Malpresentation and Malposition

Malpresentation refers to any fetal presenting part other than vertex (cephalic with a well-flexed head), including breech (see above), transverse or oblique lie, brow presentation, and face presentation.

Malposition refers to an abnormal position of a cephalic presenting part relative to the maternal pelvis, most commonly occipito-posterior (OP) position, where the fetal occiput points toward the maternal sacrum rather than the pubic symphysis.

Transverse or oblique lie: fundal height and abdominal shape are atypical, with no presenting part palpable in the pelvis and the fetal poles palpable in the flanks
Occipito-posterior position: often associated with a longer, more painful labor with significant back pain ("back labor"), and a higher likelihood of instrumental delivery or cesarean
Brow presentation (partial extension of the fetal head): generally incompatible with vaginal delivery of a term-sized fetus given the larger presenting diameter
Face presentation (full extension of the fetal head): vaginal delivery may be possible if mento-anterior, but mento-posterior face presentation is generally undeliverable vaginally

Transverse or persistent oblique lie at term: admission is generally advised from around 37 to 38 weeks given the risk of cord prolapse with spontaneous rupture of membranes; stabilizing induction (attempting to correct the lie under controlled conditions with immediate access to cesarean) may be considered, but persistent unstable lie or transverse lie in labor requires cesarean section
Occipito-posterior position: many rotate spontaneously to occipito-anterior during labor; persistent OP position causing delay may be managed with maternal positioning (hands and knees, forward-leaning positions), oxytocin augmentation if contractions are inadequate, or instrumental delivery (rotational forceps or ventouse) or cesarean if vaginal delivery is not achieved
Brow presentation: generally requires cesarean unless it converts to either full flexion (vertex) or full extension (face) during labor
Face presentation, mento-anterior: vaginal delivery may proceed with careful monitoring; mento-posterior face presentation generally requires cesarean, since further extension (which would be needed for descent) is not anatomically possible

Referral: obstetric-led care for any confirmed malpresentation or malposition in labor; senior obstetric review for any suspected transverse lie, brow, or face presentation.

Clinical toolsCalculators

BMI GCS EDD Parkland Formula

Corrected Sodium Corrected Calcium Anion Gap Creatinine Clearance Insulin Calculations qSOFA Wells PE Wells DVT CHA₂DS₂-VASc HAS-BLED CURB-65 Centor/McIsaac

Labour Dystocia

Dystocia is the broader clinical term encompassing abnormal, difficult, or prolonged labor from any cause, of which prolonged labor and obstructed labor (see those entries) represent points along a spectrum of increasing severity.

The term is often used clinically to describe difficult progress attributable to the "three Ps": power (uterine contraction inadequacy), passenger (fetal size, presentation, position, or, rarely, anomaly), and passage (bony pelvis or soft tissue).

Systematic assessment of each of the three Ps in turn: palpation and, where available, intrauterine pressure catheter assessment of contraction adequacy; vaginal examination for fetal position, station, and degree of molding/caput; and clinical assessment of pelvic capacity, alongside consideration of estimated fetal size.

Partograph monitoring, as detailed in the Prolonged Labour entry, remains the primary tool for identifying dystocia in real time.

Management follows directly from identifying which of the three Ps is the dominant contributor, as detailed in the Prolonged Labour entry: oxytocin augmentation for a power problem with confirmed inadequate contractions, positional changes and, where appropriate, instrumental delivery or cesarean for a passenger problem (malposition, macrosomia), and cesarean section for a genuine passage problem where vaginal delivery is not achievable
Adequate analgesia, hydration, and emotional support throughout, given the physical and psychological toll of prolonged, difficult labor
Careful reassessment at defined intervals rather than open-ended augmentation, to avoid delaying necessary escalation to cesarean where true disproportion exists
Vigilance for progression to obstructed labor (see that entry) if dystocia is not appropriately managed

Referral: obstetric-led care throughout, with senior review triggered by partograph action line crossing or failure to respond to initial corrective measures.

Malpresentation and Malposition

Overview

Clinical Features

Diagnosis

Management

Overview

Clinical Features

Diagnosis

Management