The sonographic measurement of the ratio between the fetal head circumference and the obstetrical conjugate is accurate in predicting the risk of labor arrest: results from a multicenter prospective study.

BACKGROUND: Labor arrest is estimated to account for approximately one-third of all primary cesarean deliveries, and is associated with an increased risk of adverse maternal and perinatal outcomes. One of the main causes is the mismatch between the size of the birth canal and that of the fetus, a condition usually referred to as cephalopelvic disproportion. OBJECTIVE: This study aimed to describe a new ultrasound predictor of labor arrest leading to cesarean delivery because of suspected cephalopelvic disproportion. STUDY DESIGN: This was a multicenter prospective study conducted at 3 maternity units from January 2021 to January 2022. A nonconsecutive series of singleton pregnancies with cephalic-presenting fetuses, gestational age of 34 weeks+0 days or above, and no contraindication to vaginal delivery attending at the antenatal clinics of each institution were considered eligible. Between 34+0 and 38+0 weeks of gestation, all eligible patients were submitted to transabdominal 2D ultrasound measurement of the obstetrical conjugate. On admission to the labor ward, the fetal head circumference was measured on the standard transthalamic plane by transabdominal ultrasound. The primary outcome of the study was the accuracy of the ratio between the fetal head circumference and the obstetrical conjugate measurement (ie, head circumference/obstetrical conjugate ratio) in predicting the occurrence of cesarean delivery secondary to labor arrest. The secondary outcome was the relationship between the head circumference/obstetrical conjugate ratio and labor duration. RESULTS: A total of 263 women were included. Cesarean delivery for labor arrest was performed in 7.6% (20/263) of the included cases and was associated with more frequent use of epidural analgesia (95.0% vs 45.7%; P<.001), longer second stage of labor (193 [120-240] vs 34.0 [13.8-66.5] minutes; P=.002), shorter obstetrical conjugate (111 [108-114] vs 121 [116-125] mm; P<.001), higher head circumference/obstetrical conjugate ratio (3.2 [3.2-3.35] vs 2.9 [2.8-3.0]; P<.001), and higher birthweight (3678 [3501-3916] vs 3352 [3095-3680] g; P=.003) compared with vaginal delivery. At logistic regression analysis, the head circumference/obstetrical conjugate ratio expressed as Z-score was the only parameter independently associated with risk of cesarean delivery for labor arrest (odds ratio, 8.8; 95% confidence interval, 3.6-21.7) and had higher accuracy in predicting cesarean delivery compared with the accuracy of fetal head circumference and obstetrical conjugate alone, with an area under the curve of 0.91 (95% confidence interval, 81.7-99.5; P<.001). A positive correlation between the head circumference/obstetrical conjugate ratio and length of the second stage of labor was found (Pearson coefficient, 0.16; P=.018). CONCLUSION: Our study, conducted on an unselected low-risk population, demonstrated that the head circumference/obstetrical conjugate ratio is a reliable antenatal predictor of labor arrest leading to cesarean delivery.

Cephalopelvic disproportion as primary diagnosis for cesarean section: Role of neonatal birthweight in relation to maternal height at a Hospital in Merida, Mexico.

OBJECTIVE: To analyze the association between newborn and maternal characteristics and the risk for cesarean section (CS) due to cephalopelvic disproportion (CPD) and non-CPD causes compared to vaginal deliveries (VD) in a sample of infants and mothers from Merida, Yucatan, Mexico. METHODS: The final sample consisted of 3453 single, live, and term infants born between January 2016 and May 2017 at the Maternal-Infant Hospital in Merida and their mothers (aged ≥19 years). The mode of delivery was established as the dependent variables: (a) VD, (b) CS due to CPD, and (c) non-CPD CS. Independent variables were maternal height and weight, the number of previous VD, newborn weight, and neonatal birthweight (BW) index/maternal height index. A multinomial regression model was used to analyze the association between newborn and maternal characteristics and outcome variable. RESULTS: By mode of delivery, 2124 (62%) births corresponded to VD, 1042 (30%) to non-CPDCS, and 287 (8%) to CS due to CPD. Mothers who had CS due to CPD weighed more at the end of their pregnancy and were shorter. Maternal age and weight increased the risk for having CS due to CPD compared to VD and maternal height, and the number of previous VD reduces the risk for experiencing CS due to CPD compared to vaginal births. The relative risk ratio for higher neonatal BW/maternal height index was significant for CS due to CPD and non-CPD CS. CONCLUSION: According to our results from a public hospital in Merida, Mexico, CPD is a result of the interrelation of maternal and fetal size, rather than an independent result of maternal height or BW.

Emergency cesarean section rate between women with gestational diabetes and normal pregnant women.

OBJECTIVE: Gestational diabetes mellitus (GDM) has been related to various maternal and neonatal complications. The degree to which GDM is related to an increased rate of cesarean section is less certain. This study was aimed at comparing the incidence of emergency cesarean delivery between pregnant women with GDM and normal pregnant women. MATERIALS AND METHODS: The study group consisted of 237 term, singleton pregnant women with GDM. Another 237 uncomplicated, normal pregnant women were randomly selected and served as the comparison group. Those who were scheduled for elective cesarean delivery and overt DM were excluded. Data were retrieved from medical records, including demographic data, antenatal and intrapartum care data, route of delivery, indications for cesarean delivery, and neonatal outcomes. RESULTS: The study group had a significantly higher mean age and body mass index, and the participants were more likely to be overweight/obese. The rate of emergency cesarean delivery was significantly higher in the study group than in the comparison group (31.6% vs. 19.4%, p = 0.002). The study group was more likely to have Cephalo-pelvic disproportion (CPD) (20.3% vs. 13.1%, p = 0.036) as an indication for cesarean delivery. Birth weight was significantly higher (by 200 g) in the study group. When stratified by parity, significant differences in cesarean delivery rates were observed only among nulliparous women. Logistic regression analysis showed that GDM significantly increased the risk of emergency cesarean delivery (adjusted odds ratio 1.9, 95% confidence interval 1.03-3.5, p = 0.039) only among nulliparous women, adjusted for age, body mass index, and gestational weight gain. CONCLUSION: The incidence of emergency cesarean delivery increased significantly among nulliparous GDM pregnant women, compared with that in normal pregnant women.

Adverse Maternal and Neonatal Outcomes in Adolescent Pregnancy.

STUDY OBJECTIVE: To investigate the outcomes of adolescent pregnancy. DESIGN: Retrospective cohort study from the Consortium on Safe Labor between 2002 and 2008. SETTING: Twelve clinical centers with 19 hospitals in the United States. PARTICIPANTS: Nulliparous women (n = 43,537) younger than 25 years of age, including 1189 younger adolescents (age ≤ 15.9 years), 14,703 older adolescents (age 16-19.9 years), and 27,645 young adults (age 20-24.9 years). INTERVENTIONS: Adjusted odds ratio (aOR) with 95% confidence interval (CI) were calculated, controlling for maternal characteristics and pregnancy complications (young adults as a reference group). MAIN OUTCOME MEASURES: Maternal, neonatal outcomes, cesarean indications, and length of labor. RESULTS: Younger adolescents had an increased risk of maternal anemia (aOR = 1.25; 95% CI, 1.07-1.45), preterm delivery at less than 37 weeks of gestation (aOR = 1.36; 95% CI, 1.14-1.62), postpartum hemorrhage (aOR = 1.46; 95% CI, 1.10-1.95), preeclampsia or hemolysis, increased liver enzyme levels, and low platelet syndrome (aOR = 1.44; 95% CI, 1.17-1.77) but had a decreased risk of cesarean delivery (aOR = 0.49; 95% CI, 0.42-0.59), chorioamnionitis (aOR = 0.63; 95% CI, 0.47-0.84), and neonatal intensive care unit admission (aOR = 0.80; 95% CI, 0.65-0.98). Older adolescents had an increased risk of maternal anemia (aOR = 1.15; 95% CI, 1.09-1.22), preterm delivery at less than 37 weeks of gestation (aOR = 1.16; 95% CI, 1.08-1.25), and blood transfusion (aOR = 1.21; 95% CI, 1.02-1.43), but had a decreased risk of cesarean delivery (aOR = 0.75; 95% CI, 0.71-0.79), chorioamnionitis (aOR = 0.83; 95% CI, 0.75-0.91), major perineal laceration (aOR = 0.82; 95% CI, 0.71-0.95), and neonatal intensive care unit admission (aOR = 0.89; 95% CI, 0.83-0.96). Older adolescents were less likely to have a cesarean delivery for failure to progress or cephalopelvic disproportion (aOR = 0.89; 95% CI, 0.81-0.98). For adolescents who entered spontaneous labor, the second stage of labor was shorter (P < .01). CONCLUSION: Adolescents were less likely to have a cesarean delivery. Failure to progress or cephalopelvic disproportion occurred less frequently in older adolescents. Adolescents who entered spontaneous labor had a shorter second stage of labor.

Pubic Symphysis Rupture and Separation During Pregnancy.

OBJECTIVE: The aim of this study was to determine the risk factors, clinical and radiologic criteria for diagnosis, and management of this unusual complication of pregnancy. METHODS: A PubMed and Web of Science search was undertaken with no limitations on the number of years searched. RESULTS: There were 36 publications identified, with 19 articles being the basis of this review. Multiple risk factors have been identified including multiparity, macrosomia, cephalopelvic disproportion, forceps deliveries, precipitous labor, malpresentation, prior pelvic trauma, and use of the McRoberts maneuver. The diagnosis is usually made clinically, confirmed by imaging, and considered pathological when the intrapubic gap is greater than 10 mm. Magnetic resonance imaging appears to be superior to pelvic x-ray and computed tomography scan in visualization of the bone separation. Conservative treatment remains the first choice for therapy, but women who do not respond to conservative therapy or women with large separations may need surgical stabilization with external or internal fixation. CONCLUSIONS: Widening of the pubic symphysis greater than 10 mm is pathologic. The diagnosis is clinical and confirmed by imaging studies, with magnetic resonance imaging being the superior technique. Conservative treatment is the first line of therapy. Failure of conservative therapy is treated by surgical stabilization.

Risk factors and perinatal outcome of pregnancies complicated with cephalopelvic disproportion: a population-based study.

OBJECTIVES: To characterize risk factors and perinatal outcome following cephalopelvic disproportion (CPD). METHODS: A retrospective population-based study comparing all singleton deliveries of women with and without CPD, between 1988 and 2010, was conducted. A multiple logistic regression model was used to control for confounders. RESULTS: Out of 242,520 patients, 0.3% (n = 673) were diagnosed with CPD. Using a multivariable analysis, the following obstetric risk factors were significantly associated with CPD: fetal macrosomia (birth weight above 4 kg, OR = 3.3, 95% CI 2.7-4.1, P < 0.001), infertility treatment (OR = 2.6, 95% CI 1.8-3.8, P < 0.001), previous caesarean delivery (OR = 2.2, 95% CI 1.9-2.7, P < 0.001), maternal obesity (OR = 2.1, 95% 1.3-3.4, P < 0.001), and polyhydramnios (OR = 1.7, 95% CI 1.3-2.3, P < 0.001). Deliveries complicated by CPD resulted in Caesarean delivery in 99%, and were more likely to have laceration of the cervix (1.2 vs. 0.3%, P < 0.001), rupture of uterus (0.4 vs. 0.1%, P < 0.001), intrapartum mortality (0.6 vs. 0.1% in control, P < 0.001), and low 1-min Apgar scores (<7; 27.2 vs. 6.5%, P < 0.001). CONCLUSIONS: In our population, independent risk factors for CPD include fetal macrosomia, infertility treatment, previous caesarean delivery, maternal obesity and polyhydramnion. These pregnancies had higher rates of adverse perinatal outcomes and accordingly high index of suspicion should be pursued when commencing trial of labor of such pregnancies.

Identificación de factores de riesgo más frecuentes en embarazadas cuyos partos fueron atendidos desde enero hasta diciembre 2006: en el Hospital Rural Tipo 1 Coloncito estado Táchira / Identification of risk factors more common in pregnant women whose births were attended from January to December 2006 in the Rural Hospital type 1 Coloncito Tachira

El control pre-natal (CPN) es el conjunto de acciones y procedimientos destinados a la prevención, diagnóstico y tratamiento de los factores que puedan condicionar morbimortalidad materna y perinatal. La mayoría de los modelos de CPN actualmente en uso en el mundo no han sido sometidos a una evaluación científica rigurosa para determinar su efectividad. En los países en desarrollo la implementación de los programas de CPN ha sido deficiente, con visitas clínicas irregulares, con largos tiempos de espera y mala respuesta en el cuidado de las mujeres, lo cual no constituye una excepción en nuestro país ni en el caso específico de nuestro estado y del centro asistencial tomado para el estudio. Debido a la gran preocupación que esta situación representa, surge la necesidad de realizar una rigurosa revisión de las historias clínicas de las madres cuyos partos fueron atendidos en esta institución en el 2006, así como buscar respaldo en bibliografías, manuales y publicaciones para identificar los factores de riesgo (FR) más frecuentes en dichas madres y proponer estrategias sencillas de prevención, detección temprana y manejo de los mismos, entendiendo que de nosotros como personal de salud depende hacer el embarazo un estado fisiológico femenino y no una enfermedad de nueve meses.

Determining the sensitivity of sitting height in predicting cephalo pelvic disproportion in Eritrea.

To determine the sensitivity of sitting height in predicting cephalo pelvic disproportion (CPD), a prospective case-control study was conducted. A total of 724 primiparas who delivered in Mekane Hiwot Maternity Hospital, Asmara, Eritrea were studied. Primiparas who delivered by caesarian section because of CPD were taken as cases (221), and primiparas who delivered vaginally were taken as controls (503). Height was measured for all, while sitting and while standing. The sensitivity of sitting height in predicting CPD was 34.1% (95% confidence interval [CI] = 27.7-40.3%), while that of the standing height was 33.5% (95% CI = 27.1-39.84). CPD cannot be predicted accurately by height in general and by sitting height in particular. Therefore, in order to avoid obstetric complications, all pregnant women should have access to skilled attendance during delivery and access to facilities with emergency obstetric care when needed.

Magnetic resonance imaging pelvimetry and the prediction of labor dystocia.

OBJECTIVE: To study whether magnetic resonance imaging (MRI) pelvimetry has the ability to identify those women who require cesarean delivery for labor dystocia. METHODS: From July 2003 to April 2004, nulliparous women scheduled for a labor induction for prolonged pregnancy (42 weeks) were asked to participate in a pelvimetry study. Those who consented underwent fast-acquisition MRI that included two 90-second acquisitions to evaluate fetal biometry and volumetry and maternal pelvimetry, including novel measurements of pelvic bony and soft tissue volumes as determined by MRI. Information about each patient's pregnancy, labor course, and neonatal outcome was prospectively collected. Pelvimetry results for those women undergoing operative delivery for labor dystocia were compared with those who did not. Single fetal and maternal pelvic measurements, as well as ratios of both, were analyzed. In addition, previously described radiographic pelvimetry techniques and formulas to predict dystocia were used. RESULTS: One hundred one women underwent MRI, and 22 of these underwent cesarean delivery for dystocia. No single fetal measurement was statistically associated with dystocia. Several maternal pelvic measures, fetal-to-maternal ratios, and previously reported pelvimetric techniques were significantly associated with dystocia. The ratio of magnetic resonance (MR) fetal head volume to pelvic soft tissue volume had statistical significance (P = .04). Receiver operator characteristic curves were developed for the different measurements, ratios, and formulas studied to assess whether any of the techniques could accurately predict labor dystocia requiring operative delivery. The area under the curve values ranged from 0.6 to 0.8, with the ratio of MR head volume to pelvic soft tissue being 0.7. These values suggest that MRI can identify those women at greatest risk for dystocia, but it cannot with accuracy predict which ones will require a cesarean. CONCLUSION: We found significant associations with MRI pelvimetry and labor dystocia, but MRI was not a significant improvement over previously described pelvimetric techniques. LEVEL OF EVIDENCE: II-3.