Radiographic evaluation of breech presentation: is it necessary?

The term breech presentation: Neonatal results and obstetric practices in France

OBJECTIVE

Compare neonatal complications according to the planned mode of delivery and according to whether the women gave birth at a maternity unit that applied "consensus" guidelines.

STUDY DESIGN

The study used the database of the AUDIPOG Sentinel Network (n=71,919 pregnancies between 1994 and 2000). The principal outcome was a composite variable that included neonatal morbidity and mortality. A survey of obstetric practices was sent to 175 maternity units belonging to the network. Consensus guidelines were defined from the survey responses and taken into account in the database analysis.

RESULTS

Neonatal complications did not differ between the group of women with term babies in breech presentation for whom vaginal delivery was planned and those for whom an elective caesarean was planned (adjusted OR=1.33; 95% CI: 0.63-2.80). The survey allowed us to define a set of six criteria for deciding on mode of delivery; it established a consensus, followed by 42% of the maternity units in the study. The rate of neonatal complications among the women with planned vaginal delivery was lower for those giving birth in units that applied the consensus guidelines than among those in the other units: adjusted OR=0.27 (95% CI: 0.09-0.85).

CONCLUSION

The risk of neonatal morbidity according to planned mode of delivery for term breech babies was lower for those giving birth in units that applied the consensus guidelines than among those in the other units.

Breech vaginal delivery at or near term

Three percent to 4% of term fetuses will be breech at delivery. Evidence from randomized controlled trials has found a policy of planned cesarean section to be significantly better for the singleton fetus in breech presentation at term compared to a policy of planned vaginal birth. However, some women may wish to avoid cesarean section and for others, cesarean section may not be possible. We undertook this review to identify factors associated with higher and lower risk of adverse fetal or neonatal outcome at term during vaginal breech delivery. We searched MEDLINE from 1966 to 2002 using the search terms vaginal breech delivery and breech presentation and retrieved all relevant articles. We also reviewed personal references and reference lists of articles retrieved. Women who are older or who have a fetus that is either in footling presentation, has a hyperextended head or is estimated to weigh <2500 g or >4000 g may be at higher risk of adverse fetal outcome. Prolonged labor or not having an experienced clinician at vaginal breech birth may also increase the risk. Women with a fetus in breech presentation at term should be offered the option of delivery by planned cesarean section and should be informed that this will reduce their risk of adverse fetal or neonatal outcome. Practitioners should develop and maintain skills at vaginal breech delivery for those women not wishing or not able to be delivered by cesarean section.

Intrapartum fetal head position I: comparison between transvaginal digital examination and transabdominal ultrasound assessment during the active stage of labor

OBJECTIVE

To test the null hypothesis that no correlation exists between transvaginal digital and the gold standard technique of transabdominal suprapubic ultrasound assessments of fetal head position during labor. A secondary objective was to compare the performance of attending physicians vs. senior residents in depicting fetal head position by transvaginal digital examination in comparison with ultrasound, respectively.

METHODS

Consecutive patients in active labor at term with normal singleton cephalic-presenting fetuses were included. All participants had ruptured membranes, cervical dilation > or = 4 cm and fetal head at ischial spine station -2 or lower. Transvaginal sterile digital examinations were performed by either senior residents or attending physicians and followed immediately by transverse suprapubic transabdominal ultrasound assessments. Examiners were blinded to each other's findings. Power-analyses dictated number of subjects required. Statistical analyses included Chi-square, Cohen's Kappa test and logistic regression analysis. P < 0.05 was considered statistically significant.

RESULTS

One hundred and two patients were studied (n = 102). In only 24% of patients (n = 24), transvaginal digital examinations were consistent with ultrasound assessments (P = 0.002, 95% confidence interval, 16-33). Logistic regression revealed that cervical effacement (P = 0.03) and ischial spine station (P = 0.01) significantly affected the accuracy of transvaginal digital examination. Parity, gestational age, combined spinal epidural anesthesia, cervical dilation, birth weight and examiner experience did not significantly affect accuracy of the examination. The accuracy of the transvaginal digital exams was increased to 47% (n = 48) (95% confidence interval, 37-57) when fetal head position at transvaginal digital examination was recorded as correct if reported within +/- 45 degrees of the ultrasound assessment. The rate of agreement between the two assessment methods for attending physicians vs. residents was 58% vs. 33%, respectively (P = 0.02) with the +/- 45 degrees analysis.

CONCLUSIONS

Using ultrasound assessment as the gold standard, our data demonstrate an overall high rate of error (76%) in transvaginal digital determination of fetal head position during active labor, consistent with the null hypothesis. Attending physicians exhibited an almost two-fold higher success rate in depicting correct fetal head position by physical examination vs. residents in the +/- 45 degrees analysis. Intrapartum ultrasound increases the accuracy of fetal head position assessment during active labor and may serve as an educational tool for physicians in training.

Intrapartum ultrasonographic depiction of fetal malpositioning and mild parietal bone compression in association with large lower segment uterine leiomyoma

With normal flexion of the fetal head prior to and during early normal labor, the fetal biparietal diameter becomes engaged in (and subsequently traverses) the anterior posterior aspect of the pelvic inlet. Thus, the biparietal diameter (characterized sonographically by depiction of the falx cerebri, thalami, and cavum septum pellucidum) will be obtainable upon transverse suprapubic placement of the ultrasound transducer during the first stage of labor. Deflexion, or extension, of the fetal head may be demonstrated sonographically at the level of the cervical spine. Recently, during intrapartum ultrasonographic assessment of a nulliparous patient with a known, large, lower-segment, uterine fibroid, exhibiting poor progress of labor, the fetal biparietal diameter was documented upon midsagittal suprapubic placement of the transducer. In addition, mild compression of the distal parietal fetal bone was demonstrated and considered consistent with compression by the leiomyoma. Following abdominal delivery, due to fetal distress and arrest of descent, significant deflexion of the fetal head (not suspected by intrapartum cervical examinations) and mild parietal bone depression, consistent with the ultrasonographic examination, were noted.