Attitudes differ on the value of antenatal radiography in the management of breech deliveries. In every case of breech presentation, a decision must be made as to whether a vaginal delivery can be attempted with safety. This decision is sometimes made on clinical grounds alone, but many investigators recommend radiological pelvimetry for greater accuracy. Apart from its value in diagnosing and determining the type of breech presentation, it may also be helpful in confirming fetal maturity and in detecting abnormalities. A retrospective study was undertaken to discover the influence of antenatal radiography on the management of breech presentations at the National Women's Hospital, Auckland. The study included all deliveries at the hospital. The attitudes of clinicians toward radiological pelvimetry varied widely. There were those who requested it for every patient with a breech presentation, others who never requested it, and many who requested it in specific cases only. It was possible, therefore, to obtain groups of reasonable size for comparison. There were 228 mature singleton breech deliveries during the 2-year study period. Abdominal radiographs were taken of 149 women (65 per cent), either as part of a pelvimetry assessment (68) or to determine the type of presentation (29). In 36 women, the investigation was performed to establish fetal maturity because of unreliable information on gestational age. In 16 women, the radiography was requested to investigate possible fetal abnormality. In the whole series, there were six fetuses (3 per cent) with major abnormalities. Radiological pelvimetry was performed on 86 women (38 per cent), and consisted of an erect lateral pelvic film and a supine antero-posterior abdominal film. Fifty-two of the patients were nulliparous, and 34 were parous. The pelvis was classed as favorable in 42 women, 1 7 (40 per cent) of whom were delivered by cesarean section. Four had elective sections because of footling presentation, and one had previous myomectomy. Twelve women had emergency sections because of indications arising during labor. The pelvis was borderline in 26 women, 16 (61 per cent) of whom were delivered by cesarean section. In 18 patients, the pelvis was unfavorable, and 16 of them (89 per cent) were delivered by cesarean section. The only babies delivered vaginally were two small infants weighing 2.6 and 2.9 kg, respectively, both after short labors. The overall cesarean section rate was greater in the pelvimetry group (57 per cent), as compared to those without pelvimetry (44 per cent). Elective cesarean section was performed in 21 per cent of the women with flexed breech, but in only 6 per cent of those with extended leg breech. The cesarean section rate was similar in the nulliparous patients in both groups, but significantly greater in the parous patients who had pelvimetry (56 compared to 36 per cent, P < 0.05). After vaginal deliveries, the condition of the infants from those patients who had had pelvimetry (as compared with those who had not) was better in terms of fewer with low Apgar scores, of less physical trauma, and of a reduction in neonatal intensive care requirements. There was a similar, though less marked, trend in the condition of infants born by cesarean section during labor. As expected, there was no difference among the infants born by elective cesarean section. The infants born vaginally through pelvises reported as favorable did as well as the infants born by elective cesarean section. These two groups were similar in terms of maternal height, age, parity, and birth weight. Trauma to the infants in the pelvimetry group was represented by one with a cephalohematoma and two with extensive superficial bruising, as compared to five with cephalohematomas, eight with extensive superficial bruising, and one with a fractured right temporal bone in the nonpelvimetry group. In all groups, the main reason for admission to the neonatal intensive care unit was hypoxia (40 of 65 admissions). The fetal outcome in women delivered vaginally was not affected by whether the legs were flexed or extended.
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