前置胎盘附着位置与剖宫产子宫切口选择

在剖宫产术前可通过病史资料和影像学检查来了解前置胎盘附着位置,而剖宫产术中直视所见虽是最终诊断,但却是滞后的诊断,故其只能作为对术前评估不足的补充。剖宫产术是前置胎盘终止妊娠的主要方式,而选择子宫切口沿着胎盘边缘相比必须打洞穿过胎盘组织取胎者的母源性失血和新生儿贫血发生率显著降低。对不同前置胎盘的患者的术式选择应个别对待,根据超声胎盘定位及术中评估等制定个体化手术方案,只要选对子宫的切口,尽量避免胎盘开窗,可有效减少母儿不良预后。     

前置胎盘患者再次剖宫产术中发生产后出血的15例临床病例分析

目的:总结既往处理经验,结合文献复习,摸索针对前置胎盘患者施行再次剖宫产术的更好的临床路径。方法:回顾分析1999年1月至2011年12月在我院产科行再次剖宫产术中合并前置胎盘和产后出血的15例患者的临床资料。患者年龄26～43岁;既往有2次剖宫产史者2例,1次者13例;终止妊娠孕周为30～40周。15例患者中产前B超提示前置胎盘者12例,其中孕期或产前有阴道出血症状者9例。手术按常规步骤进行。结果:(1)15例患者中13例为完全性前置胎盘,胎盘主体位于前壁者8例、后壁者7例;2例为边缘性前置胎盘。胎盘完全或部分粘连者13例,其中9例存在不同程度的胎盘植入,1例胎盘部分直接侵入膀胱;(2)术中平均出血量2564ml(400～12500ml),中位出血量1100ml。11例患者术中发生休克,3例患者继发弥漫性血管内凝血(DIC)。出血后采取促宫缩剂治疗及手术方法,包括局部缝合开放的血窦,缝扎子宫动脉下行支,填塞宫纱,Blynch缝合及子宫次全切除术。2例术中同时行膀胱修补术;(3)13例患者术中止血成功,2例术后加行双侧子宫动脉栓塞术。患者预后均良好。结论:前次剖宫产史的患者如合并前置胎盘、胎盘粘连或植入,术前、术中和术后都极易并发大出血,应引起临床医生的重视。     

Placenta previa associated with severe bleeding leading to hospitalization and delivery: a retrospective population-based cohort study

Introduction: The aim of our study was to compare maternal and neonatal outcomes in women with placenta previa complicated with severe bleeding leading to hospitalization until delivery versus those without severe bleeding episodes.

Methods: This is a population-based retrospective cohort study including all pregnant women with placenta previa who delivered at our medical center in the study period, divided into the following groups: 1) women with severe bleeding leading to hospitalization resulting with delivery (n?=?32); 2) patients with placenta previa without severe bleeding episodes (n?=?1217).

Results: Out of all women with placenta previa who delivered at our medical center, 2.6% (32/1249) had an episode of severe bleeding leading to hospitalization and resulting with delivery. The rate of anemia was lower (43.8% versus 63.7%, p?=?0.02) while the need for blood transfusion higher (37.5% versus 21.1%, p?=?0.03) in the study group. The rate of cesarean sections was significantly different between the groups, and a logistic regression model was constructed in order to find independent risk factors for cesarean section in our patients.

Conclusion: To the best of our knowledge, this is the first study to evaluate the impact of severe bleeding on the outcome of pregnancies complicated with placenta previa. Our study demonstrates that, in women with placenta previa, severe bleeding does not lead to increased adverse maternal or neonatal outcomes.     

胎盘异常的磁共振成像改变特征

胎盘异常可导致严重的产科并发症,仅依靠临床症状及实验室检查难以做出准确诊断,需要影像学检查辅助诊断。随着磁共振成像（magnetic resonance imaging,MRI）技术的不断发展,MRI越来越多的被应用于胎盘异常的诊断之中。文章通过阐述MRI检查方法及异常胎盘在MRI检查中的特征性表现,明确MRI的诊断价值。     

Optimal timing of antenatal corticosteroids in women with bleeding placenta previa or low-lying placenta*

Background: Administrating a single course of antenatal corticosteroids to women at risk of preterm birth between 24 and 34 weeks of gestation has been shown to decrease neonatal morbidity and mortality. There is evidence that the optimal timing for the administration of antenatal corticosteroids is within 1–7 days before birth as the effect of antenatal corticosteroids has been shown to decline 7 days after administration. Therefore, given that antenatal corticosteroids are the single most effective intervention in cases of preterm birth, efforts should be made to optimize the timing of administration of antenatal corticosteroids.

Objective: To test the hypothesis that the timing of antenatal corticosteroids in women with vaginal bleeding due to placenta previa or low-lying placenta can be optimized by identifying women at low risk of imminent delivery.

Study design: This was a retrospective cohort study of all women admitted to a tertiary referral center at 24–34 weeks’ gestation with vaginal bleeding due to placenta previa or low-lying placenta between 2003 and 2014. Multivariable logistic regression analysis was used to identify factors that are independently associated with delivery within 14 days from admission.

Results: A total of 202 women who met the inclusion criteria were admitted with vaginal bleeding in the presence of placenta previa or low-lying placenta during the study period, of whom 31 (15.3%) and 44 (21.8%) gave birth within 7 and 14 days from admission, respectively. The following factors were independently associated with delivery within 14 days from admission: complete placenta previa (odds (OR) 3.57, 95%CI 1.57–9.03), severe bleeding at presentation (OR 17.14, 95%CI 2.92–100.70), uterine contractions at presentation (OR 6.02, 95%CI 1.91–19.00), and cervical length <25?mm at presentation (OR 6.33, 95%CI 1.37–29.11). A predictive test based on the presence of ≥1 of these risk factors was associated with a sensitivity of 90.9% and a negative predictive value of 94.6% for delivery within 14 days of presentation.

Conclusions: In women presenting with vaginal bleeding due to placenta previa or low-lying placenta, it seems possible to identify a subgroup of women in whom the likelihood of delivery within 14 days is low. This information may allow for selective (rather than routine) administration of antenatal corticosteroids in this scenario, and may thereby contribute to the optimization of the timing of administration of antenatal corticosteroids.     

磁共振成像技术在凶险型前置胎盘评估中的应用价值

凶险型前置胎盘指继发于剖宫产后覆盖子宫瘢痕的前置胎盘。其胎盘植入发生率高,是导致产前、产时、产后严重出血的主要原因之一。以往超声检查一直作为诊断前置胎盘及胎儿产前筛查的首选方法,而近年来随着磁共振成像（MRI）技术的发展,MRI检查越来越多地应用到胎儿的产前检查中,特别在超声诊断不明确或诊断困难时,MRI具有独特的优势。未来的趋势将逐渐朝向功能性MRI发展。胎盘MRI检查将成为胎盘疾病诊断中一个非常重要且不可或缺的方法。     

Random placenta margin incision for control hemorrhage during cesarean delivery complicated by complete placenta previa: a prospective cohort study

Introduction: Complete placenta previa (CPP) is one of the most problematic types of abnormal placenta, which is further complicated by placenta accreta or percreta that can unexpectedly lead to catastrophic blood loss, infection, multiple complications, emergency hysterectomy, and even death. The present study aimed to assess the efficacy of random placenta margin incision in controlling intraoperative and total blood loss during cesarean section for CPP women.

Methods: A prospective cohort study, including a total of 100 consecutive pregnant women with CPP, was performed at a tertiary university-affiliated medical center between March 2016 and July 2017. All of them underwent random placenta margin incision, and intraoperative and total blood loss were analyzed. Through antenatal diagnosis using color Doppler, women were further divided into abnormally invasive placenta (AIP) and non-AIP groups, and anterior and posterior placenta groups. The protocol was registered with the Clinical Trial Registry under registration number NCT02695069.

Results: Mean maternal age and gestational age at delivery were 32.26?±?5.03 years old and 36.21?±?2.07 weeks, respectively. Total duration of the surgical procedure time was 52.50 (42.43–64.00) min. Median estimated intraoperation blood loss was 746.43 (544.44–1092.86) ml. Total blood loss was 875.00 (604.50–1196.67) ml, and 38 (38.0%) had post-partum hemorrhage. The change from baseline in the median hemoglobin level was ?0.33 (6.00–13.20). No women underwent hysterectomy due to massive hemorrhage during the study period. No women had an intraoperative urinary bladder injury, postoperative wound infection, and required relaparotomy, owing to intra-abdominal bleeding. The median hospitalization time was 5.41 (4.18–7.58) d.

Conclusion: The random placenta margin incision may be a potentially valuable surgical procedure to control the volumes of intraoperative and postoperative blood loss and reduce the incidence of postpartum hemorrhage among women with complete placenta previa.     

Marginal sinus placenta previa is a different entity in placenta previa: A retrospective study using magnetic resonance imaging

Objective

The current definition of placenta previa does not include whether the placental edge is parenchyma or marginal sinus defined as placenta previa in which the placental marginal sinus just reached the internal os and/or in which the placental parenchyma might be located at > 2 cm from internal os.

Antenatal diagnosis of placenta previa accreta in patients with previous cesarean scar

AIM: To determine the accuracy of transabdominal and transvaginal gray-scale and color Doppler in diagnosing placenta previa accreta in patients with previous cesarean sections. METHODS: Twenty-one patients who had undergone previous cesarean sections and were confirmed to have partial or total placenta previa in the current pregnancy were subjected to ultrasound examinations after the 28th week of gestation. Specific ultrasound features were looked for on gray-scale ultrasound and color Doppler examination of the placenta and its interphase with the uterus and the bladder. RESULTS: Seven of the 21 patients had ultrasound evidence of placenta accreta and all were later confirmed to have placenta previa accreta intraoperatively. The gray-scale positive findings were present in six out of the seven patients. The most prominent gray scale feature to suggest placenta accreta was the presence of multiple lakes that represent dilated vessels extending from the placenta through the myometrium. All seven patients had features of placenta accreta when examined with color Doppler. The most prominent color Doppler feature present in all seven patients was the presence of interphase hypervascularity with abnormal vessels linking the placenta to the bladder. The sensitivity and specificity of antenatal ultrasound diagnosis of placenta previa accreta was 100%. CONCLUSION: Antenatal diagnosis of placenta previa accreta can be made with a thorough ultrasound examination of the placenta in patients with previous cesarean scar and placenta previa.     

Attempted vaginal versus planned cesarean delivery in 195 breech first twin pregnancies

BACKGROUND: To compare neonatal and maternal outcomes for breech first twins according to whether vaginal or cesarean delivery was planned and to verify that in appropriate selected cases, attempted vaginal delivery is a reasonable choice. METHODS: A retrospective study of all twin pregnancies with the first twin in breech position and gestational age at least 35 weeks at birth at two French university hospital centers from January 1994 through December 2000. The primary outcome was a combined indicator of neonatal mortality and severe morbidity, as defined by one or more of the following: death before discharge, admission to neonatal intensive care unit, 5-minute Apgar score <7, cord blood pH <7.10, or birth trauma. RESULTS: Cesarean delivery was planned for 71 (36.4%) patients, and attempted vaginal delivery for 124 (63.6%), 59 (47.6%) of whom were delivered vaginally and 65 (52.4%) by cesarean during labor. Neither the combined negative outcome indicator nor neonatal mortality differed significantly for either twin or either group. There were no significant differences in maternal mortality or morbidity between the two groups. The frequency of deep vein thrombophlebitis or pulmonary embolism requiring anticoagulant therapy was significantly higher in the planned cesarean group [3/71 (4.2%) versus 0/124; p=0.047]. CONCLUSION: When appropriate criteria are used to decide mode of delivery, a careful intrapartum protocol is followed, and an experienced obstetrician, midwife, and anesthesiologist are in attendance, attempted vaginal delivery is a reasonable option for first twins in breech position.     

帆状胎盘血管前置和胎盘边缘血窦破裂的诊断及处理

帆状胎盘血管前置和胎盘边缘血窦破裂是引起妊娠晚期出血不可忽视的原因。尤其是帆状胎盘血管前置血管破裂,临床表现与前置胎盘相似,但常因胎儿失血而导致较高的围生儿死亡率。对帆状胎盘血管前置和胎盘边缘血窦破裂尽早做出诊断对降低围产期母儿风险具有重要意义。     

Cervical varix accompanied by placenta previa in twin pregnancy

BACKGROUND: Uterine cervical varix is a rare complication in pregnant women and can be the cause of obstetric hemorrhage in the vagina resulting in adverse events for both the mother and fetus. CASE: A 34-year-old Japanese woman was hospitalized at 18 weeks gestation because of cervical varix and placenta previa. Prophylactic tocolysis successfully controlled the obstetric hemorrhage. At 27 weeks gestation, emergent cesarean section was performed because of intractable hemorrhage from the marginal placenta previa. Intraabdominal findings revealed no vascular malformation of the uterus, and the operation was performed uneventfully. A speculum examination of the vagina and cervix at 1 month postpartum were unremarkable. CONCLUSION: It is important to recognize the clinical features and available treatments for cervical varix.     

低置胎盘的分娩方式探讨

目的:探讨低置胎盘的合理分娩方式。方法:选取2012年1月1日至2014年4月30日在我院分娩的单胎头位低置胎盘产妇650例。按是否试产将患者分为试产组和选择性剖宫产组;按分娩前最后一次超声胎盘下缘距离宫颈内口的距离将患者分为低置胎盘1组(下缘距内口≥0mm但20mm)、低置胎盘2组(下缘距内口≥20mm但40mm)和低置胎盘3组(下缘距内口≥40mm但70mm)。分析患者的阴道试产成功率、试产失败原因、产后出血量及分娩期并发症。结果:(1)试产组的试产总成功率为82.64%,低置胎盘1、2、3组的阴道试产成功率分别为62.5%、82.61%和84.65%,其中因产前出血而改行剖宫产的风险分别为31.25%、8.7%和1.49%;(2)低置胎盘1组患者中阴道试产和选择性剖宫产的产后出血量无显著差异[(590.94±382.79)ml vs(465.68±367.83)ml];低置胎盘2组和3组中阴道试产的产后出血量明显少于剖宫产组[(267.17±104.47)ml vs(388.10±205.61)ml,P0.0001]及[(293.00±263.731)ml vs(348.59±98.68)ml,P0.0001]。结论:胎盘下缘距宫颈内口≥20mm不应作为孕妇选择性剖宫产的手术指征。     

A comparative study of neonatal outcomes in placenta previa versus cesarean for other indication at term

Abstract

Objective: Currently, no ACOG guidelines address the issue of the optimal timing of delivery in placenta previa. Though there is an increased risk of neonatal morbidity and mortality when electively delivered preterm, it is unclear whether adverse neonatal outcomes exist when these pregnancies make it beyond term. By comparing neonatal outcomes amongst pregnancies with placenta previa versus those from cesarean for another indication at term, the objective of this study was to determine whether placenta previa is an independent risk factor for adverse neonatal outcomes at term.

Methods: We conducted a population-based cohort-study using the CDC’s Linked Birth–Infant Death data from the United States. The effect of placenta previa on the risk of adverse neonatal outcomes was estimated using unconditional logistic regression analysis, adjusting for relevant confounders.

Results: Our cohort consisted of 3?550?842 deliveries meeting inclusion criteria. The incidence of placenta previa at term was 1.3/1000 (n?=?4,492), accounting for 40.6% of all previa cases. Relative to cesareans for other indications, pregnancies with placenta previa had an increased risk of IUGR 3.20 [2.50–4.10], SGA 2.70 [2.45–2.97], respiratory distress 3.82 [2.91–5.00], prolonged ventilation 3.41 [2.70–4.32] and neonatal anemia 6.87 [4.43–10.65]. Rates of meconium aspiration syndrome, seizures, birth injury and overall infant mortality do not appear to be affected by this condition.

Conclusion: Relative to cesareans for other indications, placenta previa is associated with increased morbidity, but not mortality, at term. This information might be helpful in the development of future guidelines, which are currently needed to guide and standardize clinical practice regarding the optimal timing of delivery in placenta previa.     

经阴道三维超声微泡造影与增强磁共振对胎盘前置状态中孕引产患者胎盘植入诊断价值研究

目的 探讨经阴道三维超声微泡造影与增强磁共振检查对胎盘前置状态中孕引产孕妇胎盘植入的诊断价值.方法 选取2018年1月至2019年12月河南省人民医院48例中孕胎盘前置状态且要求引产的孕妇,均行经阴道三维超声微泡造影检查、增强磁共振检查.比较两种检查方法对中孕胎盘前置状态合并胎盘植入诊断的灵敏度、特异度、假阳性率(误诊...     

中央性前置胎盘并发胎盘植入59例临床分析

目的:探讨中央性前置胎盘并发胎盘植入的高危因素及围生期处理。方法:回顾性分析2000年1月~2009年12月四川大学华西第二医院产科收治的896例中央性前置胎盘患者(其中59例并发胎盘植入)的临床资料。结果:(1)我院近10年来中央性前置胎盘的发生率为2.26%(896/39726),中央性前置胎盘中并发胎盘植入的发生率为6.58%(59/896);(2)中央性前置胎盘并发胎盘植入的高危因素包括:孕妇年龄≥35岁、流产次数≥2次、剖宫产史;(3)中央性前置胎盘并发胎盘植入者产时产后出血量明显多于未并发胎盘植入者(2χ=70.944,P=0.000),并发胎盘植入者平均出血量高达2846.19m l;(4)所有中央性前置胎盘并发胎盘植入者均采用手术治疗,其中子宫切除率为25.42%(15/59),保守性手术为局部缝扎、局部切除、宫腔填塞、B-Lynch缝合和子宫动脉结扎等,而未并发胎盘植入者子宫切除率为0.96%(8/837)。结论:(1)对高龄的、有剖宫产史或多次流产史的中央性前置胎盘患者应警惕并发胎盘植入;(2)为减少中央性前置胎盘并发胎盘植入因严重的产时产后出血对母儿造成的危害,强调终止妊娠前的充分准备;(3)治疗上保守性手术和子宫切除都很重要。