face presentation mechanism of labour

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INTRODUCTION

Diagnosis and management of face and brow presentations will be reviewed here. Other cephalic malpresentations are discussed separately. (See "Occiput posterior position" and "Occiput transverse position" .)

Prevalence  —  Face and brow presentation are uncommon. Their prevalences compared with other types of malpresentations are shown below [ 1-9 ]:

● Occiput posterior – 1/19 deliveries

● Breech – 1/33 deliveries

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Face Presentation

It is a cephalic presentation in which the head is completely extended.

About 1:300 labours.

• It is less common.
• It occurs during pregnancy.
• Anencephaly: due to absence of the bony vault of the skull and the scalp while the facial portion is normal.
• Loops of the cord around the neck.
• Tumours of the foetal neck e.g. congenital goitre.
• Hypertonicity of the extensor muscles of the neck.
• Dolicocephaly: long antero-posterior diameter of the head, so as the breadth is less than 4/5 of the length.
• Dead or premature foetus.
• Idiopathic.
• It is more common. 
• It occurs during labour.
• Contracted pelvis particularly flat pelvis which allows descent of the bitemporal but not the biparietal diameter leads to extension of the head.
• Pendulous abdomen or marked lateral obliquity of the uterus.
• Further deflexion of brow or occipito - posterior positions.
• Other causes of malpresentations as polyhydramnios and placenta praevia.
• Right mento-posterior (RMP).           
• Left mento-posterior (LMP).
• Left mento-anterior (LMA).
• Right mento-anterior (RMA), are the more common positions.
• Right mento-transverse (lateral), left mento-transverse, direct mento-posterior and direct mento-anterior are rare and usually transient positions.

The first position (RMP) corresponds to the first normal position (LOA) as the back should be to the left and anterior in the first position. Mento-anterior are more common than mento-posterior as most cases arise from more deflexion of the head in occipito-posterior position usually in flat contracted pelvis.

During pregnancy (difficult)

• The back is difficult to feel.
• The limbs are felt more prominent in mento-anterior position.
• The chin may be felt on the same side of the limbs as a horseshoe-shaped rim in mento-anterior position.
• In mento-posterior, a groove may be felt between the occiput and the back particularly after rupture of the membranes.
• Second pelvic grip: the occiput is at a higher level than the sinciput.
• The FHS are heard below the umbilicus through the foetal chest wall in mento-anterior position.
• Ultrasound or X-ray: confirms the diagnosis and may identify associated foetal anomalies as anencephaly.

During labour

Vaginal examination shows the following identifying features for face:

• supra-orbital ridges,
• the malar processes,
• the nose (rubbery and saddle shaped),
• the mouth with hard areolar ridges.

Late in labour, the face becomes oedematous (tumefaction) so it can be misdiagnosed as a buttock (breech presentation) where the two cheeks are mistaken with buttocks and the mouth with anus and the malar processes with the ischial tuberosities. The following points can differentiate in-between:

Mechanism of Labour

Mento-anterior position

• Engagement by submento-bregmatic diameter 9.5 cm.
• Increased extension.
• Internal rotation of chin 1/8 circle anteriorly.
• Flexion: is the movement by which the head is delivered in mento-anterior position when the submental region hinges below the symphysis. The vulva is much distended by the submento-vertical diameter 11.5 cm.
• Restitution.
• External rotation.

Engagement is delayed because:

• The biparietal diameter does not pass the plane of pelvic inlet until the chin is below the level of the ischial spines and the face begins to distend the perineum.
• Moulding does not occur as in vertex presentation.

Mento-posterior position

• so the head is delivered as mento-anterior.
• Deep transverse arrest of the face: when the chin rotates 1/8 circle anteriorly.
• Persistent mento-posterior: when no rotation occurs.
• Direct mento-posterior: When the chin rotates 1/8 circle posteriorly.

In the last 3 conditions no further progress occurs and labour is obstructed.

Direct mento-posterior, unlike direct occipito-posterior, cannot be delivered because:

• Delivery should occur by extension while the head is already maximally extended.
• As the length of the sacrum is 10 cm and that of neck is only 5 cm, the shoulders enter the pelvis and become impacted while the head still in the pelvis, thus the labour is obstructed.

Management of Labour

Exclude: - Foetal anomalies and - Contracted pelvis.

Mento-anterior

• First stage: as in occipito-posterior.
• Spontaneous delivery usually occurs.
• Forceps delivery may be indicated in prolonged 2nd stage.
• Episiotomy is necessary because of over distension of the vulva.

Mento-posterior

• First stage: as mento-anterior.
• Wait for long anterior rotation of the mentum 3/8 circle and the head will be delivered as mento-anterior. During this period oxytocin is used to compete inertia which is common in such conditions as long as there is no contraindication. Failure of this long rotation is more common than in occipito-posterior position so earlier interference is usually indicated.
• Caesarean section: which is the safest and the current alternative in modern obstetrics.
• Manual rotation and forceps extraction as mento-anterior, or
• Rotation and extraction by Kielland forceps.
• In the last 2 methods the head should be engaged but they are hazardous to both the mother and foetus so they are nearly out of modern obstetrics.
• Craniotomy: if the foetus is dead.

The face of the foetus is oedematous after delivery so the mother is assured that this will be spontaneously relieved within few days.

Complications

See complications of malpresentations and malposition.

• Dystocia : Guidelines, reviews

Face Presentation

• First Online: 02 August 2023

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• Shubhra Agarwal 2 &
• Suchitra Pandit 3  

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Face presentation is defined as a cephalic presentation in which the presenting part is face and it occurs due to factors that lead to extension of of fetal head. It is a rare obstetric presentation and may not be encountered even in the entire carrier of an obstetrician.

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Shaffer BL. Face presentation: predictors and delivery route. Am J Obstet Gynecol. 2006;194:e10–2.

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Schwartz Z, Dgani R, Lancet M, Kessler I. Face presentation. Aust N Z J Obstet Gynaecol. 1986;26:172–6.

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Westgren M, et al. Face presentation in modern obstetrics-a study with special reference to fetal long term morbidity. Z Geburtshilfe Perinatol. 1984;188(2):87–9.

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Department of Obstetrics and Gynaecology, TMMC&RC, Moradabad, India

Shubhra Agarwal

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Suchitra Pandit

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Department of Obstetrics and Gynecology, Sarojini Naidu Medical College, Agra, Uttar Pradesh, India

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About this chapter

Agarwal, S., Pandit, S. (2023). Face Presentation. In: Garg, R. (eds) Labour and Delivery. Springer, Singapore. https://doi.org/10.1007/978-981-19-6145-8_6

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Management of face presentation, face and lip edema in a primary healthcare facility case report, Mbengwi, Cameroon

Nzozone henry fomukong.

1 Microhealth Global Medical Centre, Mbengwi, Cameroon

2 Department of Medicine and Surgery, Faculty of Health Sciences University of Buea, Buea, Cameroon

Ngouagna Edwin

Mandeng ma linwa edgar, ngwayu claude nkfusai.

3 Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon

4 Cameroon Baptist Convention Health Services (CBCHS), Yaoundé, Cameroon

Yunga Patience Ijang

5 Department of Public Health, School of Health Sciences, Catholic University of Central Africa, Box 1110, Yaoundé, Cameroon

Joyce Shirinde

6 School of Health Systems and Public Health, Faculty of Health Sciences, University of Pretoria Private Bag X323, Gezina, Pretoria, 0001, Pretoria, South Africa

Samuel Nambile Cumber

7 Institute of Medicine, Department of Public Health and Community Medicine (EPSO), University of Gothenburg, Box 414, SE - 405 30 Gothenburg, Sweden

8 Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa

Face presentation is a rare obstetric event and most practitioners will go through their carriers without ever meeting one. Face presentation can be delivered vaginally only if the foetus is in the mentum anterior position. More than half of the cases of face presentation are delivered by caesarean section. Newborn infants with face presentation usually have severe facial oedema, facial bruising or ecchymosis. These syndromic facial features usually resolved within 24-48 hours.

Introduction

Face presentation is a rare unanticipated obstetric event characterized by a longitudinal lie and full extension of the foetal head on the neck with the occiput against the upper back [ 1 - 3 ]. Face presentation occurs in 0.1-0.2% of deliveries [ 3 - 5 ] but is more common in black women and in multiparous women [ 5 ]. Studies have shown that 60 per cent of face presentations have one or more of the following risk factors: small fetus, large fetus, high parity, previous caesarean section (CS), contracted pelvis, fetopelvic disproportion, cord around the neck multiple pregnancy, hypertensive disorders of pregnancy, polyhydramnios, uterine or nuchal cord anomaly. But 40 per cent of face presentations occur with none of these factors [ 6 , 7 ]. A vaginal birth at term is possible only if the fetus is in the mentum anterior position. More than half of cases of face presentation are delivered by caesarean section [ 4 ]. Newborn infants with face presentation usually have severe facial edema, facial bruising or ecchymosis [ 8 ]. Repeated vaginal examination to assess the presenting part and the progress of labor may lead to bruises in the face as well as damage to the eyes.

Patient and observation

Case presentation: a 21 year old primigravida at 40 weeks gestation from the last normal menstrual period referred to our facility for prolonged second stage of labor after visiting two health centres. She labored for a total of 14hrs, membrane ruptured spontaneously 12hrs before referral. Amniotic fluid was documented by midwife to be clear. She attended antenatal clinics in Mbengwi health centre 5 times, was diagnosed of hepatitis B during antenatal consultations, received no treatment. She did not do any ultrasound due to financial constraints. On examination, she was healthy, in painful distress, blood pressure 131/76mmhg, pulse 85 beats/min, temperature 37.2 o C SPO2 98%. On abdominal exams, uterus was gravid, fundal height 35cm, lie longitudinal, fetal heart rate 137bpm, cephalic presentation, engaged 2/5, with moderate contractions of 2 in 10 minutes. On vaginal examination, cervix was fully dilated, membranes ruptured, presenting part was face, mentum anterior. The conclusion made was mento-anterior face presentation ( Figure 1 ). Paturient was counseled, labor was augmented with 1 amp of oxytocin in 500ml of glucose 5% and started at 10drops/mins. Ten minutes later she delivered a male baby with Apgar score 6/10, 8/10 on the first and fifth minute. The baby weighed 3.2kg, length was 50cm, and head circumference was 41cm. Syndromic facial appearance with marked edema at the baby's lips, face and scalp was evident and he had bruising on the right nasolabial groove and right cheeks ( Figure 2 ). Physical examination of the infant's respiratory system, cardiovascular system, and his abdominal examination were normal, as was his neurological examination. Placenta was delivered by controlled cord traction 5mins later with all cotyledons. Delivery was complicated by a second degree perineal tear. Perineal tear was repaired with absorbable suture under local anaesthesia. Estimated blood lost was 350ml. baby received Hepatitis B immunoglobulins, hepatitis B vaccine and vitamin K were administered to the baby. 24 hours later, facial swellings resolved ( Figure 3 ), baby breast feeds well. Baby and mother were discharged on day 3 postpartum all fine.

Men-tum anterior face presentation

Bruising, marked lip and facial edema

Baby 24 hours later with all syndromic facial features resolved

Ethics : informed consent: written informed consent was obtained from the patient's parents for the publication of this case report.

Face presentation is a rare obstetric event and most practitioner will go through their carriers without ever meeting one [ 3 ]. We presented a case of face presentation noticed in the delivery room on digital examination in a patient with no risk factors. In a poor resource setting as ours where ultrasound is not readily available, this event is often scary and confusing to most midwives and nurses. This may prompt repeated vaginal exams for confirmation of presentation. This intend will lead to bruising of the baby's face and delay effective management [ 8 ]. Exact knowledge about the fetal position and level is important for providing the correct management of this malpresentation. When face presentation is diagnosed, around 60% of cases are in the mentum anterior position, 25% are mentum posterior and 15% are mentum transverse [ 5 ]. The patient presented the most common form of face presentation (mentum anterior). Labor was augmented, vaginal delivery was attempted and successfully conducted. Facial bruising, lip and face edema are very common complication of face presentation. These complications usually resolve within 24-48 hours [ 9 , 10 ] in this case facial edema completely resolved within 24hours ( Figure 3 ) and baby breastfeed well.

Repeated vaginal exams should be avoided when presenting part is unsure. Vaginal delivery should be attemped only on mentum anterior face presentation, in other cases, emergency ceserian section should be performed. Syndromic facial features in babies born from face presentation resolve completely within 24-48 hours.

Competing interests

The authors declare no competing interests.

Acknowledgements

We thank the participant of this study.

Authors’ contributions

NHF, NE, MMLE, NCN, YPI, FB, JS and SNC conceived the case series, assisted with the study design and participant enrollment, designed the study protocol and collected the data. NE, MMLE, NCN and SNC assisted in interpretation of results and wrote the manuscript. All authors read and approved the final manuscript.

Diagnosis and management of face presentation

• PMID: 7005774

Face presentation is an unusual complication of pregnancy; it occurs once in every 500 to 600 deliveries. Prematurity, fetal macrosomia, anencephaly, and cephalopelvic disproportion (CPD) are the major obstetric factors that predispose the fetus to face presentation. Although the mechanisms of labor in face presentation are different from those of simple vertex presentation, there is no consistent alteration in the duration of labor in the absence of underlying CPD. When disproportion does not exist and gross anomalies are not present, the prognosis for spontaneous vaginal delivery is excellent. The majority of perinatal losses reported in face presentation have resulted from traumatic operative vaginal deliveries, specifically version and extraction and midforceps rotations. Recent experience at this institution with a limited series of face presentations demonstrates that, with careful intrapartum surveillance, delivery can be accomplished with no increase in risk to either mother or fetus.

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• Delivery, Obstetric
• Labor Presentation*
• Labor, Obstetric

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Home » Mechanism of Labour in Face Presentation

Mechanism of Labour in Face Presentation

Here in this article, we will discuss the one of the rare variety…

Here in this article, we will discuss one of the rare varieties of cephalic presentation is the face. It is more common in multiparae.

Lie – Longitudinal Presentation – Cephalic Presenting part – Face Attitude – Complete flexion of the limbs or complete extension of the head Denominator – Mentum Position – 4 Positions of the face in relation to the left and right sacroiliac joints or the right and left iliopectineal eminences.

1st Face- Right mento-posterior (RMP) 2nd Face- Left mento-posterior (LMP) 3rd Face- Left mento-anterior (LMA), Commonest position 4th Face- Right mento-anterior (RMA)

Some of the reasons are-

-Multi parity with a pendulous abdomen -Contracted pelvis / Flat pelvis – Pelvic tumors -Congenital malformations -Twist of the cord around the neck

MECHANISM OF LABOUR ( Mento-anterior, LMA / RMA) –

• Engagement – The engaging diameter is the right oblique in LMA, left in RMA, and the mentum lies at the iliopectineal eminence and the glabella to the opposite sacroiliac joint. The engaging diameter of the head is submento-bregmatic 9.5 cm in a fully extended head and the engagement becomes delayed.
• Descent and extension – With the increasing extension, the chin touch the pelvic  floor.
• Internal rotation of chin – It occurs through 1/8th of a circle anteriorly, and the mentum comes behind the symphysis pubis and this continues until the submentum hinges under the pubic arch.
• Delivery of the head – Now the head is born by flexion, the chin, face, brow, vertex, and the occiput is released. Submento- vertical 11.5 cm distend the vulval outlet.
• Restitution – It occurs through 1/8th of a circle opposite to the direction of internal rotation.
• External rotation – Occurs 1/8th of a circle to the same side of restitution so the face looks toward the left thigh in LMA and right thigh in RMA.
• Lateral flexion – The anterior shoulder followed by the posterior shoulder and then the trunk is released by lateral flexion.

Mento-posterior position (20-25%) (RMP / LMP) –

-Anterior rotation of the mentum occurs in only 20% of cases.

– In 80%, incomplete anterior rotation, non-rotation or short posterior rotation of the mentum occurs. ( All in these positions arrest occurs with average size pelvis and fetal head and no spontaneous delivery in persistent mento-posterior position.)

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Mechanism of labour

Aug 01, 2012

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Mechanism of labour. Descent. Relation to practice. Primip -may occur before the onset of labour Multip -not until onset of labour due to laxity of uterine/ abdo muscles Educate re optimal fetal positioning Adequate abdominal palpation Upright and mobile once in

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Mechanism of labour Descent Relation to practice Primip-may occur before the onset of labour Multip-not until onset of labour due to laxity of uterine/abdo muscles Educate re optimal fetal positioning Adequate abdominal palpation Upright and mobile once in Labour, continual support The fetus begins to descend into the pelvis due to the force of gravity and downward pressure of the contractions Claire Allan

Mechanism of labour Flexion Relation to practice Upright position to assist with gravity When resting, adopt the left lateral position (OFP) Observation of the contractions-are they regular, do they appear to be increasing in strength and becoming expulsive? As the fetus descends the chin touches the chest (arms begin to cross) and the attitude of flexion is adopted. This is increased further when the head meets the resistance of the birth canal Claire Allan

Mechanism of labour Internal rotation Relation to practice Fully dilated, station of the head Vertex may or may not be visible Upright position-kneeling, squatting May be spontaneously pushing Would you encourage mechanical pushing or allow for natural descent? As the occiput reaches the resistance of the pelvic floor, it rotates forward 45 degrees. The slope of the pelvic floor aids this rotation forward and allows the head to emerge in the longest diameter of the pelvis (anterposteior) Claire Allan

Mechanism of labour Crowning Relation to practice May be spontaneously/mechanically pushing or still breathing through contractions, how long can the second stage last? Introverted in her behaviour and may adopt alternative Position, bending towards the floor with knees apart The head has crowned when it escapes under the pubic arch and no longer recedes between contractions because the widest transverse diameter of the head is born Extension With slight extension the bregma, forehead, face and chin will pass over the perineum and the head is born Claire Allan

Mechanism of labour Restitution Relation to practice No need to do anything, allow time for restitution (you may see a small part of the anterior shoulder). Wait for the next contraction to deliver the remainder of the body (Dr’s are often too quick in trying to deliver the body) When the head is born it will turn to the left or the right, righting itself with the shoulders. The shoulders then rotate (similar action to that of the head) and lie in the anteroposterior diameter of the pelvis. Rotation follows the same direction as restitution Claire Allan

Mechanism of labour Lateral flexion Relation to practice If the woman is on all fours or leaning forward then the posterior shoulder may be born first due to gravity and the effect of the birth canal- the curve of carus-this causes the trunk of the baby to flex sideways as it is born In most supine or semi recumbent birthing positions the anterior shoulder will be born first (under the pubic arch) and the posterior shoulder will pass over the perineum Claire Allan

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