After engagement, the fourth maneuver shows the breech to be beneath the symphysis. he accuracy of this palpation varies (Lydon-Rochelle, 1993; Nassar, 2006). hus, with suspected breech presentation-or any presentation other than cephalic-sonographic evaluation is indicated.
During cervical examination with a frank breech, no feet are appreciated, but the fetal ischil tuberosities, sacrum, and anus are usually palpable. Ater urther fetal descent, the external genitalia may also be distinguished. When labor is prolonged, the fetal buttocks may become markedly swollen, rendering digital diferentiation of a face and breech diicult. In some cases, the anus may be mistaken for the mouth and the ischial tuberosities for the malar eminences. With careul examination, however, the inger encounters muscular resistance with the anus, whereas the hard, less yielding jaws are felt through the mouth. The finger, upon removal from the anus, may be stained with meconium. The mouth and malar eminences form a triangular shape, whereas the ischial tuberosities and anus lie in a straight line. With a complete breech, the feet may be felt alongside the buttocks. In footling presentations, one or both feet are inferior to the buttocks.
The fetal sacrum and its spinous processes are palpated to establish position. As with cephalic presentations, fetal position is designated to reflect the relations of the fetal sacrum to the maternal pelvis. Positions include left sacrum anterior (LSA) , right sacrum anterior (RSA), left sacrum posterior (LSP), right sacrum posterior (RSP), and sacrum transverse (ST).
Multiple factors aid determination of the best delivery route for a given mother-fetus pair. These include fetal characteristics, maternal pelvic dimensions, coexistent pregnancy complications, provider experience, patient preference, hospital capabilities, and gestational age.
Compared with their term counterparts, preterm breech fetuses have distinct complications related to their small size and immaturity. For example, rates of head entrapment, birth trauma, and perinatal mortality can be greater. Accordingly, separate dis cussions of term and preterm breech fetuses are more appropriate.
Current obstetrical thinking regarding vaginal delivery of the term breech fetus has been tremendously inluenced by results of the Term Breech Trial (Hannah, 2000). his trial included 1041 women randomly assigned to planned cesarean and 1042 to planned vaginal delivery. In the planned vaginal delivery group, 57 percent were actually delivered vaginally. Planned cesarean delivery was associated with a lower risk of perinatal mortality compared with planned vaginal delivery-3 per 1000 versus 13 per 1000. Cesarean delivery was also associated with a lower risk of "serious" neonatal morbidity-1.4 versus 3.8 percent. Short term maternal morbidity was similar between groups.
Critics of the Term Breech Trial emphasize that fewer than 10 percent of candidates underwent radiological pelvimetry. Also, most of the outcomes included in the "serious" neonatal morbidity composite did not actually portend long-term infant disability (Whyte, 2004).