The fetal part that emerges first (or would emerge first) is termed the presenting part.
|
Presenting Part |
Defining Part |
Designator |
|
vertex (top of head) |
occiput |
O |
|
parietal |
|
|
|
brow |
forehead (frontalis) |
F |
|
face |
chin (mentum) |
M |
|
shoulder |
|
|
|
buttocks (breech) |
|
|
|
compound |
one or more extremities |
|
Buttocks (breech)
(a) complete (legs at the level of buttocks)
(b) frank (legs extended with feet near head)
(c) incomplete or footling (with on an extended leg)
Clock with 12 o'clock pubis, 3 o'clock left (L) side, 6 o'clock sacrum, 9 o'clock right (R) side
|
O'Clock Position of Defining Part |
Designation (with "x" the part designator) |
|
12 to 2 |
LxA |
|
2 to 4 |
LxT |
|
4 to 6 |
LxP |
|
6 to 8 |
RxP |
|
8 to 10 |
RxT |
|
10 to 12 |
RxA |
where:
• A = anterior
• T = transverse
• P = posterior
Specialty: Obstetrics & Gynecology
ICD-10: ,
