Chapter 8 : Fetus in utero
**Fetal Lie, Presentation, and Attitude:**
- **Lie:** Refers to the relationship of the long axis of the fetus to the long axis of the maternal spine or centralized
uterus. Most common is longitudinal (99.5%), followed by transverse or oblique.
- **Presentation:** Part of the fetus at the lower pole of the uterus. Cephalic (head) presentation is most common
(96.5%), followed by podalic (3%) or shoulder (0.5%). Compound presentation occurs when more than one part
presents.
- **Presenting Part:** Part of the presentation overlying the internal os and felt through the cervical opening. In
cephalic presentation, it can be vertex, brow, or face, depending on head flexion. In breech presentation, it can be
flexed, extended, or footling.
- **Attitude:** Relation of fetal parts to each other, usually in flexion. Exceptions include extension of the head or
legs, which may affect the course of labor.
**Denominator and Position:**
- **Denominator:** Arbitrary bony point on the presenting part relating to quadrants of the maternal pelvis.
Examples include occiput in vertex presentation and sacrum in breech.
- **Position:** Relation of the denominator to different quadrants of the pelvis, divided into segments. Positions are
described as anterior, posterior, right, or left, with common vertex positions like LOA and ROA.
**Causes of Longitudinal Lie and Cephalic Presentation:**
- Longitudinal lie is favored by the ovoid shape of the uterus and fetus. Cephalic presentation predominates due to
gravity (head being heavier) and adaptation (smaller head circumference compared to breech).
**Methods of Obstetrical Examination:**
**Abdominal Examination:**
- **Preliminaries:** Obtain verbal consent, ensure bladder evacuation, position patient in dorsal position with thighs
slightly flexed.
- **Inspection:** Note uterine ovoid shape, contour, enlargement, skin condition, and any abdominal scars.
- **Palpation:**
- **Height of the uterus:** Centralize uterus, assess height by placing ulnar border of left hand on fundus.
- Conditions where uterus height may not correspond to amenorrhea period: twins, polyhydramnios, pelvic tumors,
hydatidiform mole, concealed hemorrhage, mistaken LMP, scanty liquor amnii, fetal growth retardation, intrauterine
fetal death.
**Fetal Lie, Presentation, and Attitude:**
- **Lie:** Refers to the relationship of the long axis of the fetus to the long axis of the maternal spine or centralized
uterus. Most common is longitudinal (99.5%), followed by transverse or oblique.
- **Presentation:** Part of the fetus at the lower pole of the uterus. Cephalic (head) presentation is most common
(96.5%), followed by podalic (3%) or shoulder (0.5%). Compound presentation occurs when more than one part
presents.
- **Presenting Part:** Part of the presentation overlying the internal os and felt through the cervical opening. In
cephalic presentation, it can be vertex, brow, or face, depending on head flexion. In breech presentation, it can be
flexed, extended, or footling.
- **Attitude:** Relation of fetal parts to each other, usually in flexion. Exceptions include extension of the head or
legs, which may affect the course of labor.
**Denominator and Position:**
- **Denominator:** Arbitrary bony point on the presenting part relating to quadrants of the maternal pelvis.
Examples include occiput in vertex presentation and sacrum in breech.
- **Position:** Relation of the denominator to different quadrants of the pelvis, divided into segments. Positions are
described as anterior, posterior, right, or left, with common vertex positions like LOA and ROA.
**Causes of Longitudinal Lie and Cephalic Presentation:**
- Longitudinal lie is favored by the ovoid shape of the uterus and fetus. Cephalic presentation predominates due to
gravity (head being heavier) and adaptation (smaller head circumference compared to breech).
**Methods of Obstetrical Examination:**
**Abdominal Examination:**
- **Preliminaries:** Obtain verbal consent, ensure bladder evacuation, position patient in dorsal position with thighs
slightly flexed.
- **Inspection:** Note uterine ovoid shape, contour, enlargement, skin condition, and any abdominal scars.
- **Palpation:**
- **Height of the uterus:** Centralize uterus, assess height by placing ulnar border of left hand on fundus.
- Conditions where uterus height may not correspond to amenorrhea period: twins, polyhydramnios, pelvic tumors,
hydatidiform mole, concealed hemorrhage, mistaken LMP, scanty liquor amnii, fetal growth retardation, intrauterine
fetal death.