暂无摘要。

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.
OBJECTIVE: To develop and validate a predictive model assessing the risk of cesarean delivery in primiparous women based on MRI findings.
METHODS: Prospective.
METHODS: A total of 150 primiparous women with clinical findings suggestive of CPD.
UNASSIGNED: T1-weighted fast spin-echo sequences, single-shot fast spin-echo (SSFSE) T2-weighted sequences at 1.5 T.
RESULTS: Pelvimetry and fetal biometry were assessed independently by two radiologists. A nomogram model combined that the clinical and MRI characteristics was constructed.
METHODS: 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.
CONCLUSIONS: Our study might provide a nomogram model that could identify primiparous women at risk of cesarean delivery caused by CPD based on MRI measurements.
METHODS: 2 TECHNICAL EFFICACY: Stage 2.

To analyze the relationship between fetal head size and maternal pelvis size using magnetic resonance imaging (MRI) with a 3-D reconstruction technique.
A total of 301 nulliparous full-term Chinese pregnant women with cephalic presentation were enrolled and received MRI examinations before labor onset. Data were collected and imported into Mimics software to reconstruct the maternal pelvis and fetus.
Of 301 pregnant women, 212 underwent vaginal delivery and 32 received cesarean section. The body mass index (BMI) was significantly different between the vaginal delivery group and the suspected cephalopelvic disproportion (CPD) group; the larger the BMI, the higher was the risk of CPD. The transverse diameter of the pelvic inlet and the posterior sagittal diameter of the midpelvis were significantly larger in the vaginal delivery group, compared with the suspected CPD group. Fetal weight > 3.5 kg could be used as a diagnostic indicator for CPD.
BMI is a risk factor for CPD, and fetal weight < 3.5 kg is an important diagnostic indicator for natural delivery in Chinese pregnant women.

To explore the possible risk factors for cesarean scar pregnancy (CSP), the incidence of which is increasing rapidly in China.
79 patients with CSP and 69 non-CSP expectant mothers with at least 1 previous cesarean section were employed in the study. The obstetric histories of the participants were collected and analyzed using Chi square test.
We found that 77.2% CSP patients had ≥ 3 pregnancies and only 36.2% women had ≥ 3 pregnacies in non-CSP group. During the previous cesarean delivery, 21.5% of CSP patients had entered the first stage of labor, which was 43.5% in non-CSP group (P < 0.05). Cephalopelvic disproportion occurred in 51.9% of CSP patients, which was significantly higher than that (23.2%) in non-CSP group (P < 0.01). 11.4% of CSP patients had undergone cesarean section due to breech and shoulder presentation in the past, which was only 1.4% in non-CSP group. However, no significance was noted (P > 0.05). We did not find significant differences between the CSP and non-CSP patients in maternal age, multiple cesarean sections, gestational age, emergency or elective caesarean section.
Multiple pregnancies, absence of the first stage of labor, and cephalopelvic disproportion might be the risk factors for the occurrence of CSP.

OBJECTIVE: To describe three-dimensional (3D) magnetic resonance imaging (MRI) pelvimetry methods and to establish the pelvimetric reference in a large population of Chinese females at term pregnancy.
METHODS: Three-hundred one pregnant women at term who underwent MRI were included. Three-dimensional pelvic models were reconstructed using Mimics. 10.0 software based on MRI data sets, and measurements of these models were made. Pelvimetric results according to delivery modality were presented. Additionally, the previously described CT 3D pelvimetry method for predicting cephalopelvic disproportion (CPD) was used to validate its accuracy.
RESULTS: Two hundred ten women underwent vaginal delivery, and 13 underwent caesarean delivery for CPD. 3D modelling of the pelvis of pregnant women was feasible using MR data sets. Pelvimetric parameters in the vaginal delivery group were as follows: transverse diameter, 134.7 mm ± 7.5; obstetric conjugate, 126.9 mm ± 8.3; interspinous distance, 113.4 mm ± 8.2; sagittal midpelvis, 117.8 mm ± 8.1; intertuberous distance, 127.1 mm ± 10.4; sagittal outlet, 110.2 mm ± 8.9, and posterior sagittal outlet, 59.7 mm ± 8.1. According to the previously described CT 3D pelvimetry method for predicting CPD, 67.6% (142/210) of women in the vaginal delivery group were diagnosed with CPD.
CONCLUSIONS: 3D MR pelvimetry is a novel method for determining pelvic dimensions at term pregnancy. A prospective trial is needed to establish a useful value for predicting CPD in Chinese females at high risk of CPD.

OBJECTIVE: To study the changes of intrapartum cesarean rate, cesarean indications and pregnancy outcomes after the new partogram applied.
METHODS: Totally 3 290 pregnant women trying to vaginal delivery which were managed according to the new partogram in Beijing Obstetrics and Gynecology Hospital, Capital Medical University from August to October in 2014(new partogram group)were involved; 2 987 pregnancy women trying to vaginal delivery from May to July in 2014 which were managed according to the old partogram(old partogram group)were involved as control. The intrapartum cesarean rate, cesarean indications and the pregnancy outcomes between the two groups were analyzed.
RESULTS: The rate of intrapartum cesarean delivery was 8.50%(254/2 987)in old partogram group, and was significantly higher than that in new partogram group(6.2%, 204/3 290; P<0.01). Cesarean indications in old partogram group included 18 labor protraction(7.1%, 18/254), 82 labor arrest(32.3%, 82/254), 44 relative cephalopelvic disproportion(17.3%, 44/254), 80 fetal distress(31.5%, 80/254), 23 intrauterine infection(9.1%, 23/254)and 7 cesarean delivery on maternal request(CDMR; 2.8%, 7/254). Cesarean indications in new partogram group included 33 labor arrest(16.2%, 33/204), 71 relative cephalopelvic disproportion(34.8%, 71/204), 73 fetal distress(35.8%, 73/204)and 22 intrauterine infection(10.8%, 22/204), 5 CDMR(2.5%, 5/204). There were no significant differences in incidence of asphyxia neonatorum and puerperal morbidity(P> 0.05), but the incidence of postpartum hemorrhage in new partogram group was higher than the old partogram group[6.9%(14/204)versus 1.6%(4/254), P<0.05].
CONCLUSIONS: After the new partogram applied, the rate of intrapartum cesarean delivery is significantly decreased, but the incidence of postpartum hemorrhage is increased.

OBJECTIVE: To estimate cesarean delivery rates and indications by region in mainland China.
METHODS: A cross sectional survey of all deliveries in 39 hospitals in 14 provinces of mainland China from January 1 to December 31, 2011 was evaluated for mode of delivery, cesarean delivery rates and indications for delivery.
RESULTS: (1) A survey of a total of 112 138 women at delivery with gestations greater than 24 weeks was analyzed. 79 631 and 32 507 deliveries were obtained from the tertiary and secondary hospitals respectively. 90 971 were primipara, 21 167 were multipara. Of these pregnancies, 61 084, 49 734 and 1 320 cases resulted in cesarean delivery, vaginal delivery and operative vaginal delivery respectively, the cesarean delivery rate was 54.472% (61 084/112 138). Among 61 084 women who had cesarean delivery, 14 998 cases of the cesarean deliveries were performed without medical indications, 46 086 cases of the cesarean deliveries had medical indications. The cesarean delivery rate of the tertiary hospitals was 55.927% (44 535/79 631), and was significant higher than that in the secondary hospitals (50.909%, 16 549/32 507; P < 0.01). (2) Overall 24.553 % (14 998/61 084) of cesarean deliveries were performed without medical indications. 19.744% (8 793/44 535) of the cesarean deliveries without medical indications were performed in the tertiary hospitals, and was significant lower than in the secondary hospitals (37.495%, 6 205/16 549;P < 0.01). (3) Maternal request was the most common indication (24.553% of all cesarean deliveries), followed by fetal distress (12.507% , 7 640/61 084), cephalopelvic disproportion (11.787%, 7 200/61 084), previous uterine surgery (10.374%, 6 337/61 084), malpresentation (5.815%, 3 552/61 084), failure to progress (5.710%, 3 488/61 084) and suspected macrosomia (5.594%, 3 417/61 084).
CONCLUSIONS: The increasing caesarean section rate in mainland China is explained mainly by the high non-indicated caesarean section rate. The main medical indications of the cesarean deliveries included fetal distress, cephalopelvic disproportion, previous uterine surgery, malpresentation and failure to progress.

BACKGROUND: The association between fetal gender and pregnancy outcomes has been thoroughly demonstrated in western populations. However, this association has not been thoroughly documented in China. The primary objective of the present study is to determine whether the association of adverse pregnancy and labour outcomes with male fetuses applies to the Chinese population.
METHODS: This cross-sectional hospital-based retrospective survey collected data from thirty-nine hospitals in 2011 in mainland China. A total of 109,722 women with singleton pregnancy who delivered after 28 weeks of gestation were included.
RESULTS: Of these pregnancies, the male-to-female sex ratio was 1.2. The rates of preterm birth (7.3% for males, 6.5% for females) and fetal macrosomia (8.3% for males, 5.1% for females) were higher for male newborns, whereas fetal growth restriction (8.0% for females, 5.4% for males) and malpresentation (4.3% for females, 3.6% for males) were more frequent among female-bearing mothers. A male fetus was associated with an increased incidence of operative vaginal delivery (1.3% for males, 1.1% for females), caesarean delivery (55.0% for males, 52.9% for females), and cephalopelvic disproportion/failure to progress (10.0% for males, 9.2% for female). Male gender was also significantly associated with lower Apgar scores (<7 at 5 min, adjusted odds ratio 1.3, 95% CI 1.0-1.6), as well as a neonatal intensive care unit admission and neonatal death, even after adjustments for confounders (adjusted odds ratio 1.3, 95% CI 1.1-1.5, adjusted odds ratio 1.4, 95% CI 1.1-1.8).
CONCLUSIONS: We confirm the existence of obvious neonatal gender bias and adverse outcomes for male fetuses during pregnancy and labour in our population. Further research is required to understand the mechanisms and clinical implications of this phenomenon.