It is within this group, who constitute most breech fetuses at term, that a selective trial of labor will have the greatest benefit 36 Table CT, computed tomography. Measurement of the bony pelvis is performed to exclude borderline pelvic diameters. I advocate the use of radiologic measurement of the maternal bony pelvis.
Computed tomography scan reliably measures pelvic dimensions and the attitude of the fetal head. Magnetic resonance imaging also has been successfully used in this setting. Gimovsky and associates 38 expanded this to include a midpelvic diameter of greater than 10 cm Table Several authors have demonstrated the efficacy of this measure. Results of X-ray pelvimetry in a group of women undergoing a successful trial of labor under protocol. Because most patients will have undergone a failed attempt at ECV, I obtain pelvimetry at that time for the patient selected for a trial of labor.
Patients in whom we are unable to convert a breech presentation are unlikely to undergo spontaneous conversion. Alternatively, pelvimetry may be obtained on presentation in early labor. Computed tomography pelvimetric study. Lateral digital scout view for measurement of the anteroposterior diameters of the inlet and midpelvis. Anteroposterior digital scout view for measurement of the transverse diameter of the inlet and the interspinous diameter. Axial section through the femoral foveae.
This measurement tends to overestimate the interspinous diameter. When a trial of labor is undertaken with a breech-presenting fetus, it is crucial for an expedited cesarean delivery to be continuously available. The usual indicators of fetal well-being, as well as the adequacy of the progression of labor, will give rise to the indication for cesarean delivery on occasion.
The criteria clinically used in supervising the labor of a cephalic fetus should be applied to the selected term breech fetus. In my experience, as well as others, cervical ripening, oxytocin induction, and partographic analysis of labor are safe and efficacious. Augmentation, when indicated, should call for a thoughtful re-evaluation of all aspects of the situation. For example, is the fetal size less than g? Has descent occurred progressively during the second stage?
Cesarean delivery should be used liberally in all other circumstances. Fetal surveillance during labor and delivery should be continuous. After spontaneous rupture of membranes, internal monitoring may be used. Fetal heart rate patterns, particularly in the second stage of labor, may have pronounced variable decelerations.
In breech labor and delivery, compromise to the umbilical circulation may be more frequent but generally is without sequelae. In addition, the intensity and duration of vagal stimulation with its concomitant effects on the fetal heart rate is different than in cephalic labor and delivery.
Study of acid—base status at birth demonstrates a tendency to respiratory acidosis in breech vaginal delivery. This might explain a greater proportion of infants with lower Apgar scores at 1 minute. However, the base deficit in these infants generally is within the normal range.
Anesthesia considerations dictate the usefulness of regional anesthesia, as opposed to earlier approaches that used a combination of local and general techniques. As shown by Crawford, 42 regional anesthesia prevents premature maternal expulsive efforts, which should enhance the safety of delivery Table The second stage of labor should be managed under double-setup conditions. A gowned and gloved assistant, as well as anesthesia and pediatrics personnel, should be present.
The patient should be instructed and encouraged to push effectively. The fetal heart rate should be continuously monitored. A nullipara should be allowed to push for up to 2 hours, a multipara up to 1 hour. If delivery is not imminent, cesarean delivery should be performed, the diagnosis being a failure of descent. After lateral flexion of the trunk, the anterior hip is forced against and underneath the symphysis.
Expulsion follows, with delivery of the anterior and then the posterior buttock. Using a modified Bracht maneuver, a warm wet towel is placed around the fetal abdomen, and the fetus is grasped on the posterior aspect of the fetal pelvic girdle with care to avoid the fetal kidneys and adrenal.
A gentle downward traction is exerted. After the buttocks are fully expulsed, the back is born by rotation anteriorly. This allows the shoulders to enter the pelvis in the transverse diameter of the pelvic inlet.
If there is a failure of anterior rotation, the fetus will be born as a posterior breech, and the sequence of maneuvers used to help in delivery will differ as appropriate. As the anterior shoulder is seen at the introitus, the operator sweeps the right humerus across the infant's chest. With the infant delivered to the umbilicus, some authors recommend the use of uterine relaxants to facilitate the remainder of the delivery. The use of general anesthesia with halothane has been supplanted by parenteral betamimetics.
We have used small aliquots of intravenous nitroglycerin for this purpose. A Mauriceau—Smellie—Viet maneuver follows Fig. The fetus is placed abdomen down on the operator's right arm. The left hand supports the fetal neck.
The index and middle fingers of the right hand are placed on the fetal maxilla to help maintain flexion of the head. The assistant may apply suprapubic pressure to expel the after-coming head Naujok maneuver; Fig.
When delivery is further complicated by rotation of the fetal back posteriorly, a Prague maneuver allows for delivery of the occiput posterior breech variant. Forceps may be used to facilitate delivery of the after-coming head Fig. Maintenance of head flexion is crucial.
Traction is not required. The Piper forceps are specially designed for this task 45 and act as a class 1 lever. Because the fetal head is visible and should be aligned as in an occiput anterior position, any outlet forceps that may be applied as a simple pelvic application are indicated. Elliott forceps are particularly useful in this situation. Use of forceps may be helpful in a nulligravida or when the fetus is small and at term less than g.
The infant then should be handed to the pediatrician in attendance. A segment of umbilical cord for acid—base analysis should be routinely obtained. Attention then can be directed to completion of the third stage of labor, as well as the repair of the episiotomy and genital tract lacerations. A full dictated operative note should be completed at the time of delivery. The entire process of the labor, delivery, and immediate neonatal outcome should be referenced.
Mention of each specific step is warranted, along with clinical observations regarding the relative ease or difficulty of the delivery process. Most breech-presenting fetuses will be born by cesarean delivery. Attention to the details of delivery are of no less consequence in this group. When cesarean delivery is selected, the fetus should be evaluated before surgery using bedside ultrasound examination. A careful review of the fetus to diagnose extension of the head, the presence or absence of nuchal arms, and the location of the placenta should be made.
Although estimates of fetal weight may be less accurate for breech-presenting fetuses, an estimated fetal weight should be made using a standardized formula. These observations may be important in understanding neonatal concerns after cesarean delivery.
They allow both physician and patient to estimate the fetal condition just before birth. Important observations that have been confirmed before delivery include the presence of abnormal postures, broken bones, and the occasional transverse lie or even an undiagnosed second twin.
Cesarean delivery should be expedited if the patient is in labor. Short-term tocolysis has been used so that the most appropriate anesthesia can be administered.
Emergency cesarean delivery, with the greater risks of morbidity for both mother and child, should be chosen as a last resort. The abdomen generally is opened with a transverse-type incision. Surgical choice of incision may vary by maternal habitus, prior surgery, or operator preference.
Any incision may be used, as long as adequate visualization occurs and mobilization of the fetus is expedited. Palpation of the uterus before the uterine incision should confirm the presentation. A low cervical transverse incision should be made carefully in the midline and extended to a depth necessary to expose the membranes. This is easier to do in practice if the membranes are intact.
The important point is that the fetus may be incidentally incised if care is not taken. The infant born by cesarean delivery should be carefully examined after birth in this regard. The fetus should be rotated if necessary so that the back is anterior before delivery. The assistant applies fundal pressure as the operator guides the buttocks up through the uterine incision.
The use of force on the fundus allows the after-coming head of the breech fetus to remain in a flexed attitude. This approach also should minimize the loss of flexion of the fetal arms, which may result in a nuchal displacement. A warm, wet towel is wrapped around the fetal abdomen to protect the fetus from traumatic injury and to mitigate against the onset of breathing movements before delivery.
Thus, by the use of an assistant giving fundal pressure, delivery of a breech fetus at cesarean delivery mirrors an assisted vaginal breech delivery. Avoid total breech extraction at cesarean delivery: it is inherently more of a risk to the fetus than an assisted or spontaneous breech delivery. As with vaginal delivery, a section of umbilical cord should be sent for acid—base status. Attention is given to the description of the delivery process within the operative report.
The most important factor in neonatal outcome for all infants is gestational age. This also is true for breech infants. Many series, generally retrospective, some aided by meta-analysis, have studied the effect of mode of delivery on both immediate and long-term outcome. In the absence of congenital anomalies, laboring fetuses born ultimately by cesarean or vaginal delivery have similar outcomes, which are determined by gestational age and weight.
Prolapse of the umbilical cord that occurs before hospitalization or goes unrecognized, although uncommon at term, plays a serious and compromising role for preterm infants. In the single footling breech presentation, one of the baby's feet is pointed toward your cervix. In the double footling breech presentation, both of the baby's feet are pointed toward your cervix.
In a transverse lie, the baby is lying horizontally in your uterus and may be facing up toward your head or down toward your feet. Babies settle this way less than 1 percent of the time, but it happens more commonly if you're carrying multiples or deliver before your due date. If your baby stays in a transverse lie until the end of your pregnancy, it can be dangerous for delivery. Your provider will likely schedule a c-section or attempt an external cephalic version , which is highly successful for turning babies in this position.
In rare cases, your baby may lie diagonally in your uterus, with his rump facing the side of your body at an angle. Like the transverse lie, this position is more common earlier in pregnancy, and it's likely your provider will intervene if your baby is still in the oblique lie at the end of your third trimester. BabyCenter's editorial team is committed to providing the most helpful and trustworthy pregnancy and parenting information in the world.
When creating and updating content, we rely on credible sources: respected health organizations, professional groups of doctors and other experts, and published studies in peer-reviewed journals.
We believe you should always know the source of the information you're seeing. Learn more about our editorial and medical review policies. Ahmad A et al. Association of fetal position at onset of labor and mode of delivery: A prospective cohort study. Breech presentation. Hankins GD. Transverse lie. American Journal of Perinatology 7 1 A breech presentation could be a frank breech, footling breech or complete breech position. This is also sometimes called an incomplete breech position. Some breech babies can be safely delivered vaginally but not without an increased risk of damage to nerves, organs, bones or fetal head entrapment.
In addition, there is a much higher risk of umbilical cord prolapse UCP that can significantly cut off much needed blood and oxygen to your baby leading to hypoxic ischemic encephalopathy HIE or even fetal death. For these reasons, many breech babies are delivered by cesarean section C-section. If your baby is in a transverse lie he or she cannot be delivered vaginally because the entire body would not be able to fit through the birth canal sideways.
If labor is allowed to continue with a transverse lie it could lead to a uterine rupture and a lack of blood and oxygen to your baby. If they're still breech at around 36 weeks' gestation, the obstetrician and midwife will discuss your options for a safe delivery.
If your baby is in a breech position at 36 weeks, you'll usually be offered an external cephalic version ECV. This is when a healthcare professional, such as an obstetrician, tries to turn the baby into a head-down position by applying pressure on your abdomen. It's a safe procedure, although it can be a bit uncomfortable.
If an ECV does not work, you'll need to discuss your options for a vaginal birth or caesarean section with your midwife and obstetrician. If you plan a caesarean and then go into labour before the operation, your obstetrician will assess whether it's safe to proceed with the caesarean delivery.
If the baby is close to being born, it may be safer for you to have a vaginal breech birth.
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