BREECH BIRTH

BREECH BIRTH - Kimberle Vore, MD
BASICS
DESCRIPTION
• At the time of delivery, the fetal buttocks are the presenting part in the maternal pelvis
- Frank breech presentation: The fetal hips are flexed and the knees are extended with the feet near the shoulders; accounts for 60-65% of breech presentations at term.
- Incomplete breech presentation: 1 or both of the fetal hips are incompletely flexed, resulting in some part of the fetal lower extremity as the presenting part. Thus the terms single footling, double footling, knee presentation. Accounts for 25-35% of breech presentations.
- Complete breech: Similar to frank breech except that knees are flexed rather than extended. Accounts for 5% of breech presentations.
• System(s) Affected: Reproductive
ALERT
Pregnancy Considerations
A problem of pregnancy
GENERAL PREVENTION
• External cephalic version
- Conversion of breech to vertex can be attempted after 36 weeks of gestation and if successful allows for vaginal vertex delivery. Success rates 48-78%, with reversion rates back to breech of 2%.
- External cephalic version associated with risk (1-2%) of umbilical cord entanglement, abruptio placenta, preterm labor, premature rupture of membranes, fetal brachycardia, fetal-maternal hemorrhage, and severe maternal discomfort
- Prior to procedure, tocolytics are usually administered and RhoGAM is given to Rh-negative mothers.
- External cephalic version should only be attempted with continuous fetal heart monitoring in the delivery suite, where immediate cesarean delivery can be done
- External cephalic version requires 2 operators, 1 to monitor fetal cardiac activity via ultrasound and holding fetal position, while the 2nd person lifts the buttocks out of the pelvis by abdominal manipulation and then guides the fetal head into the pelvis.
- Contraindications to external cephalic version include multiple pregnancy, nonreassuring fetal monitoring, placenta previa, premature rupture of membranes, abruption, previous uterine surgery, uterine malformation, oligohydramnios, maternal cardiac disease, or major fetal anomalies.
- Successful external cephalic version factors include multiparity, relaxed abdominal wall, adequate amniotic fluid, nonfrank breech, floating presenting part, posterior placenta, and average maternal body weight.
- Failure of external cephalic version associated with maternal obesity, nulliparity, anteriorly located placenta, large fetus, decreased amniotic fluid, frank breech that is engaged in pelvis
• Prevention of fetal anomalies by tight glucose control in diabetics
• Antenatal folate therapy to decrease risk of neural tube detects
EPIDEMIOLOGY
Predominant sex: Female only (affects only women in terms of pregnancy, but affects both sexes of fetuses)
Prevalence
• 3-4% of singleton-term deliveries and up to 15-30% of low-birth-weight infants (2,500 g)
• Breech presentation is common in early pregnancy. At 25-26 weeks, ~20-30% of singleton fetuses are in breech position, but this decreases near term.
RISK FACTORS
• Fetal anomalies including anencephaly, hydrocephalus, trisomy 21 and 21, fetal alcohol syndrome, Potter syndrome, myotomic dystrophy
• Uterine anomalies including bicornate uterus
• Uterine relaxation associated with great parity
• Uterine overdistension as in polyhydramnios or multiple gestation
• Placenta previa
• Placental implantation in cornual-fundal region
• Low-birth-weight or premature infant
• Macrosomia
• Pelvic contractions or irregularly shaped pelvissuch as android or platypelloid pelvis
• Pelvic tumors
• Nulliparity
• Previous history of breech birth
Genetics
Fetal anomalies including anencephaly, hydrocephalus, and trisomy 21 and 18 have higher incidences of breech birth.
ETIOLOGY
Probably a combination of 1 or more of the risk factors listed above
ASSOCIATED CONDITIONS
• See "Risk Factors"
• Congenital hip dislocation is more common in 1st-born (breech) females.

DIAGNOSIS
SIGNS AND SYMPTOMS
• Anus palpable on digital vaginal exam
• Leopold maneuver reveals ballottable head in fundal region
• Mother reports kicking in lower abdomen
• Presenting part not palpable in pelvis near term
TESTS
Imaging
• Ultrasoundconfirms presenting part
• Radiographflat plate of abdomen and pelvimetry to determine extent of head flexion and pelvic measurements (rarely done)
Diagnostic Procedures/Surgery
• Near-term women should be examined to determine presenting part.
• If breech is suspected, an ultrasound should be done to confirm presenting part.
• When breech presentation is confirmed, the option for external version or elective cesarean section should be discussed with the patient.
Pathological Findings
• Congenital malformation among term breech infants: Overall incidence 6-9%
• There is a higher incidence of congenital hip dislocation in infants with breech presentation at term.
DIFFERENTIAL DIAGNOSIS
• In labor, diagnosis is made by vaginal exam and confirmed by ultrasound. Can be confused with face presentation on digital vaginal exam
• In breech presentation, greater trochanter and anus form a straight line. In face presentation, mouth and malar bones form a triangle.
TREATMENT
Inpatient for labor and delivery
GENERAL MEASURES
• Continuous electronic fetal monitoring during labor
• Breech presentation may be converted by external version (see "General Prevention"), but this is not always successful and has risks.
• Currently, the American College of Obstetricians and Gynecologists (ACOG) recommends external version at term and planned cesarean delivery for persistent breech presentation. This recommendation is based on a large randomized clinical trial showing decreased perinatal and neonatal morbidity and mortality in planned breech cesarean delivery (1) [NNT 30] vs planned breech vaginal delivery. There was no difference in maternal morbidity or mortality. (1)[B]
Diet
NPO until delivery accomplished
Activity
Bed rest during labor
SURGERY
• Breech delivery is accomplished either vaginally or by cesarean section
• Most physicians and patients opt for elective cesarean delivery for breech presentation near term, which is usually planned for the 39th week of pregnancy.
• When a patient presents in labor with the fetus in breech position, a decision about a trial of labor or immediate cesarean section must be made. Preferably this decision is made prior to onset of labor.
• Obtain ultrasound to document fetal presentation, check for fetal abnormalities, and estimate fetal weight in deciding candidacy for vaginal delivery.
• The selection for vaginal breech delivery could include
- Breech presentation in advanced labor
- Delivery of a 2nd twin in nonvertex presentation
- Fetus too immature to survive
- Fetus with congenital defects incompatible with life
• Cesarean section procedure
- Prepare for cesarean section by starting IV fluids and obtaining blood type and screen, in all patients, in case needed for emergency.
- A low transverse cesarean section may need to be extended vertically if there is difficulty with head entrapment (this extension produces a weak scar).
- General anesthesia with isoflurane can rapidly relax the uterus and allow delivery of an entrapped after-coming head.
- Delivery is usually accomplished with spinal anesthesia.
- Cord blood gases should be obtained following delivery.
• Vaginal delivery procedures
- Currently not recommended, but may be an option in limited circumstances (see above)
- The candidate for vaginal delivery needs to be attended by a birth attendant skilled in breech delivery, a scrubbed assistant, an anesthesiologist capable of rapid induction of general anesthesia, and an individual skilled in neonatal resuscitation.
- Epidural is preferred anesthesia
- Leave membranes intact as long as possible, to prevent possible cord prolapse
- The patient should not push until fully dilated, due to risk of partial delivery through a cervix that is not fully dilated, which can lead to head entrapment.
- Consider cutting a large episiotomy to allow sufficient room for delivery.
- Use abdominal guidance of fetal head to keep it flexed as it descends into the pelvis.
- The infant should not be touched before the umbilicus crosses the maternal perineum. Traction prior to this point constitutes a complete breech extraction and is associated with higher risk of perinatal morbidity and mortality.
- With the fetal back anterior, maintain downward traction while grasping the fetal hips until the scapula becomes visible.
- Check for nuchal arm.
- As one axilla becomes visible, rotate the infant until the shoulders are oriented anteriorly and posteriorly, allowing their delivery.
- The fetal head is delivered in a face-down position with either piper forceps or manual flexion of the head.
- Cord blood gases should be obtained following delivery.
FOLLOW-UP
PROGNOSIS
• Perinatal morbidity and mortality are much higher in breech births. A large proportion of the deaths are related to congenital abnormalities.
• Successful external cephalic version at term significantly lowers cesarean rate. (2)[A]
• For infants 750-1500 g or 32 weeks gestational age, there is a much higher rate of cerebral hemorrhage and perinatal death associated with vaginal compared to cesarean delivery.
COMPLICATIONS
• Trauma to the head, soft tissue, brachial plexus, and spinal cordnot always prevented by cesarean
• Asphyxia secondary to cord compression or prolapse
• Congenital hip dislocation
PATIENT MONITORING
• Continuous fetal heart rate monitoring should be done during labor and delivery.
• 6-weeks postpartum care as for other deliveries
REFERENCES
1. Term Breech Trial. Lancet. 2000;356(9239):1375
2. External Cephalic Version. ACOG practice bulletin. Num. 13, February. 2000.
3. Committee on Obstetric Practice. ACOG committee opinion. Mode of term singleton breech delivery. Number 265, December 2001. American College of Obstetricians and Gynecologists. Int J Gynaecol Obstet. 2002;77:65-66.
4. Scorza W. Intrapartum management of breech presentation. Clin Perinatol. 1996;23:31-49.
MISCELLANEOUS
• Other notes: Maneuvers of cesarean breech delivery are similar to vaginal breech extraction and can be associated with severe trauma to the infant.
• See also: Placenta Previa; Premature Labor