Indication and Post-operative Complication of Primary Caesarean Section in Multiparous Women in A Tertiary Level Hospital.

The spectrum of indications for primary caesarean section changes with advancing parity. As parity advances more cesarean section are done for maternal rather than fetal indications. The objective of this study was to determine the indications and complications of caesarean section in multiparous women with history of previous vaginal delivery. This cross-sectional descriptive observational study was conducted in Mymensingh Medical College Hospital from January 2019 to June 2019 among 100 purposively selected multiparous women who underwent primary caesarean section. A well-designed, semi-structured questionnaire was used to collect data by face-to-face interview, clinical examinations and laboratory investigations. Data analysis was conducted in SPSS 20.0 version. Majority (74.0%) of the women in this study were in the age group 21-30 years with mean age of 26.3±5.76 years. Majority of the patients were of second gravida (42.0%) followed by third gravida (33.0%). The highest gravida in this study was 6th. Most of the patients were of para 1(44.0%). Highest para in this study was para 5. The most common indication of caesarean section in this study was foetal distress (26.0%). The next common indications were cephalo-pelvic disproportion (22.0%), antepartum haemorrhage (13.0%), mal-presentaion or mal-position (16.0%). Other causes were PROM (8.0%), prolonged labour (6.0%), cord prolapse (2.0%), post-dated pregnancy (4.0%), severe pre-eclampsia (2.0%) and secondary subfertility (1.0%). There was no case of maternal mortality in this study but 15 mothers suffered from various post-operative complications like wound infection (4.0%), UTI (4.0%), puerperal pyrexia (3.0%), postpartum haemorrhage (3.0%) and paralytic ileus (1.0%). Among the babies delivered 97 were live births. Among the 97 live births 11(11.34%) were preterm babies. Among the babies delivered majority (85.0%) was with good APGAR score (7-10). In conclusion it can say that a multiparous women in labour requires the same attention as that of primigravida. A parous women needs good obstetric care to improve maternal and neonatal outcome and still keeping caesarean section to a lower rate.

Neonatal head circumference to maternal mid-transverse pelvic distance ratio as a key anatomical predictor for dystocia: Retrospective case-control study.

OBJECTIVE: This study aimed to examine maternal and neonatal factors in cesarean deliveries due to dystocia, including cephalopelvic disproportion, latent-phase prolongation, and fetal malposition or malpresentation. Additionally, we sought to compare the differences between the dystocia subgroups. METHOD AND MATERIALS: This retrospective case-control study included women who delivered between January 2010 and June 2021 after 37 weeks of pregnancy and underwent abdominal-pelvic CT scans within 5 years before and after delivery. Neonatal factors were extracted from medical charts immediately after delivery. RESULTS: Among the 292 women studied, those with cesarean deliveries for dystocia were older (mean ± SD, 34.2 ± 4.27 vs. 32.2 ± 3.8, p-value = 0.002), had higher pre-pregnancy BMI (22.7 ± 3.67 vs. 21.4 ± 3.48, p-value = 0.012) and term-BMI (27.4 ± 3.72 vs. 25.9 ± 3.66, p-value = 0.010), shorter interspinous distance (ISD, the distance between ischial spine) (10.8 ± 0.76 vs. 11.2 ± 0.85 cm, p-value = 0.003), and longer head circumference (HC) (35 ± 1.47 vs. 34.4 ± 1.36 cm, p-value = 0.003) compared to those who had vaginal deliveries. Univariate logistic regression for dystocia revealed associations between HC/maternal height and HC/ISD ratios (OR, 2.02 [95% confidence interval, CI, 1.4 ~ 2.92], 12.13 [3.2 ~ 46.04], respectively). Multivariate logistic analysis indicated that maternal age, ISD, and HC were significant factors for dystocia (OR, 1.11 [95% CI, 1.01 ~ 1.21], 0.49 [0.26 ~ 0.91], 1.53 [1.07 ~ 2.19], respectively). The subgroup with latent-phase prolongation exhibited the lowest birthweight/term-BMI ratio (124 ± 18.8 vs. 113 ± 10.3 vs. 134 ± 19.1, p-value = 0.013). CONCLUSION: The HC/ISD ratio emerged as a crucial predictor of dystocia, suggesting that reducing term-BMI could potentially mitigate latent-phase prolongation. Further research assessing the maternal mid-pelvis during pregnancy and labor is warranted, along with efforts to reduce BMI during pregnancy.

The second stage of labor.

The second stage of labor extends from complete cervical dilatation to delivery. During this stage, descent and rotation of the presenting part occur as the fetus passively negotiates its passage through the birth canal. Generally, descent begins during the deceleration phase of dilatation as the cervix is drawn upward around the fetal presenting part. The most common means of assessing the normality of the second stage of labor is to measure its duration, but progress can be more meaningfully gauged by measuring the change in fetal station as a function of time. Accurate clinical identification and evaluation of differences in patterns of fetal descent are necessary to assess second stage of labor progress and to make reasoned judgments about the need for intervention. Three distinct graphic abnormalities of the second stage of labor can be identified: protracted descent, arrest of descent, and failure of descent. All abnormalities have a strong association with cephalopelvic disproportion but may also occur in the presence of maternal obesity, uterine infection, excessive sedation, and fetal malpositions. Interpretation of the progress of fetal descent must be made in the context of other clinically discernable events and observations. These include fetal size, position, attitude, and degree of cranial molding and related evaluations of pelvic architecture and capacity to accommodate the fetus, uterine contractility, and fetal well-being. Oxytocin infusion can often resolve an arrest or failure of descent or a protracted descent caused by an inhibitory factor, such as a dense neuraxial block. It should be used only if thorough assessment of fetopelvic relationships reveals a low probability of cephalopelvic disproportion. The value of forced Valsalva pushing, fundal pressure, and routine episiotomy has been questioned. They should be used selectively and where indicated.

The Anterior Pelvic Index (API) in the Classification of the Female Pelvis and Prediction of Fetopelvic Disproportion / El Índice Pelviano Anterior (API) en la Clasificación de la Pelvis Femenina y Predicción de la Desproporción Fetopélvica

SUMMARY: Measurements of the upper strait of the pelvis can be calculated using the Anterior Pelvic Index. The objective of the study was to determine the external validity and cut-off point of the API, to classify narrow pelvises from normal ones. We selected 214 women from 15 to 55 years old, 171 had vaginal delivery and 43 by caesarean section by feto-pelvic disproportion (FPD) of maternal origin, in whom the API was calculated, of which its mean difference was established with an alpha error of <0.05. Maximum values of sensitivity and specificity, ROC curve and Youden index were determined. The student's t gave a p-value =0.000 of the mean difference between the women who had vaginal delivery and those who had cesarean section by FPD of maternal origin; the value of the area under the ROC curve was 0.758 (CI 95% 0.695 - 0.814) with a p-value=0.0001. Maximum sensitivity was 74.42 % (CI 95%: 58.8 % to 86.5 %) and maximum specificity was 73.10 % (CI 95%: 65.8 % to 79.6 %), produced a Youden index of 0.475 (CI 95% 0.283 - 0.590) which is associated with the 15.44 (CI 95% 14.19 - 15.83) of the API scale. The API is a good tool for predicting women with suspected narrow pelvis and allows its classification into three types of pelvises: an API value of more than 15.83 would indicate pelvis suitable for vaginal delivery; an API value between 14.19 and 15.83 would be suspected of pelvic narrowness; an API value less than 14.19 would confirm a narrow pelvis.

Las medidas del estrecho superior de la pelvis pueden calcularse mediante el Índice Pelviano Anterior. El objetivo del estudio fue determinar la validez externa y el punto de corte del API, para clasificar pelvis estrechas de las normales. Seleccionamos 214 mujeres de 15 a 55 años, 171 tuvieron parto vaginal y 43 mediante cesárea por DFP de origen materno, en quienes se calculó el API, del cual se estableció su diferencia de medias con un error alfa de <0,05. Se determinaron valores máximos de sensibilidad y especificidad, curva ROC e índice de Youden. La t de Student dio un p-valor=0,000 de la diferencia de medias entre las mujeres de tuvieron parto vaginal y las que fueron sometidas a cesárea por DFP de origen materno; el valor del área bajo la curva ROC fue 0,758 (IC 95% 0,695 - 0,814) con un p- valor=0,0001. La máxima sensibilidad (74,42 %. IC 95%: 58,8 % a 86,5 %) y máxima especificidad (73,10 %. IC 95%: 65,8 % a 79,6 %), produjeron un índice de Youden de 0,475 (IC 95% 0,283 - 0,590) el cual está asociado al valor 15,44 (IC 95% 14,19 - 15,83) de la escala del API. El API es una buena herramienta de predicción de mujeres con sospecha de pelvis estrecha y permite su clasificación en tres tipos de pelvis: un valor de API de mas de 15,83 indicaría pelvis aptas para un parto vaginal; un valor de API entre 14,19 y 15,83 se sospecharía de estrechez pélvica; un valor de API menor a 14,19 confirmaría una pelvis estrecha.

Head circumference, as predictor of cephalopelvic disproportion: A prospective analysis of cases of spontaneous vaginal delivery and caesarean section in Ekiti State, Nigeria.

Cephalopelvic disproportion (CPD) is a previously undiagnosed anatomical misfit between maternal pelvis and the fetal head. It is one of the major indications for cesarean section (CS), especially in sub-Saharan Africa. Early diagnosis, could avert events that can increase maternal and perinatal morbidity and mortality associated with this condition. This study was designed to determine the mean head circumference of the fetus in relation to CPD as an indicator for caesarean section. A total of 350 parturients who had spontaneous vaginal deliveries (group A) were compared with another 350 parturients who had cephalopelvic disproportion leading to CS (group B). The socio-demographic characteristics, delivery parameters, head circumference, fetal weight and length were recorded in a proforma and analyzed using SPSS version 21. P value was set at 0.05. The mean head circumference for the all the babies delivered in this study was 34.6 ±1.7cm. The mean head circumference of babies delivered to women with CPD via caeserean section compared to those who had vaginal delivery was significantly greater (35.15±1.5 vs 34.1±1.8, mean difference 1.9±0.1, X2,0.308 p <0.001). The cut-off for diagnosis of cephalopelvic disproportion was head circumference 34.8cm which has a specificity of about 74% and sensitivity of 88% with area under the curve being 66%. The study demonstrated that when the head circumference of a baby is 34.8cm and above, the risk of having cephalopelvic disproportion leading to a CS is high with sensitivity of 88% and specificity of about 74%.

The active phase of labor.

The active phase of labor begins at various degrees of dilatation when the rate of dilatation transitions from the relatively flat slope of the latent phase to a more rapid slope. No diagnostic manifestations demarcate its onset, other than accelerating dilatation. It ends with apparent slowing of dilatation, a deceleration phase, which is usually short in duration and frequently undetected. Several aberrant labor patterns can be detected during the active phase, including protracted dilatation, arrest of dilatation, prolonged deceleration phase and failure of descent. Underlying factors may include cephalopelvic disproportion, excessive neuraxial block, poor uterine contractility, fetal malpositions, malpresentations, uterine infection, maternal obesity, advanced maternal age and previous cesarean delivery. When an active-phase disorder is identified, cesarean delivery is justifiable if there is compelling clinical evidence of disproportion. A prolonged deceleration disorder is strongly associated with disproportion and second stage abnormalities. Shoulder dystocia may occur if vaginal delivery eventuates. This review discusses several issues raised by the introduction of new clinical practice guidelines for labor management.

Childbirth simulation to assess cephalopelvic disproportion and chances for failed labor in a French population.

Reducing failed labor and emergency cesarean section (CS) rates is an important goal. A childbirth simulation tool (PREDIBIRTH software and SIM37 platform) that evaluates a 5-min magnetic resonance imaging (MRI) assessment performed at 37 weeks of gestation was developed to enhance the consulting obstetrician's ability to predict the optimal delivery mode. We aimed to determine the potential value of this childbirth simulation tool in facilitating the selection of an optimal delivery mode for both mother and infant. A retrospective cohort study was performed on all patients referred by their obstetricians to our level 2 maternity radiology department between December 15, 2015 and November 15, 2016, to undergo MRI pelvimetry at approximately 37 weeks of gestation. The childbirth simulation software was employed to predict the optimal delivery mode based on the assessment of cephalopelvic disproportion. The prediction was compared with the actual outcome for each case. Including childbirth simulations in the decision-making process had the potential to reduce emergency CSs, inappropriately scheduled CSs, and instrumental vaginal deliveries by up to 30.1%, 20.7%, and 20.0%, respectively. Although the use of the simulation tool might not have affected the overall CS rate, consideration of predicted birthing outcomes has the potential to improve the allocation between scheduled CS and trial of labor. The routine use of childbirth simulation software as a clinical support tool when choosing the optimal delivery mode for singleton pregnancies with a cephalic presentation could reduce the number of emergency CSs, insufficiently justified CSs, and instrumental deliveries.

Effect of intimate partner violence in pregnancy on maternal and perinatal outcomes at the Korle Bu teaching hospital, Ghana: An observational cross sectional study.

OBJECTIVE: To determine the association between intimate partner violence and pregnancy outcomes. METHODS: This was a descriptive study of sociodemographic characteristics of participants, their partners and intimate partner violence. Participants' delivery records were reviewed for additional medical and obstetric information and abused women and their neonates followed until discharge. χ2 and Student t test were used to assess associations, followed by logistic regression with odds ratio (OR) and 95% confidence intervals (CI). A value of P less than 0.05 was considered statistically significant. RESULTS: The study included 270 participants of whom 84 (31.1%) reported experiencing domestic violence during pregnancy. One hundred and fourteen (42%) had experienced domestic violence pre-pregnancy and 69 (60.5%) of these women experienced further domestic violence during pregnancy. Emotional violence was commonest 80/270 (29.6%) and no sexual violence was reported. Domestic violence declined from 42% (pre-pregnancy) to 31.1% (in-pregnancy) (P = 0.009). Risk factors during pregnancy were young age (15-24 years; OR 5.8, 95% CI1.65-20.38), nulliparity (OR 3.75, 95% CI 1.90-7.41), and partner's alcohol consumption (OR 5.04, 95% CI 2.50-10.13). Associated outcomes included late prenatal booking, gestational hypertension, and cephalopelvic disproportion. CONCLUSION: We found high prevalence of domestic violence during pregnancy, preponderance of emotional abuse, and decline of physical abuse. Nulliparity, younger age, and partner's alcohol consumption predicted abuse. Late-booking, gestational hypertension, cephalopelvic disproportion, and fetal distress were associated.

Magnetic resonance imaging in late pregnancy to improve labour and delivery outcomes - a systematic literature review.

BACKGROUND: Magnetic resonance imaging (MRI) provides excellent soft tissue visualisation which may be useful in late pregnancy to predict labour outcome and maternal/neonatal birth trauma. OBJECTIVE: To study if MRI in late pregnancy can predict maternal and neonatal outcomes of labour and birth. METHODS: Systematic review of studies that performed MRI in late pregnancy or immediately postpartum. Studies were included if they imaged maternal pelvic or neonatal structures and assessed birth outcome. Meta-analysis was not performed due to the heterogeneity of studies. RESULTS: Eighteen studies were selected. Twelve studies explored the value of MRI pelvimetry measurement and its utility to predict cephalopelvic disproportion (CPD) and vaginal breech birth. Four explored cervical imaging in predicting time interval to birth. Two imaged women in active labour and assessed mouldability of the fetal skull. No marker of CPD had both high sensitivity and specificity for predicting labour outcome. The fetal pelvic index yielded sensitivities between 59 and 60%, and specificities between 34 to 64%. Similarly, although the sensitivity of the cephalopelvic disproportion index in predicting labour outcome was high (85%), specificity was only 56%. In women with breech presentation, MRI was demonstrated to reduce the rates of emergency caesarean section from 35 to 19%, and allowed better selection of vaginal breech birth. Live birth studies showed that the fetal head undergoes a substantial degree of moulding and deformation during cephalic vaginal birth, which is not considered during pelvimetry. There are conflicting studies on the role of MRI in cervical imaging and predicting time interval to birth. CONCLUSION: MRI is a promising imaging modality to assess aspects of CPD, yet no current marker of CPD accurately predicts labour outcome. With advances in MRI, it is hoped that novel methods can be developed to better identify individuals at risk of obstructed or pathological labour. Its role in exploring fetal head moulding as a marker of CPD should be further explored.

A five-year retrospective review of the maternal and feotal outcome of obstructed labour and its determinants in a tertiary hospital in Nigeria.

Background: Obstructed labour is one of the common obstetric emergencies in Nigeria which is associated with an increased maternal and foetal complications. Objective: To determine the maternal and foetal outcome of obstructed labour and its determinants in a tertiary hospital in Ebonyi State University Teaching hospital Abakaliki. Methods: A retrospective review of all women with obstructed labour managed at Ebonyi State University Teaching hospital Abakaliki between January 2007 and December 2011 was carried out. Results: The prevalence rate of obstructed labour was 3.4% (95%CI 3.37 - 3.42) for the period under review. Women in their second and third decade of life formed 91.6% (196/214) of patients in the study. Majority of obstructed labour occurred in primiparous women (92/214, 42.9%) and the commonest cause of obstructed labour was cephalopelvic disproportion (106/214, 49.6%). The commonest maternal complication was wound infection accounting for 23.2% (48/214) of all the complications. Most of the babies delivered had a good Apgar score as was noted in 60.3% (129/214) of cases. Being unbooked, para 3 and above, maternal age of 30 and above, having no formal education and rural residence were strongly associated with parturient having maternal complication (P > 0.05) and abnormal APGAR score. The maternal and perinatal mortality rate was 191/100,000 live births and 168/1000 deliveries respectively. Conclusion: The commonest cause of obstructed labour in our review is cephalopelvic disproportion occurring more in primiparous women. Wound infection is the commonest maternal complication with majority of the neonates having a good outcome. Provision of free antenatal care services, education of women on the importance of antenatal care, early presentation in the hospital and early use of broad spectrum antibiotics would help to reduce the associated complications.

Feto-maternal outcomes of caesarean delivery in Federal Medical Centre, Asaba: a two year review.

Background: The upward trend of caesarean section and its associated morbidity/mortality especially in low and middle income areas makes regular appraisal of the procedure necessary. Objective: To evaluate caesarean section; its rate, indications, and maternal and fetal outcomes in Asaba. Methods: A retrospective study of all caesarean sections carried out at the obstetrics unit of the Federal Medical Centre, Asaba, between July 1, 2018 and June 31, 2020. Data was analyzed using SPSS version 20. Results: There were 2778 deliveries during the period, out of which 705 had caesarean sections, giving an overall caesarean section rate of 25.4%.There were 456 (64.7%) emergency caesarean sections. The commonest indication for caesarean section was repeat caesarean section 196 (27.8%), while cephalo-pelvic disproportion 87 (12.3%) was the commonest indication for emergency caesarean section. Majority of the babies had low APGAR score at 1min and 5mins, 126 (27.6%) and 50 (11.0%) from emergency than elective caesarean section 16 (6.4%) and 5 (2.0%) at 1min and 5mins respectively (x2=17.963, P<0.001). There were 31 (4.2%) perinatal deaths out of which majority 28 (6.1%) were from emergency caesarean sections (x2=9.412 P=0.002). The commonest post-operative complication was postpartum anaemia (140 (19.9%) while caesarean section case fatality was 0.6%. Conclusion: This study showed a caesarean section rate of 25.4% with repeat caesarean section and Cephalopelvic disproportion being the most common indication for elective and emergency caesarean section respectively. Emergency caesarean section accounted for most of the cases and is associated with a higher risk of maternal and perinatal morbidity and mortality.

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.

Vaginal birth after cesarean section: Experience from a regional hospital.

OBJECTIVE: Trial of labor after cesarean section (TOLAC) is an option for women with previous cesarean section. However, few women choose this option because of safety concerns. We evaluate the safety and risks associated with TOLAC and the success rate of vaginal birth after cesarean delivery (VBAC). MATERIAL AND METHODS: We reviewed all patients with a history of previous cesarean section that underwent elective repeat cesarean section (ERCS) or TOLAC in a regional teaching hospital from Nov, 2013 to May, 2018. Maternal basic clinical information, intrapartum management, postpartum complications, and neonatal outcomes were analyzed. RESULTS: 199 pregnant women with a history of at least one previous cesarean section were enrolled. 156 women received ERCS and 43 women (21.6%) underwent TOLAC, with 37 (86.0%) who underwent successful VBAC. The VBAC rate was 18.6%. Higher success rate was found in women with previous vaginal birth than in women without vaginal birth (100% vs. 81.8%). One case (2.3%) in the VBAC group was complicated with uterine rupture and inevitable neonatal death during second stage of labor. The uterus was repaired without maternal complications. In another case, the newborn's condition was complicated with low APGAR score (<7) at birth due to maternal chorioamnionitis. Among indications for previous cesarean section, cephalo-pelvic disproportion (CPD) was associated with TOLAC failure and uterine rupture after VBAC. CONCLUSION: VBAC is a feasible and safe option. Modes of delivery should be thoroughly discussed when considering TOLAC for women with history of previous cesarean section due to CPD, considering its association with TOLAC failure in second stage of labor.

Magnetic Resonance Imaging-Based Nomogram to Antenatal Predict Cesarean Delivery for Cephalopelvic Disproportion in Primiparous Women.

BACKGROUND: Cephalopelvic disproportion (CPD)-related obstructed labor is associated with maternal and neonatal morbidity and mortality. Accurate prediction of whether a primiparous woman is at high risk of an unplanned cesarean delivery would be a major advance in obstetrics. PURPOSE: To develop and validate a predictive model assessing the risk of cesarean delivery in primiparous women based on MRI findings. STUDY TYPE: Prospective. POPULATION: A total of 150 primiparous women with clinical findings suggestive of CPD. FIELD STRENGTH/SEQUENCE: T1-weighted fast spin-echo sequences, single-shot fast spin-echo (SSFSE) T2-weighted sequences at 1.5 T. ASSESSMENT: Pelvimetry and fetal biometry were assessed independently by two radiologists. A nomogram model combined that the clinical and MRI characteristics was constructed. STATISTICAL TESTS: Univariable and multivariable logistic regression analyses were applied to select independent variables. Receiver operating characteristic (ROC) analysis was performed, and the discrimination of the model was assessed by the area under the curve (AUC). Calibration was assessed by calibration plots. Decision curve analysis was applied to evaluate the net clinical benefit. A P value below 0.05 was considered to be statistically significant. RESULTS: In multivariable modeling, the maternal body mass index (BMI) before delivery, bilateral femoral head distance, obstetric conjugate, fetal head circumference, and fetal abdominal circumference was significantly associated with the likelihood of cesarean delivery. The discrimination calculated as the AUC was 0.838 (95% confidence interval [CI]: 0.774-0.902). The sensitivity and specificity of the nomogram model were 0.787 and 0.764, and the positive predictive and negative predictive values were 0.696 and 0.840, respectively. The model demonstrated satisfactory calibration (calibration slope = 0.945). Moreover, the decision curve analysis proved the superior net benefit of the model compared with each factor included. DATA CONCLUSION: Our study might provide a nomogram model that could identify primiparous women at risk of cesarean delivery caused by CPD based on MRI measurements. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.

Pelvic and neonatal size correlations in light of evolutionary hypotheses.

OBJECTIVE: This study aimed to analyze the correlations between maternal size, neonatal size, and gestational variables. METHODS: Our sample comprises 131 mother-infant dyads. We investigated correlations between five neonatal traits (gestational age, birthweight, head, suboccipito-brematic, and abdominal girths), three maternal traits (height, BMI, and uterus height), and three pelvic variables (conjugate, inter-spinous diameters, and sub-pubic angle) using computed tomography pelvimetry. RESULTS: We found that the five neonatal traits were significantly intercorrelated. BMI was not correlated with neonatal traits while maternal height was correlated with birthweight, suboccipito-brematic, and abdominal girth. In the multiple regression models, gestational age was correlated with birthweight, head, and abdominal girth. Among the neonatal and pelvimetry correlations, conjugate diameter was slightly correlated with suboccipito-bregmatic girth, but inter-spinous and sub-pubic angle were not correlated with neonatal traits. Uterus height predicted all neonatal variables, but it was not correlated with gestational age. DISCUSSION: Our results suggest that fetal growth is shaped by maternal phenotype rather than external ecological factors. The association of the inlet size with suboccipito-bregmatic girth reflects the tight fit between the neonatal brain and the maternal pelvis dimensions, an adaptation that would reduce the risk of cephalo-pelvic disproportion, while the absence of tight fit at the midplane and outlet could be due to the effect of the pelvic relaxation. Uterus distention is not the only mechanism involved in the initiation of parturition. Birth and pregnancy are complex processes and we suggest that maternal-neonatal associations are the result of a combination of multiple obstetric tradeoffs.

The Relation between Head Circumference and Mid-Pelvic Circumference: A Simple Index for Cephalopelvic Disproportion Evaluation.

INTRODUCTION: Cephalopelvic disproportion (CPD) is one of the most common obstetric complications. Since CPD is the disproportion between the fetal head and maternal bony pelvis, evaluation of the head circumference (HC) relative to the maternal bony pelvis may be a useful adjunct to pre-labor CPD evaluation. The aim of the present study was a proof-of-concept evaluation of the ratio between HC and pelvic circumference (PC) as a predictor of CPD. METHODS: Of 11,822 deliveries, 104 cases that underwent an abdominopelvic CT for any medical indication and who underwent normal vaginal deliveries (NVDs) (n = 84) or cesarean deliveries (CD) due to CPD (n = 20) were included retrospectively. Maternal pelvis dimensions were reconstructed and neonatal HC, as a proxy for fetal HC, was measured. The correlation between cases of CPD and cephalopelvic circumference index (CPCI), which represents the ratio between the HC and PC in percentage (HC/PC × 100), was evaluated. RESULTS: The mid-pelvis CPCI (MP-CPCI) was larger in CD groups as compared to the NVD group: 103 ± 11 versus 97 ± 8%, respectively (p = 0.0003). In logistic regression analysis, the MP-CPCI was found to be independently associated with CD due to CPD: each 1% increase in MP-CPCI increased the likelihood of CD for CPD by 11% (adjusted odds ratio [aOR] 1.11, 95% CI, 1.03-1.19, p = 0.004). The aOR for CD due to CPD increased incrementally as the MP-CPCI increased, from 3.56 (95% CI, 1.01-12.6) at MP-CPCI of 100 to 5.6 (95% CI, 1.63-19.45) at 105, 21.44 (95% CI, 3.05-150.84) at 110, and 28.88 (95% CI, 2.3-362.27) at MP-CPCI of 115. CONCLUSIONS: The MP-CPCI, representing the relative dimensions of the fetal HC and maternal PC, is a simple tool that can potentially distinguish between parturients at lower and higher risk of CPD. Prospective randomized studies are required to evaluate the feasibility of prenatal pelvimetry and MP-CPCI to predict the risk of CPD during labor.