At the beginning of the labour, your baby usually lies facing towards your right, or left, side. This can be in either a lateral, anterior or posterior position, depending on which way their back is lying. The most common positions for a baby to lie in, just before labour starts, are the right or left anterior or lateral positions, with right and left posterior positions being less common. You may wish to read more in
posterior position.
Image 4-07 shows the baby in a left anterior position.
Image 5-25 shows the baby in a right anterior position.
Image 4-06 shows the baby in a left posterior position.
Image 5-26 shows the baby in a right posterior position.
Image 5-27 shows the baby in a left lateral position.
Image 5-28 shows the baby in a right lateral position.
As the baby descends down the pelvis, their back begins to rotate gradually towards the woman's front. At the same time, the baby flexes their head, to bring their chin to rest on their chest. This makes the crown of the baby's head lead the way, with the baby's head beginning to mould to the shape of the woman's body.