Breech presentation

Breech Presentation & its Mx

• Definition:is a polar alignment of the fetus in which the fetal buttocks present at the maternal pelvic inlet.

• Incidence:3-5% • Types:frank, incomplete, and complete. frank:60-65% incomplete:25-35% complete:5%

Frank

• The fetal hips are flexed and the knees extended so that the thighs are apposed to the abdomen and the lower legs to the chest The buttocks are the most dependent part of the fetus.

Incomplete

• In incomplete breech presentation, the fetus has one or both hips incompletely flexed so that some part of the fetal lower extremity, rather than the buttocks, is the most dependent part (hence the terms single footling or double footling).

Complete

• The fetal hips and knees are both flexed so that the thighs are apposed to the abdomen and the legs lie on the thighs.

• A significant proportion will change to incomplete in labor.

Position

• Described with the fetal sacrum as the reference point.

Thus, it is right sacrum anterior,right sacrum posterior,right sacrum transverse,& so forth.

Factors predisposing

• Fetal factors

anencephaly

chromosomal anomalies

multiple anomalies• Uterine anomalies

uterine septate,uterine bicornuate &unicornuate

Factors….

• Uterine overdistension

polyhydramnios

multiple gestation

• High parity with lax abdomen and uterine musculature

Diagnosis

• Abdominal Leopold’s first-head in the fundus

Leopold’s third-no tapering b/n the buttocks and the body Auscultation-FHR in the upper quadrants • Vaginal –frank:anal orifice,ischial

tuberosities and no feet.

Diagnosis….

-Complete:anal orifice,ischial tuberosities & feet above the buttock

-Incomplete:one or more feet/knees felt

• Ultrasound:in difficult cases and to see associated anomalies,weight estimation and

fetal attitude.

Perinatal mortality

• Feared and serious complication in breech.

• Four fold higher than cephalic.

-malformations -trauma -asphyxia

Perinatal….

• Malformations:NTD,hydrocephaly,trisomies

• Trauma:no time for molding leading to head entrapment

:hyperextension of neck leads to injury

• Asphyxia:cord prolapse(0.4%,5%,10%)

Antepartum Mx

• Less than 36weeks

-expectant as spontaneous version to cephalic is common. -ultrasound for possible anomalies

• Greater than 36weeks

-ECV(External Cephalic Version)

ECV

• External cephalic version (ECV) is a third alternative to vaginal delivery or cesarean delivery for the breech fetus

• Success with ECV varies from 60 to 75 percent• The mechanical goal is to squeeze the fetal vertex

gently out of the fundal area to the transverse and finally into the lower segment of the uterus.

ECV….

• Contraindications:Indications for cesarean delivery irrespective of fetal presentation (eg, placenta previa)

Ruptured membranes Nonreassuring fetal monitoring test

Hyperextended fetal head Significant fetal or uterine anomaly Abruptio placentae

Mechanism of labor

• enters the pelvic inlet in one of the diagonal pelvic diameters.

• Engagement: the bitrochanteric diameter beyond the inlet by vaginal examination, the presenting part may be at -2 to -4 station.

• At the levator ani muscular sling, internal rotation brings the bitrochanteric diameter into the anteroposterior (AP) axis of the pelvis.

Mechanism….

• The breech at the outlet emerge, first as a sacrum transverse, then rotating to sacrum anterior.

• Crowning occurs when the bitrochanteric diameter passes under the pubic symphysis. As the infant emerges, rotation begins, usually toward a sacrum anterior position.

Vaginal delivery

Three types:• A spontaneous breech delivery is one in which the

entire infant delivers vaginally without manual aid. • The assisted breech delivery( partial breech

extraction.) In this delivery, the fetus is allowed to deliver by the forces of uterine contractions and maternal bearing-down efforts until the fetal umbilicus has passed over the mother's perineum. After this, delivery of the legs, trunk, and arms are assisted manually; the head may be delivered manually or with forceps.

Vaginal deliv…..

• A complete breech extraction, in which manual assistance is applied by traction in the groins or on the lower extremities before delivery of the buttocks.

• Contraindicated in singleton breech presentations.

Assisted breech deliv…

• Criteria - No contraindication to vaginal birth (eg, placenta previa) - Absence of fetal anomaly - fetal weight 2000 g –4000g - GA 36 weeks or more - Flexed fetal head, No hyperextension

Assisted….

-Normal progress of labor

-Continuous fetal heart rate monitoring available

- Staff skilled in breech delivery and facilities available for safe emergency cesarean delivery

Assisted….

-The membranes are left intact because spontaneous rupture of the membranes is more likely to be followed by cord prolapse due to the irregular outline of the breech..

-Oxytocin infusion may be used for inadequate uterine activity in latent phase of labor. In the active phase may be an indicator of fetopelvic disproportion augmentation is not recommended once active labor has commenced .

Steps in assisted breech delivery

• The body is allowed to deliver spontaneously up to the level of the umbilicus

• After the umbilicus has been reached, pressure is applied to the medial aspect of the knee, which causes flexion and subsequent delivery of the lower leg.

Steps…

• The fetal trunk is then wrapped with a towel to provide secure support of the body

• When the scapulae appear at the outlet, the operator may slip a hand over the fetal shoulder from the back , follow the humerus to effect delivery of forearms.

• Delivery of the head by performing the Mauriceau-Smellie-Veit maneuver

Cesarean delivery

• EFW <1,500 or >4,000 g   

• Footling presentation   

• Small pelvis  

• Hyperextended fetal head    

• Absence of expertise   

• Nonreassuring fetal heart rate pattern   

• Arrest of progress