The female pelvis
The bones of the female pelvis
Pelvis (or pelvic skeleton): a hard ring of bone, which supports and protects the pelvic organs and the contents of the abdominal cavity.
The size and the shape of the pelvis is important for labour and delivery:
narrow pelvis: can make it difficult for the baby to pass through the pelvic canal
normal broad pelvis: easier for baby to pass through the pelvic canal
The pelvic canal
The pelvic canal seen from the side, with the body facing to the left
The pelvic canal is the bony passage through which the baby must pass. It is the canal from the pelvic inlet to the pelvic outlet.
The pelvic inlet is 13cm wide. It is the space where the baby's head enters the pelvis during delivery.
The pelvic outlet is 11cm wide and 12.5cm at its widest dimension from top to bottom. It is the space where the baby's head emerges from the pelvis during delivery.
The baby's head has to rotate to get through the widest part of the pelvic inlet and then get through the widest part of the pelvic outlet.