FETUS POSITIONS IN UTERUS II FETUS POSITIONS IN UTERUS II. MECHANISM OF LABOUR IN VERTEX PRESENTATION As. Univ. Dr. A.R. Pintilie

Fetus LIE – the relation of the long axis of the fetus to the mother

Fetal ATTITUDE – the posture of the fetus FLEXION DEFLEXION EXTENSION Fetal ATTITUDE – the posture of the fetus

Fetal PRESENTATION - that portion of fetal body that is either foremost within the birth canal or in closest proximity to it. The presenting part can be felt through the dilated cervix only on vaginal examination.

Cephalic presentations Vertex; B. Sinciput C. Brow; D: Face

Frank (extended) breech Complete (full) breech Breech presentations

Shoulder presentation

Fetal POSITION – refers to the relation of an arbitrarily chosen portion of the fetal presenting part ( named DENOMINATOR) to an arbitrarily chosen point from the pelvic inlet. Accordingly, with each presentation there may be 8 positions.

Fetal skull

The pelvis is divided into 8 parts (the arbitrarily chosen points) for the purpose of description

Vertex presentation - denominator - occiput

Sinciput presentation - denominator - bregma

Brow presentation - denominator – (root of the) nose

Facial presentation - denominator – (mentum) or chin

Breech presentation – denominator - sacrum

Shoulder presentation – denominator - acromion

Vertex presentation-positions

Labour mechanism in L.O.A.

Uterine contraction – the only active event of labour

The passive processes of labour – The finish of the shape structure of the lower segment

The passive processes of labour: The dilatation of the cervix The formation of the forewaters

The passive processes of the labour: Labour mechanism in L.O.A. – the cephalic extremity

Mecanismul de naştere – ANGAJAREA

Mechanism of labour in R. O. P Mechanism of labour in R.O.P.-flexion,engagement,internal rotation,descending,extension,expulsion

Mechanism of labour in L.O.A.

The first stage of labour (or stage of dilatation) – lasts from the onset of true labour until the cervix is fully dilated

The second stage of labour (or stage of expulsion of the fetus) – lasts from full dilatation of the cervix until the fetus is born

The third stage of labour – lasts from the birth of the child until the placenta and membranes are delivered and the uterus has retracted firmly to compress the uterine blood sinuses