The fetal skull consists of 3 main parts - the vault, face, and base/brow. The vault contains 2 frontal bones, 2 parietal bones, 1 occipital bone, and 2 temporal bones, separated by sutures including the frontal, coronal, sagittal, and lambdoid sutures. There are 6 fontanelles but the 2 important ones in obstetrics are the anterior and posterior fontanelles. Understanding the diameters, landmarks, and molding process of the fetal skull is important for midwives to evaluate labor progression and fetal well-being.

1. fetal skull
ms. Yashasvi kashiv
msc nursing 1st year

2. Introduction
the fetal head is large in relation to the fetal body
compared with the adult .
adaptation between the fetal skull and the pelvis is
necessary to pass through the pelvic during labour with
complication .

4. Objectives..
The objectives are
1. To Fetal skull molding is
important for adaption of fetal head the
birth canal during vagina delivery.

6. FETALPARTS.
The fetal skull consist of 3 major part…they are
 Vault – it is a quadrangular area bounded anteriorly by the bregma and
coronal sutures behind by the lambda and lambdoid suture and laterally
by lines passing through the parietal eminence. It is the commonest
presentation.
 Face –it is an area bonded on one side by the root of the nose and the
supra –orbital ridges and on other by junction of the floor of mouth with
neck. It is composed of 14 small bone that are also firmly united and not
compressed.
 Base/brow- It is an area bounded on one side by the anterior fontanelle
and the coronal suture and on the other side by the root of the nose and

8. BONEOF THEVAULT
The bone of the vault.
Vault is consist of –
 2 frontal bone
 2parietal bone
 1 occipital bone
 2 temporal bone
2 frontal bone It separated by the frontal suture .it forms the forehead to sinciput. The
ossification centre of bone is the frontal eminence. The frontal bone fuse into a single
bone by age 8 years of age.

9. CUNT….
2 parietal bone –
Which lie on either side of skull and occupy most of the skull .the
ossification centre of each of these bones is called the parietal eminences
.two parietal bone separated by sagittal suture.
1 occipital bone
Which forms the back of the skull and the part of its bone.
The part of it contribution to the base of the skull as it contains the
foramen magnum, which protects the spinal card as it leave the skull.
The ossification centre is the occipital protuberance.

10. CUNT…
The occipital bone separated by the lambdoidal suture from the
parietal bone , while the coronal suture separated the frontal
form the parietal bone .Each of the two parietal bone is
separated from the temporal bone on each side by the temporal
suture.
2 temporal bone –
On both side of head forms part of the vault.

11. SUTURE
A suture is a type of fibrous joint that is only found in the skull. Fibrous joint are
connected by dense connective tissue, consisting mainly of collagen.
There are 4 suture in fetal skull….
 Frontal suture –it is also called metopic. It located between two frontal bone is
called frontal suture.
 Coronal suture –It located between 2 parietal and 2 frontal bone on either side.
 Sagittal suture- It is also called longitudinal .It located between parietal bone. It
divided the skull in two left and right halves.
 Lambdoid suture- It located between two parietal bone and the occipital bone.

14. FONTANELLES…
A fontanelle is a space created by joining of two or more suture.
Wide gap in the suture line is called fontanelle. In this many fontanelle {6 in
number} but in obstetrical only two fontanelle are important. they are
Anterior fontanelle
Posterior fontanelle
 Anterior fontanelle- It is also called bregma. It is a diamond in shape membrane.
Filled space located between the two frontal and two parietal bone of the
developing fetal skull. It closes approximately at 18 to 24 month after birth. Its
antroposterior and transverse diameters measure approximately 3.4cm in length
and 2.3cm in width.

15. CUNT….
It became pathological, if it fails to close even after 24 month.
 Posterior fontanelle- It is also called lambda. It is a triangle
shape .it lies at junction between the sagittal suture. It close
approximately at 6 to 12 weeks .and diameter is 1.2cm in length
and 1.2cm in width.

17. Regionof fetal skull

22. DIAMETERSOF SKULL
Anterior posterior longitudinal diameters-
 Suboccipito bregmatic-It measure nape of the neck {occipital protuberance} to the centre
of the bregma.
Diameter -9.5cm
Attitude –head is complete flexion.
Presentation- vertex
 Suboccipito frontal-it is measure from the nape of the neck to the anterior end of the
anterior fontanelle or centre of the sinciput.
Diameter -10cm
Attitude –incomplete flexion
Presentation-vertex

23. CUNT…
 Occipital frontal-it measure from the occipital protuberance to the glabella.
Diameter -11.5cm
Attitude – head extend
Presentation-vertex
 Mentovertical- it measure from the point of the chin to the highest on the
vertex.
Diameter -13.5cm
Attitude –partial extension
Presentation –brow

24. CUNT…
 Submento vertical – it measure from the point where the chin joint the neck to the
highest point on the vertex. {Sagittal suture}.
Diameter -11.5cm
Attitude –incomplete flexion
Presentation –face
 Submento bregmatic-it measure from point where the chin join the neck to the
centre of the bregma.
Diameter -9.5cm
Attitude –head complete extend.

25. CUNT…
TRANSEVERSE DIAMETER –
 Biporital diameter- it extent between two parietal eminence.
Diameter -9.5cm
 Supra sub parietal- it extent the parietal eminence to below the opposite
eminence.
Diameter -8.5cm
 Bitemporal diameter –the diameter between the two furthest point of the
coronal suture at the temples.
Diameter -8cm
 Bimastiod diameter –it located between the tips of the mastoid processes.
Diameter -7.5cm

26. Landmarks…
 Occiput – it is the occipital bone {back of the head}.the part below the
occipital protuberance [landmark] is known as sub occipital region.
 Sinciput – it is the forehead region of frontal head.
 Parietal eminence- it is the eminence of parietal bone on either side.
 Frontal eminence – it is the eminence of frontal bone on either side.
 Occipital eminence – it is the eminence of the occipital bone.
 Mentam- it is the chin.
 Vertical points-it is the centre of the sagittal suture.

27. Cunt..
 Frontal points – it is the root of the nose.
 Sub occiput – it is the junction of fetal neck and occiput.
 Sub mentum-it is the junction between the neck and chin.
 Biparietal –it is the transverse distance between two parietal
eminences.
 Bi temporal- it is the distance between two lower and of the
coronal suture.

28. Conclusion…
It is important for midwife learn about fetal skull by
knowing the landmarks will enable them to estimate the
program of labour.
Midwife also can evaluate diameter of the
fetal skull and fontenelle and sutures

29. Bibliography..
 Marshall j .& Raynor M[2004] Myles textbook for midwife 16th edition London ;
Elsevier.
 Verrals S. [2015]. Anatomy and physiology applied to obstetrics 3rd edition
Singapore ; Elsevier.
 Winson N.V & McDonald S.2014 Illustrated dictionary of midwifery Edinburgh ;
Elsevier.