div class=”ChapterContextInformation”>
32. Breech in Labor
32.1 Overview and Purpose
Breech presentation is defined as a fetus in a longitudinal lie with the buttocks or feet closest to the cervix. This occurs in 3–4% of all deliveries. The percentage of breech presentation decreases with advancing gestational age from 22–25% of births prior to 28 weeks’ gestation to 7–15% of births at 32 weeks’ gestation to 3–4% of births at term.
32.2 Etiology for Breech Presentation
Uterine anomalies like septate uterus and bicornuate uterus
Fibroids
Previous breech deliveries
Nulliparity
Placenta previa
Cornu-fundal placentation
Prematurity
CNS malformation
Neck masses
Aneuploidy
Oligo-/polyhydramnios
Fetal abnormalities are observed in 17% of preterm breech deliveries, and at term it’s 9%. Perinatal mortality is 2–4 times higher and mostly associated with malformations and prematurity, irrespective of mode of delivery.
32.3 Types of Breech Presentation
Frank breech (50–70%): Hips flexed, knees extended
Complete breech (5–10%): Hips flexed, knees flexed
Footling or incomplete (10–30%): One or both hips extended, foot presenting
32.3.1 Clinical Presentation
History of subcostal discomfort with solid, non-ballotable, fetal pole palpable at the uterine fundus.
Fetal heart sound auscultation above or around the umbilicus.
Palpation of fetal ischial tuberosities, sacrum, and anus on vaginal examination.
Such observations are imprecise, and it is estimated that 30% of breech presentations are not diagnosed until onset of labor. As abdominal palpation has a sensitivity of 28% and specificity of 94%, ultrasound examination remains the gold standard.
32.3.2 Mode of Delivery
Dilemma starts when patient comes to an obstetrician with breech presentation. There was a dictum “Once a breech, always cesarean delivery.” Till (1959), breech vaginal delivery was the rule. After Wright study showed reduction in perinatal morbidity and mortality with cesarean delivery for breech presentation, cesarean delivery was proposed instead of vaginal breech delivery [1].
Multiple factors are to be considered prior to deciding the route of delivery for breech fetuses. Factors include fetal characteristics, pelvic dimensions, coexistent pregnancy complications, operator experience, patient preference, and hospital capabilities.
32.4 Term and Preterm Breech Fetuses
Preterm babies have different set of risk factors compared to their term counterparts. So it becomes mandatory separate and discuss.
32.4.1 Term Breech Fetus
Overall data regarding the superior perinatal outcome with respect to planned cesarean delivery are conflicting. Term breech trial collaborative group (Hannah 2000) [2] has influenced our thinking pattern regarding vaginal breech delivery. It showed that planned cesarean delivery was associated with lower risk of perinatal mortality compared to planned vaginal delivery—3 per 1000 versus 13 per 1000. Cesarean delivery was associated with a lower serious neonatal morbidity—1.4% versus 3.8%. Critics have demonstrated fallacies in term breech trial, so ACOG has to modify its stance on breech presentation, and now it is recommending that “the decision regarding the mode of delivery should depend on the [2] experience of the health care provider” and “that planned vaginal delivery of a term singleton breech fetus may be reasonable under hospital-specific protocol guidelines.”
In contrast, the presentation et Mode d’Accouchement (PREMODA) study showed no difference in corrected neonatal mortality rates and neonatal outcomes according to delivery mode. In spite of evidences on both sides of debate, rates of planned vaginal delivery attempts continue to decline [3].
32.4.2 Preterm Breech Fetuses
There are no randomized studies regarding preterm breech deliveries; planned cesarean delivery appears to confer a survival advantage. Reddy and associates reported data from the National Institutes of Health, retrospective multicenter cohort study (2012), for deliveries between 24 and 32 weeks of gestation. Fetuses within these gestational ages showed low completion rate, and those who completed were associated with higher neonatal mortality rates compared with planned cesarean delivery. The Maternal Fetal Medicine Committee of the Society of Obstetricians and Gynaecologists of Canada recommends that vaginal breech delivery is reasonable when the estimated fetal weight is >2500 g [4].
32.4.3 Delivery Complications
- 1.
Maternal Morbidity and Mortality: Increased rate of maternal morbidity and perinatal morbidity is anticipated with breech delivery, either vaginal or cesarean. In cesarean delivery, hysterotomy incision gets extended while delivering fetal head, irrespective if manual or with forceps. In vaginal delivery, vaginal wall or cervical lacerations and tears are common. Manipulation during vaginal delivery may cause extended lacerations and episiotomy extensions. Uterine atony and postpartum hemorrhage can occur.
- 2.
Perinatal Morbidity and Mortality: Preterm delivery and breech presentation are common associations. In addition, birth trauma can contribute to mortality. There is no difference between routes of delivery. Fractures of the humerus, clavicle, and femur are more common. In some cases, traction may separate epiphyses. Some rare injuries like upper extremity paralysis, skull fractures, spinal cord injuries, and abdominal visceral injuries are noted.
32.4.4 Imaging Techniques
- 1.
Sonography: Usually performed as part of prenatal care. If not done gross fetal anomalies like hydrocephalus or anencephaly can be ruled out prior to planned vaginal breech delivery. Head flexion can also be determined by sonography. Extension of the head is contraindication for vaginal breech delivery. If sonographic imaging is uncertain, then two-view radiography of the abdomen is useful for head inclination. Biparietal diameter of >90–100 mm is considered as exclusion criteria for vaginal breech delivery as per Roman et al. [5].
- 2.
Pelvimetry: Nowadays, bony pelvis assessment can be done by one-view computed tomography, MRI, or plain film radiography. As per Azria (2012), inlet diameters of the pelvis should be as follows: inlet anteroposterior >105 mm, inlet transverse diameter >120 mm, and midpelvic interspinous diameter >100 mm. Others use maternal-fetal biometry correlation. Michel et al. defined values as follows: the sum of the inlet obstetrical conjugate minus the fetal BPD is >15 mm, the inlet transverse diameter minus the BPD is >25 mm, and the midpelvis interspinous diameter minus BPD is >0 mm [6].
32.4.5 Decision-Making
As per the ACOG guidelines, risk versus benefits should be discussed with the patient and relatives prior to making any decision regarding the route of delivery.
- 1.
Lack of operator experience
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
