Page 30 - 33Elctronic Book (3) Normal Labor

Fontanelles:

Areas where sutures meet. They are six in number.
Four fontanelles lie at the anterior & posterior end of the temporal sutures on each
side no obstetric importance.

Anterior Fontanelle or Bregma:
▪ It is large, lozenge shaped.
▪ Formed by the meeting of four bones, two frontal and two parietal bones.

▪ Has a soft membranous floor.
▪ Becomes obliterated 1.5 years after birth.
Posterior Fontanelle:

▪ Small, triangular shaped.
▪ Formed by the meeting of three bones, two parietal bones and the occipital
bone.
▪ Has a bony floor.

▪ It is obliterated at full term.
▪ Membranous in the preterm baby.

➢ NB: The anterior temporal fontanelles are at the junction of the temporal and
coronal sutures. The posterior temporal fontanelles are at the junction of the
temporal and lambdoidal sutures.

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