SECTION 3: FETAL LIE, FETAL PRESENTATION AND FETAL POSITION

1. Fetal Lie

Fetal lie means the relationship between the longitudinal axis of the uterus and longitudinal axis of the fetus. If these Two axes are parallel this is called a longitudinal lie （99.75%）, when the fetal axis is horizontal, it is called a transverse lie（0.25%）and when the fetal axis is oblique in relation to the longitudinal axis this is called an oblique lie. These are usually transient positions and can turn to a longitudinal lie when the patient gets into labor.

2. Fetal Presentation

Fetal presentation denotes the part of the fetus which enters the pelvis first. Cephalic presentation and breech presentation can be seen in a longitudinal lie and shoulder presentation in transverse lie.

Compound presentation are s infrequent: here more than one part of the fetus presents: combinations include head-and hand, head-and foot, buttocks-and hand, buttocks- and foot.

Presenting Part: is defined as the part of the presentation which overlies the internal os and is felt by the examining finger through the cervical opening. In cephalic presentation, the presenting part may be vertex （commonest）, brow or face, depending upon the degree of flexion of the head.

3. Fetal position

Denominator: is an arbitrary fixed point on the presenting part which comes in relation with the various quadrants of the maternal pelvis.

Position: is the relation of the denominator to the different quadrants of the pelvis

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