Vertical Birth

While the awareness about the dangers and disadvantages of giving birth while lying on one's back is more widespread, this is still the main position that the majority of women in the US give birth.

The disadvantages of pushing while lying on the back include:

• Pelvic outlet is reduced, which creates less room for baby
• Less urge for the mother to push
• Baby takes longer to descend - the "curve of Carus" along the sacrum and tailbone when on the back makes more of an uphill route that baby needs to maneuver before emerging under the pubic bone
• Less oxygen to the baby due to increased pressure from the weight of the uterus and baby on the mother's inferior vena cava (artery)
• More difficult for mother to reach down and assist in the birth of her baby
• Increased pain for mother
• Uterus has to work harder to create contractions to bring baby down
• Contractions may slow or stop
• Increased risk of further aggravating or creating new hemorrhoids
• Greater risk of perineal tears and lacerations
• Easier for care provider to perform an episiotomy
• Increased insecurity on the part of the mother, as she cannot as easily see what is being "done" to her
• Greater risk of shoulder dystocia (where the shoulder becomes lodged behind the pubic bone) because of the decreased pelvic outlet

The advantages of pushing while upright and/or squatting include:

• Squatting increases the pelvic outlet, thereby creating more room for a larger baby or baby with a presentation issue (posterior, asynclitic, etc)
• Gravity helps baby to descend
• The force of the uterus during pushing is helped by being upright - gravity assists in the uterus being able to contract and tilt forward
• Baby is better able to present naturally in the mother's pelvis, and rotates into more favorable positions if needed while the mother is upright
• Less pain is felt by the mother as the baby descends past the sacrum due to the fact that there is no pressure (by a bed) on this part of her body
• Perineal tissues stretch more effectively, often reducing the need for postpartum repairs and/or discomfort
• Mother is able to help assist in the delivery of her baby, as well as see her own baby being born
• Sacrum is much more flexible and moves with descent of baby's head
• Mother is able to maintain eye contact with care providers (if she desires) and there are no surprises in touch

Even semi-sitting or semi-reclining positions interfere with natural, spontaneous pushing stages. In both the semi-sitting and semi-reclining positions, the sacrum is compressed, thereby reducing the diameter of the pelvic outlet.