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Emergency operative delivery is associated with high fetal and maternal morbidity and mortality. It is of high importance to find means to predict the delivery mode before the onset of labor.This study aimed to investigate the potential of combined sonographic and clinical determination to predict the mode of delivery at term.An observational prospective cohort study was deployed in a tertiary maternity hospital (Emergency County Hospital Craiova). Unselected low-risk primiparous pregnant women were evaluated weekly at term for ultrasound determinations (estimated fetal weight, head descent parameters, occiput posterior, cervical length), Bishop score, and maternal characteristics (age, height, weight). A thorough statistical analysis determined which variables were significantly correlated with the delivery mode.Data from 276 term primiparous women were analyzed. Head descent parameters were strongly and significantly correlated with each other, but only progression distance was correlated with the delivery mode (gestational weeks 37, 38, 41, and the week before delivery). In the week before delivery, measurements of head-to-perineum distance and angle of progression reached almost significant P levels of.055 and.07, respectively. The following variables were significantly correlated with the delivery mode: body mass index in all term evaluations; progression distance for weeks 37 and 38; maternal age for week 39; Bishop score, estimated fetal weight, and occiput posterior for week 40; and body mass index, estimated fetal weight, and progression distance for the week before delivery. We also provided logistic regression equations for each week with correct delivery mode prediction, except for week 38. Cutoff values were established for each significant parameter per week. The cutoff values must be read in conjunction with the area under the curve, which ranged from 0.55 to 0.73, depending on the variable.There are strong and significant correlations among the "head descent" ultrasound measurements at term. Body mass index is predictive of labor outcomes throughout term evaluations. Progression distance and body mass index measured at 37 to 38 weeks' gestation correlate with the delivery mode and apparently can be used to forecast the delivery mode when the pregnancy reaches term. For the week before delivery, measurements of estimated fetal weight and progression distance can be used to forecast the delivery mode, perhaps as part of a policy for pregnant women with prelabor clinical signs. Larger studies with more data, particularly better-balanced data, are needed.

A protracted or arrested active phase of labor represents a difficult dilemma of clinical obstetrics, as the situation has to be handled rapidly. Both unsuccessful operative vaginal delivery or a late Cesarean delivery could lead to serious injuries both to the mother and the fetus. In such clinical circumstances, the need for a “transparent” pelvic canal and objective and precise imaging measurements for the evaluation of labor outcome, instead blind and subjective clinical assessment, is nowhere more pertinent. The use of intrapartum ultrasound is not meant to change the classic algorithm of a prolonged or arrested labor monitoring, but to provide objective and reliable evaluations of the traditional crucial features. In this chapter we discuss the role of ultrasound in optimizing the outcome of prolonged labor.The findings regarding a prolonged first stage of labor in nulliparous demonstrated a better reliability of ultrasound evaluations and a good correlation between sonographic measurements and labor duration and outcome. A head to perineum distance less than 40 mm, an angle of progression of more than 110–120°, a progression distance more than 35 mm and an angle of direction of more than 105° represent good predictors for vaginal delivery and should encourage labor continuation.In the prolonged second stage of labor, head to perineum distance and angle of progression are significantly associated with the median duration and success operative vaginal delivery. Lack of head descent during pushing (angle of progression increase < 15°, head to perineum distance increase < 2mm or lack of the fetal head descent with respect to the infrapubic line) were associated with longer duration of operative vaginal delivery and vacuum extraction failure.Generally, the studies on prolonged labor were designed to evaluate the value of a certain parameter. We believe that it would be beneficial to investigate the value of multivariate analyses that include several parameters following the model of other feto-maternal successful predictions, as the combined test. Perhaps more accurate predictions could be obtained with the inclusion of other useful ultrasound determinations, such as asynclitism, pubic angle evaluation or head deflection estimation. As a matter of fact, when a clinician estimates the prognosis of an obstructed labor, takes into account all these features of the labor mechanism, and the role of ultrasound evaluation is to objectively elucidate by all means the delivery settings.