分娩期综合性干预预防持续性枕后位的研究

目的研究产程不同时相干预预防持续性枕后位的措施，以降低持续性枕后位的发生率，改善分娩结局。方法将９６例枕后位产妇随机平均分为两组，对研究组的产妇施行针对产程不同时相的一系列干预措施，包括人工破膜、纠正异常胎轴、产妇采取与胎背同侧的高坡侧俯卧位、徒手扩张宫颈及徒手旋转胎头。结果研究组活跃期及第二产程较对照组短，研究组活跃期先露下降平均速度及宫口扩张平均速度均快于对照组，研究组的持续性枕后位发生率及胎儿窘迫发生率均低于对照组，产后出血量少于对照组（Ｐ＜０．０５）。结论综合性干预措施安全、有效、易行。     

持续性枕横位及枕后位的产程特点及围产儿预后

目的：探讨持续性枕横位及枕后位的产程特点及围产儿预后。方法：采用回顾性资料分析方法，对１９９５年１１月至１９９６年７月在我院分娩的持续性枕横位及枕后位孕妇的临床资料进行分析。并与同期枕位正常的９０例（对照组）孕妇进行比较。结果：枕位异常者，胎儿体重过大、宫缩乏力的比例明显增加，产程各期时间均明显延长，胎先露下降速度明显减慢，各产程异常发生率明显增加，手术产率明显增加。枕横位总手术产率为８２．８１％，枕后位为９２．３１％，胎儿宫内缺氧、新生儿窒息率明显增加。结论：持续性枕横位及枕后位是难产的主要原因之一，若处理不当，围产儿预后欠佳。     

宫缩图对识别头位难产的价值

对６０例单胎、头先露，正式临产需手术助产分娩的初产妇及６０例单胎，头先露，正式临床经阴道自然分娩的初产妇的宫缩图进行分析。结果表明：研究组宫缩图的类型平行型及多交叉型多于对照组（Ｐ〈０．０５），对照组宫缩图的类型单交叉型显著多于研究组（Ｐ〈０．０５），研究组宫缩图第一交叉出现至胎儿娩出时间及至产程图交叉的时间均明显长于对照组（Ｐ〈０．０５）；研究组第一交叉出现时宫颈口扩张明显小于对照组（Ｐ〈０．０     

42例剖宫产子宫切口撕裂的临床分析与防治

目的：探讨剖宫产子宫切口撕裂的原因及防治措施。方法：回顾性分析2006年1月-2011年12月行子宫下段剖宫产术612例病历资料。结果：子宫下段横切1：2撕裂42例,发生率6．86％。产妇第二产程、持续性枕后位、胎头深固者（先露≥3cm）、体重大于≥4000的胎儿、子宫下段形成差者切口撕裂率高。结论：娩头困难是造成术中子宫切口撕裂的主要原因,医生熟练掌握剖宫产的指征,恰当把握手术时机,才能有效避免剖宫产子宫切口裂伤的发生。     

持续性枕后位的临床特点及分娩方式选择

目的探讨持续性枕后位的临床特点及分娩方式。方法采用回顾性分析方法，对1998年1月至2004年12月在重庆医科大学两所附属医院住院分娩的112例持续性枕后位（枕后位组）和112例枕前位（枕前位组）的临床资料进行分析，比较两组产程情况、分娩方式及母儿结局。结果两组头位分娩评分、第一产程、第二产程及总产程时间比较，差异有显著性意义（P〈0．05）。枕后位组产钳助产、剖宫产、会阴裂伤、产后出血、胎儿窘迫、新生儿窒息率等均明显高于枕前位组，差异均有显著性意义（P〈0．05）。枕后位组宫口扩张及胎头下降延缓和第二产程延长的发生率均高于枕前位组，差异均有显著性意义（P〈0．05）。剖宫产组富口扩张延缓、胎头下降停滞和第二产程延长的发生率明显高于阴道分娩组（P〈0．05）。而剖宫产组和阴道分娩组骨盆临界狭窄、潜伏期及活跃期延长的发生率比较，差异无显著性意义（P〉0．05）。结论持续性枕后位导致母儿并发症增加，及时处理并选择最佳分娩方式可减少母儿并发症的发生。     

新式剖宫产382例临床分析

目的 评价新式剖宫产术式的优点。方法 分析３８２例新式剖宫产产妇术中、术后情况,并与同期上剖宫产及子宫下段剖宫产比较,观察手术时间、出血量、娩头难易、术后进食时间及排气时间等。结果 新式剖宫产较腹膜外剖宫产从开腹到娩胎儿时间平均缩短１０．１ｍｉｎ（Ｐ〈０．０１）,出血量平均减少２８ｍｌ（Ｐ〈０．０５）,且娩胎头容易,较子宫下段剖」宫产手术时间平均缩短１２ｍｉｎ（Ｐ〈０．０１）,术后进食平均早１１．     

米索前列醇用于足月妊娠引产的临床观察

目的：探讨米索前列醇用于足月妊娠引产的安全性及效果。方法：将６０例有引产指征的孕足月单胎头位、无宫缩的初产妇，随机分成两组，研究组（３０例）用米索前列醇５０μｇ阴道用药，每３小时１次至正式临产；对照组（３０例）用蓖麻油鸡蛋餐口服。结果：两组引产总有效率无显著差异，研究组引产时间显著少于对照组（Ｐ＜０．０５），研究组需静脉滴注催产素人数为１０．０％，显著少于对照组的４０．０％，（Ｐ＜０．０５），用药６小时后研究组宫颈评分提高５．５分，对照组提高３．１分，评分结果比较，差异有显著性（Ｐ＜０．０５），研究组子宫收缩过频的发生率为１６．７％，对照组为３．０％。结论：阴道放置米索前列醇用于足月妊娠引产能促宫颈成熟及发动子宫收缩，是安全、有效的引产方法     

调整宫缩后侧俯卧位纠正持续性枕横位枕后位的观察

目的：探讨侧俯卧位对于纠正持续性枕横位和持续性枕后位的效果,降低临床产妇的剖宫产率。方法：以我院2012年1—2013年5月于我院分娩的98例持续性枕横位和持续性枕后位产妇为对象,采取缩宫素调整宫缩后指导其以侧俯卧位来纠正,并记录相关临床资料。结果：对98例持续性枕横位和持续性枕后位产妇纠正后经阴道自然分娩者73例,占74．49％;产钳助产11例,占11．22％;纠正不成功而进行剖宫产者14例,占14．29％;新生儿均健康,产妇也未发生严重的并发症。结论：侧俯卧位对于调整宫缩后持续性枕横位和持续性枕后位纠正效果显著,能有效的降低剖宫产率,值得在临床上推广。     

胎轴与头位难产关系的研究

根据体表标志，设计胎轴尺，以此测量异常胎轴并对此进行分度。结果：妊娠晚期的５１２例中，胎轴异常者１０８例，占２１．１％，其中重度为５１．８％；分娩期的４８３例中，胎轴异常８８例，均为重度，占１８．２％。８８例又随机分为两组：对照组３０例，研究组５８例，研究组行手法矫正。结果：研究组胎头下降加速，产程缩短，持续性枕后或枕横位发生率及手术产率降低，产后出血量减少。与对照组比较，差异有显著性。提示：妊娠晚期及产时，胎轴异常对分娩过程有一定影响，及时发现和矫正，对减少产力消耗和降低难产发生率有一定临床意义。     

初产妇头位分娩100例产程图分析

对５０例头位难产的初产妇（异常组）及５０例头位顺产的初产妇（对照组）的产程图进行分析。结果表明：异常组潜伏期、活跃期时限明显大于对照组（Ｐ＜０．００１），宫颈扩张速度和胎头下降速度都明显小于对照组（Ｐ＜０．００１）。异常组产后出血量、总产程、手术产率、新生儿窒息率都明显高于对照组（Ｐ＜０．００１）。异常组５０例中，经过积极处理后，有３８例阴道分娩，占７６％。提示：产程中应用产程图对发现产程异常、指导产程处理和识别难产具有非常重要的意义。     

两种体侧卧位法纠正枕后位的临床观察

目的探讨产程中产妇采用两种不同体侧卧位纠正枕后位的临床效果.方法选择潜伏期经内诊或B超确诊为枕后位的初产妇100例,按随机表法分成同侧卧位组和对侧卧位组(各50例),分别采用同侧和对侧卧位法纠正胎方位,观察两组阴道分娩率、第1产程时间.结果(1)同侧卧位组阴道分娩34例(68%),胎儿转至枕前位27例(54%),对侧卧位组阴道分娩为22例(44%),胎儿转至枕前位12例(24%),两组比较,差异有显著性(P＜0.005).(2)同侧卧位组平均第1产程时间为(13.5±6.5)h;对侧卧位组平均第1产程时间为(17.1±7.2)h,两组比较,差异有极显著性(P＜0.01).结论产程中指导产妇取同侧卧位矫正枕后位,是提高阴道分娩率、缩短第1产程的有效方法.     

Breech presentation after cesarean section: always a section?

A retrospective review of 71 breech deliveries after previous cesarean was done to determine the need for repeat cesarean section. Twenty-four (33.8%) women were allocated to the elective repeat cesarean section group and forty-seven (66.2%) patients were allocated to a trial of labor group. Thirty-seven (78.7%) were delivered of their infants vaginally. A total of 37 of the 71 women (52.1%) had successful vaginal deliveries. Neonatal morbidity did not differ for women who were delivered vaginally or by cesarean section. Maternal febrile morbidity was significantly higher in the cesarean section group than in the vaginal delivery group (p less than 0.001). On the basis of these data, a trial of labor seems reasonable in carefully selected cases of breech presentation after a previous cesarean section.     

Influence of the pelvic outlet capacity on fetal head presentation at delivery

The influence of pelvic outlet capacity on fetal head presentation in 1,402 term primiparas with normal pregnancies was studied. In all cases radiological pelvimetry was carried out and labor started spontaneously. Occiput posterior (OP) delivery occurred in 5.1%. As pelvic outlet capacity decreased an increased frequency of OP presentations and need for epidural anesthesia (EDA) was found. With OP presentation the duration of labour was longer, the frequency of EDA, instrumental delivery, cesarean section and low Apgar score at 1 minute were all higher, all compared with occiput anterior (OA) presentation. No difference in fetal morbidity was found. When the influence of the pelvic outlet capacity was eliminated through comparison of matched groups, the course of delivery became more similar whether the presentation was OA or OP and the frequency of EDA became the same. Reduced pelvic outlet capacity seemed to be one cause of both OP presentation and the use of EDA.     

Singleton vaginal breech delivery at term: still a safe option

OBJECTIVE: To examine the obstetric and perinatal outcome of pregnancies with singleton breech presentation at term when selection for vaginal delivery was based on clear prelabor and intrapartum criteria. METHODS: The outcomes of all pregnancies with a breech presentation after 37 weeks of gestation were retrospectively reviewed from January 1997 to June 2000. Criteria for prelabor cesarean or trial of vaginal breech delivery included type of breech, estimated fetal weight (more than 3,800 g), maternal preference, and gestation more than 41 weeks. An intrapartum protocol excluded induction and oxytocin augmentation of labor, combined with a low threshold for cesarean delivery for dystocic labor; an experienced obstetrician was in attendance during labor and delivery. RESULTS: Of 641 women, 343 (54%) underwent prelabor cesarean, and 298 (46%) had a trial of vaginal delivery, of whom 146 (49%) delivered vaginally. Significantly fewer nulliparas (58 of 158, 37%) than multiparas (88 of 140, 63%; P <.001) achieved vaginal delivery after trial of labor. Significantly more infants weighing more than 3,800 g were selected for prelabor (87 of 343, 25%) and intrapartum (31 of 152, 20%) cesarean than delivered vaginally (15 of 146, 10%). Two neonates (0.7%) had Apgar scores of less than 7 at 5 minutes; both were neurologically normal at 6 weeks. There were no nonanomalous perinatal deaths and no cases of significant trauma or neurological dysfunction; 3 infants delivered vaginally died due to lethal anomalies. CONCLUSION: Safe vaginal breech delivery at term can be achieved with strict selection criteria, adherence to a careful intrapartum protocol, and with an experienced obstetrician in attendance. Our protocol effectively selects larger infants for cesarean delivery. LEVEL OF EVIDENCE: II-2     

Impact on delivery outcome of ultrasonographic fetal head position prior to induction of labor

OBJECTIVE: To assess clinical and sonographic fetal head position before induction of labor, position at delivery, and whether occiput posterior (OP) position is associated with adverse delivery outcome. METHODS: Abdominal palpation and ultrasonographic fetal head and spine position were determined at 36 weeks or more of gestation in 289 women immediately before induction of labor and the head position at delivery noted. Chi-square, Mann-Whitney U tests, and logistic regression were used to assess whether OP position was associated with cesarean delivery. RESULTS: Ninety-seven (36%) of 270 women with full outcome data had an OP position on ultrasonography before induction of labor. Of these 97 women, eight (8%) were OP at delivery. Sixty-eight percent of the 25 OP positions at delivery occurred due to a mal-rotation from a non-OP position during labor. Logistic regression showed that OP position before induction of labor was not an independent predictor of cesarean delivery (odds ratio 1.75, 95% confidence interval 0.97-3.15, P=.06). CONCLUSION: Two thirds of OP positions at delivery after induction of labor occur due to a mal-rotation in labor from a non-OP position. Ultrasonography is an easy method of assessing fetal head position before induction of labor. In clinical practice, its usefulness is limited by the fact that, contrary to conventional teaching, OP position before induction of labor does not appear to be associated with an increased risk of cesarean delivery. LEVEL OF EVIDENCE: II.     

Antepartum detection of cord presentation by transvaginal ultrasonography for term breech presentation: potential prediction and prevention of cord prolapse

AIM: We evaluated the efficacy of antepartum screening for cord presentation by trans-vaginal ultrasonography (TVS) on predicting and preventing umbilical cord prolapse (UCP) in term breech delivery. METHODS: We investigated every woman with a breech-presenting fetus for cord presentation by weekly TVS after 36 weeks of gestation since 1995. If the cord was found in advance of fetal presenting parts, we recommended her to undergo elective cesarean section to avoid UCP. We studied the incidence of cord presentation by TVS and the clinical courses of the cases with it for 198 women who delivered breech after 36 weeks from 1995 to 2005 (group A). Further, the incidence of UCP was compared between group A and another 230 women who delivered breech at term from 1983 to 1994 (group B). RESULTS: Cord presentation was detected by TVS at least once in eight (4%) group A patients. Seven of them underwent elective cesarean section and, in six of these (86%), cord presentation was still found at the time of operation. The eighth patient became free of cord presentation at the later examinations and delivered vaginally without UCP. A hundred and twenty-one (61%) women in group A and 159 (69%) women in group B delivered vaginally. No UCP occurred in group A, while it occurred in 10 (4%) cases of group B (P < 0.01), and one baby died of it. CONCLUSIONS: Detection of cord presentation by TVS has a potential to predict and reduce UCP in breech delivery at term.     

Clinical significance of the floating fetal head in nulliparous women in labor

OBJECTIVE: To examine the course of labor in nulliparous women in active labor with a floating fetal head. STUDY DESIGN: A prospective, cohort study of nulliparous women presenting in active labor at term with a floating fetal head (station > or = -3, n = 108) or engaged fetal head (n = 241). All patients were examined by a senior physician. Assignment to the study or control group was noted in the investigator's records. However, management of labor was at the discretion of the labor ward team on duty. RESULTS: Cesarean section rates for failure to progress were significantly higher in the study group (17.1% versus 4.2%, P < .0001), and the second stage of labor was prolonged (65.3 +/- 27.1 versus 54.9 +/- 30.2 minutes, P < .03). None of the women who had a persistently floating fetal head at 7 cm of cervical dilation delivered vaginally. Birth weights were larger (P < .03) and Apgar scores lower (P < .0001) in the study group. The lengths of the active phase and instrumental delivery rates were similar in the two groups. CONCLUSION: Nulliparous women presenting in active labor at term with a floating head are at substantially increased risk of cesarean section for abnormal progress of labor. However, the majority of patients will still deliver vaginally. A persistently floating head with advanced cervical dilation (7 cm) should prompt consideration of cesarean section since little is to be gained by waiting.     

Vaginal birth after cesarean section: is suspected fetal macrosomia a contraindication?

The American College of Obstetricians and Gynecologists' "Guidelines for vaginal delivery after a previous cesarean birth" include a precautionary statement regarding estimated fetal weight of more than 4000 g. To evaluate the validity of this restriction, we conducted an analysis of the outcomes of 301 trials of labor with birth weights equal to or greater than 4000 g. In the birth-weight range of 4000-4499 g, 139 of 240 patients (58%) delivered vaginally. In the group with birth weights exceeding 4500 g, 26 of 61 patients (43%) delivered vaginally. When compared with 1475 trials of labor with birth weights under 4000 g, no significant differences in perinatal or maternal morbidity were found. Comparison with a control group of 301 women with no previous uterine surgery who delivered macrosomic infants also demonstrated no significant differences in perinatal or maternal morbidity. The medical literature does not support elective cesarean section for suspected fetal macrosomia in nondiabetic women, and based on our experience, there appears to be no reason for treating previous-cesarean mothers differently.     

Vaginal delivery in Nigerian women after a previous cesarean section

A total of 154 consecutive Nigerian women at term pregnancy who had undergone one previous cesarean delivery were prospectively studied during the year March 1987 to February 1988. A repeat elective cesarean section was performed in 52 (33.8%) patients. Vaginal delivery was achieved in 73 (71.6%) of the 102 subjects who were allowed into labor, and in over 90% of the comparison group. High vaginal delivery rates occurred among the women within the selection criteria irrespective of the indication for the previous cesarean section. A repeat emergency cesarean section was performed in 29 (24.5%) women. Rupture of the uterine scar occurred in 5 (4.9%) instances with the loss of 2 babies; there was no maternal loss. Excluding the high incidence of fetal asphyxia and uterine rupture which occurred among women in the study group, maternal morbidity and perinatal mortality and morbidity were similar to those of the comparison group. There was a statistically significant difference between the study and comparison group. There was a statistically significant difference between the study and comparison groups with regard to the mode of delivery. Among the study group, a significant correlation existed between the vaginal delivery rate of the patients and the indication for the primary cesarean section. There was however, no significant difference between the mean parities of the women who were delivered by cesarean section and those who delivered vaginally. Similarly, no significant difference existed in the mean birthweights of the babies delivered vaginally and those who were delivered abdominally during labor.(ABSTRACT TRUNCATED AT 250 WORDS)     

Randomized management of the nonfrank breech presentation at term: a preliminary report

Cesarean section has become the standard management used by many clinicians for breech presentation in labor. Proof of the superiority of routine cesarean section has been largely circumstantial. Concern over rising cesarean section rates has led to renewed interest in possible alternatives. Protocols have been developed to select which patients may be allowed a trial of labor with frank breech presentation at term. We undertook a prospective clinical trial comparing elective cesarean section with a selective management protocol for the nonfrank breech presentation at term. One hundred five patients with nonfrank breech presentations at term in labor were studied. Seventy (67%) were randomized to a trial of labor and 35 (33%) to elective cesarean section. Of the patients allowed a trial of labor, 31 (44%) were delivered vaginally, and 39 (56%) required cesarean section. The largest single cause of a "failed" trial of labor was inadequate pelvic dimensions on x-ray pelvimetry (23 patients, 59%). Neonatal morbidity assessed by Apgar scores, cord gases, birth injury, and hospital stay was not different for those delivered vaginally or by cesarean section. Maternal morbidity in terms of febrile morbidity, blood transfusion, wound infections, and hospital stay was significantly greater among women delivered by cesarean section. Two of three neonatal deaths occurred in infants with major congenital anomalies. The third infant, apparently normal, died after vaginal delivery. Extensive evaluation suggests the death was attributable to inadequate resuscitation. We conclude that the use of a selective management protocol under controlled conditions is a reasonable alternative to elective cesarean section. Approximately one half of patients allowed a trial of labor may be expected to deliver vaginally with neonatal morbidity comparable to that seen with cesarean section.