The cervix is opened by the babyÂs head pushing against it with each contraction. You can visualize this action by picturing the cervix as a turtle neck sweater through which the head is slowly emerging. Ideally, to push the cervix open most effectively, the babyÂs chin is flexed, and the smallest part of the babyÂs head (the occiput) presents first. However, sometimes the babyÂs occiput is facing backwards or is posterior, so it does not emerge first.
Posterior Position
 Occiput Posterior (OP)
 Right Occiput Posterior (ROP)
 Left Occiput Posterior (LOP)
The baby presenting in a posterior position can lead to a host of issues. For one, dilation and progression usually take longer, and some women get Âstuck at a certain point in dilation. The mother may experience intense back pain, since the babyÂs skull is pressed up against her sacrum. She may also experience the urge to urinate during each contraction, because the babyÂs forehead is pushed up against her bladder.
At times it is it difficult to rotate a baby out of the posterior position, especially if the baby has entangled itself in the cord. There are yoga poses that are encouraged and discouraged during the last trimester to help the baby move into the ideal birthing position.
Specific yoga poses to omit from the 3rd trimester practice are:
 Legs up the wall
 Supta Baddha Konasana (at the end of class)
 Supported bridge for a long period of time
It is advisable to do any Âbelly down pose like childÂs pose, cat/cow, body circles and a brief downward facing dog. (Please exclude downward dog if the baby was once in a breech position and has finally turned head down.) I also encourage women to sit on a birth (exercise) ball or sit upright or leaning forward in chairs. If the mother has access to a pool, swimming is a fantastic activity for the last trimester since the mother is belly down for a prolonged period of time, and immersing the body in water can help reduce swelling.
During the last trimester I encourage the mothers to spend as little time on their backs as they can. This includes asking them to check in with the way they recline at home as well as in the yoga studio. It is so easy (and desirable!) to come home and drop back into the couch or comfy chair. They should avoid doing so, however, since it creates a hammock-like shape for the back and invites the baby to settle into a spine-to-back position.
Another reason that the baby may present posteriorly is that the motherÂs uterine ligaments and pelvic floor muscles are tight and somewhat twisted, preventing her baby from settling into a good position. Luckily, many poses we do in prenatal yoga encourage the pelvic and uterine ligaments to gently open and relax. Exercises that relax and tone the pelvic floor muscles are also included in class.
Specific asanas for preparing the pelvis for labor and delivery:
 Baddha Konasana (cobblerÂs pose)
 Supported or unsupported squats
 Upavistha Konasana (wide angle pose)
 Janusirasana (head to knee pose)
 Pigeon pose
 Virasana (heroÂs pose)
If the baby is malpositioned and the mother is aware of what side the baby is laying on, she can help correct this by arranging her body to encourage the baby to shift during savasana or while asleep. If the baby is OP, the mother should use Âpure side lying as opposed to semi-prone. The mother should lie on the side towards which the occiput is already facing, with the babyÂs back toward the bed.
If the mother would prefer to rest in a semi-prone position, she needs to lie on the side in which the babyÂs occiput and back are facing towards the ceiling. For example, if the baby is ROP, the mother would be on her left side in a semi-prone position and on her right side for Âpure side lyingÂ.
Breech Position
 Breech
o Footling breech
o Frank breech
o Complete breech
o Kneeling breech
Another issue some mothers face is the baby being in a breech position. This could mean the baby is standing straight up in the womb (footling breech), presenting butt first (frank breech), sitting cross- legged in the womb (complete breech) or the baby is kneeling inside (kneeling breech). Either way, very few doctors will deliver a breech baby vaginally. If a mother finds out her baby is breech, she is often anxious to help turn the baby around. Luckily, there are some yoga poses that can assist with this.
Poses to help turn a breech baby:
 Prolonged inversion like downward dog
 ÂButt up childÂs pose
 Supported bridge pose
 Right angle handstand at the wall ***advanced practitioners only
 AVOID squatting, as it opens the outlet of the pelvis and invites the baby to wedge itself deeper down.
Beyond these specific yoga poses, acupuncture has been known to help. Also, you can try placing ice at the fundus since the baby will likely move away from the cold. Or, place music or light down at the pelvic opening since babies will go toward sound and light.
In general, mothers should be mindful of the babyÂs position as she nears her due date and tailor her practice accordingly. Yoga can have a powerful effect on these last few weeks and days of pregnancy!