Basic principles Flashcards
Define: Lie Presentation Denominator Attitude Syncliticism Station
Lie: long axis of fetus relative to long axis of mother
Presentation: fetal part that is lowest in birth canal
Denominator: portion of presenting part used to define position in relation to maternal pelvis
Position: relationship of denominator of presenting part to maternal pelvis
Attitude: relationship of the fetal head to the fetal spine
Syncliticism: degree of lateral flexion of the head
Station: measure of descent; bony part of fetus relative to the ischial spines
Checklist for leopold information?
- which fetal pole is occupying the fundus?
- which side is the fetal back?
- which fetal part is occupying the lower uterine pole?
- if cephalic, is head flexed or extended?
What are the mechanisms/cardinal movements of labor?
1) Engagement
2) Descent
3) Flexion
4) Internal rotation
5) Extension
6) external rotation/restitution
7) explusion
What are the 3 plains of clinical pelvimetry? How are they defined?
Inlet: sacral promontory, symphysis pubis, linea terminalis; measured by obstetrical conjugate (diagonal conjugate 1-2 cm)
Mid-pelvis: hollow of sacrum, ischial spines, sacrospinous ligaments
Outlet: coccyx, intra-pubic angle, inter tuberous diameter
What are the 4 pelvic types; how are they defined? (Caldwell-Moloy classification, 1939)
anterior/posterior triangles based off ischial tuberosities
Gynecoid- classic female (50%; A & P triangles are the same; best prognosis for vaginal delivery)
Anthropoid - 30% (AP diameter > transverse diameter; favors OP or 1st stage arrest of labor)
Android- 15% (posterior sagittal much shorter than anterior sagittal - heart shaped; poor prognosis for vaiginal delivery - 1st stage arrest)
Platypelloid 5% (very wide TV diameter, short AP diameter; favors OT position)
What are the preferred sizes of the planes of pelvimetry?
AP/oblique/transverse
Inlet: 10/11/12 cm
Midpelvis: 11/11/11 cm
Outlet: 12/11/10 cm
