Malposition of the fetal head Flashcards
Malposition of the fetal head
Definitions
- Presentation – the leading body part
- Denominator – the prominent part of the presenting part.
- Position – the relationship and orientation of the denominator of fetus to the maternal pelvis.
- Lie – longitudinal, oblique and transverse axis in relation to axis of maternal uterus
- Malposition – any position in the vertex head presentation that is not occipitoanterior.
a. Occipitoanterior (OA) – normal position (90% of cases)
b. Occipitoposterior (OP) – occiput face the sacrum.
c. Occipitotransverse (OT) – occiput faces lateral part of the pelvis oblique orientation).
- Asynclitism – sagittal suture is in the transverse diameter of the pelvic inlet (not in line with the birth canal.
Occipitoposterior position
- Diagnosis
a. Vaginal examination – palpitation of sagittal suture and posterior fontanelle posterior to pelvis
- Management
a. Spontaneous resolution – head rotates anteriorly
b. In case of persistent OP
i. Evaluation of cervical dilatation, effacement and head engagement
ii. If well-established labor delivery can be made (assisted delivery can be done)
iii. If slow labor progression and no other contra-indication → oxytocin infusion, pain relief and rotational forceps or vacuum maneuver.
iv. If cervix is not dilated completely then C-section
Deep transverse arrest
- Definition: when the anterior rotation fails resulting in large presenting diameters.
- Diagnosis – vaginal examination in prolonged second stage with fully dilated cervix
- Management
a. C-section
b. Assisted delivery – only when the head has engaged and easy rotational maneuver is possible
Deep transverse arrest
- Definition: when the anterior rotation fails resulting in large presenting diameters.
- Diagnosis – vaginal examination in prolonged second stage with fully dilated cervix
- Management
a. C-section
b. Assisted delivery – only when the head has engaged and easy rotational maneuver is possible
