped head has a harder time passing through the narrow part of the pelvis; the ishial spines. Labor becomes longer, and sometimes baby doesn't fit out the pelvis...Happily, we have techniques for this problem.
Occiput Posterior - OP
In this article, what is a posterior fetal position, pregnancy clues a mother can use to tell if baby is posterior, why it matters in labor, who might have an easy posterior labor and who might need more help. Click to go to What to do in a Posterior Labor.
Pregnancy may or may not show symptoms - labor may or may not be significantly effected. When labor IS effected, there is a range of what can happen.
“Baby, stay anterior!"
What is "the most practical way of making sure my baby stays anterior? I've had TWO posterior babies! UGH!”
Mainly, the baby will "stay" anterior if your womb is balanced (symmetrical, not torqued or twisted) and you continue to use good maternal positioning. Positioning without releasing tension in the abdominal soft tissues and pelvic joints isn't likely to succeed in rotating a baby in pregnancy, especially for a woman with a history of posterior babies or breech, because these positions show the uterine ligaments weren't in balance before pregnancy.
Myths of occiput posterior
There are some myths about laboring with a posterior baby.
Let's start with appreciation for Penny Simkin's brave confrontation of a dogmatic trend that has arisen over the last few years. At first, I was rather surprised to hear a talk by Penny Simkin called, "The OP Fetus; How little we know." Now, the light has gone on. Parents and professionals alike have some misunderstandings about the influence of posterior presentation on labor. For instance, "She didn't have back labor so I didn't think the baby was posterior." Or, "We did everything we could because we tried hands and knees position in labor."
Sometimes a midwife or doctor will say they don't pay much attention to a head down baby's position in late pregnancy because some posterior babies come out fine. Emphasis mine. Spinning Babies is about the 15-30% that need more help than strong labor and the hands and knees position.
Transverse; lying sideways
“Transverse Lie” means a sideways position. The baby has his head to one of his mother’s sides and the bottom across her abdomen at her other side. This is normal before, and at, 26 weeks, but by 29-30 weeks we expect babies to be head down, or at least breech. If not, this article outlines what to do, easy ways to fix it, and what to do if they don't - read the stories, too.
The word transverse is also used in phrases describing two head down positions: Left occiput transverse (an ideal starting position) and right occiput transverse. These head down positions means baby is facing mother's hip.
Left Occiput Anterior
The left occiput anterior position is often the easiest fetal position for the start of labor.
Babies settle in the LOA position naturally when the womb is pretty well balanced. This position helps the baby be in the smallest diameter to fit the pelvis.
Click "Read LOA" to see pictures and understand more.
Right Occiput Anterior
The ROA baby is not on the Spinning Babies list of clearly ideal or optimal fetal positions. Read why not...
Dip in the Belly
"There is an indentation in my belly near my navel. Does this mean my baby is posterior?"
An indentation, or dip, near or beneath your belly button can mean a couple of things. One possibility is that the baby is posterior. The posterior baby has his or her back along the mother's back. The knees are bent and the arms are bent, usually. This makes the baby in the shape of a letter "C." The opening of the "C" is towards the mother's abdomen wall and navel. The opening can allow a "dip" in the mother's belly shape, right about the place her navel is.
What is the effect of an anterior placenta on fetal positioning?
An anterior placenta means that the placenta is located on the front of the uterus. Most of the baby will be hidden behind it.
It is a common belief that the anterior placement of the placenta causes the baby to be posterior. The fact that this is sometimes true doesn't mean it is always true. Babies can be anterior with an anterior placenta. Abdominal tone, when loosened, can allow the baby to turn away from the placenta and face the mother's back.
Chin tucking to engage
Flexion into the brim of pelvis helps the baby fit through the pelvis. Flexion refers to the tucking of the baby’s chin, often the first step to engagement of the head and the start of labor.
Flexion, or chin tucking, is more important than starting labor with an anterior head position!
Many posterior babies can be born with natural labor, or just a bit of Pitocin, when they begin active labor with their heads tucked. Learn about both flexion and engagement here.
Occiput Transverse (OT or OL)