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。     

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。     

持续性枕后位100例临床分析

目的 探讨持续性枕后位分娩方式及对母婴的影响。方法 采用回顾性分析方法，对2003年1月-2006年12月在我院住院分娩的100例持续性枕后位（枕后位组）和100例枕前位（枕前位组）的临床资料进行比较和分析。结果 枕后位组宫口扩张延缓、胎头下降延缓、胎头下降停滞、第二产程延长发生率明显高于枕前位组，差异均有显著性（P〈0．05）。枕后位组阴道助产、剖宫产、软产道裂伤、产后出血、胎儿宫内窘迫、新生儿窒息发生率均明显高于枕前位组，差异有显著性（P〈0．05）。两组骨盆临界狭窄、潜伏期延长、活跃期延长发生率比较，差异无显著性（P〉0．05）。结论 持续性枕后位母婴并发症增加，严密观察分析产程，及时诊断和处理并选择最佳分娩方式可减少母婴并发症的发生。     

活跃期枕后位胎儿脊柱位置与分娩结局的关系

目的 探讨产程中活跃期枕后位胎儿脊柱位置与分娩结局的关系. 方法 本研究为回顾性研究.2008年5月1日至2011年10月31日在解放军第四五八医院分娩的足月单胎妊娠初产妇,其胎儿体重＜4000 g,均为头先露、枕后位,共288例.在试产过程中宫口扩张4～5 cm并已破膜时,征得孕妇及家属同意,行B超检查胎头及脊柱位置,并动态观察至分娩结束.采用独立样本t检验和x 2检验对分娩结局进行分析. 结果 288例中,胎儿脊前位202例,脊后位86例.脊前位组新生儿窒息发生率低于脊后位组[1.5％(3/202)与8.1％(7/86),x2=7.97,P＜0.01].脊后位组86例分娩中胎儿均为持续性枕后位,其中4例以枕后位经阴道分娩(包括产钳助产2例).脊前位组和脊后位组产程中不同宫口扩张程度时因持续性枕后位行剖宫产终止妊娠的比例差异有统计学意义[宫口扩张6 cm:4.0％ (8/202)与36.0％(31/86),x2=53.04;7 cm:3.5％(7/202)与18.6％(16/86),x2=18.81;8 cm:1.5％(3/202)与10.5％(9/86),x2=12.18;9 cm:0.5％(1/202)与5.8％(5/86),x2=8.63;开全:1.5％(3/202)与15.1％(13/86),x2=21.36;开全1h:0.5％(1/202)与9.3％(8/86),x2=15.45;P均＜0.01].徒手旋转胎位均在宫口扩张5～6 cm时进行.脊后位组2例徒手旋转胎位均未成功.脊前位组202例中,155例未行手旋转胎位而在继续试产中胎头转为枕前位经阴道分娩,12例经徒手旋转胎位至枕前位经阴道分娩,余35例均行剖宫产终止妊娠,其中23例手术指征为持续性枕后位. 结论 产程中活跃期枕后位胎儿脊柱位置与分娩结局有密切关系,活跃期及时了解枕后位胎儿脊柱位置,可帮助医师及时采取合理分娩方式,以降低母婴并发症,提高产科质量.     

预防性干预矫正枕后位对产程的影响

持续性枕后位是造成头位难产的首要原因,手术率高,处理不当对母婴危害大。近年,其发生率有上升趋势。为提高分娩质量和阴道分娩率,将难产转化为顺产,我们对150例产妇在产程中给予预防性干预,使枕后位转至枕前位娩出,减少了持续性枕后位的发生。现报道如下。1　资料与方法11　临床资料　选择1996年8月至1999年5月在我院经Ｂ超诊断为枕后位先兆临产至潜伏期的初产妇300例,随机分为研究组及对照组各150例,两组产妇年龄均在20～30岁,孕37～41 3周,单胎头位,无严重并发症及合并症,按头位分娩评分表[1]评估骨盆胎儿体重均7分,无明显头盆不称及其它…     

持续性枕横位和枕后位病例的产程特点及影响

目的探讨持续性枕横位和枕后位的产程特点及对母儿结局的影响。方法回顾性分析64例持续性枕横位和51例持续性枕后位病例的各阶段产程时间、异常产程及产道损伤、产后出血、羊水粪染(Ⅱ°以上)、新生儿Apgar评分(5min评分≤7分)等情况,并与同期100例枕前位病例进行对比分析。结果持续性枕横位和枕后位的异常产程发生率、产道损伤、产后出血率均较对照组明显增加(P<0.05);羊水粪染及新生儿窒息发生率均较对照组明显增加,两组比较差异均有统计学意义(P<0.05)。结论重视对持续性枕横位和枕后位的早期诊断和及时处理对减少母儿并发症有重要意义。     

再谈持续性枕后位北大核心CSCD

持续性枕后位发病率为5％～12％,易出现母儿并发症。体格检查联合超声检查可提高其诊断准确率。临产前、第一产程中大部分枕后位可自行转为枕前位分娩。第二产程若出现持续性枕后位,应预防性徒手旋转胎方位;若出现胎心监护异常或第二产程延长,需立即旋转胎头、器械助产或剖宫产终止妊娠。     

再谈持续性枕后位

持续性枕后位发病率为5%~12%,易出现母儿并发症。体格检查联合超声检查可提高其诊断准确率。临产前、第一产程中大部分枕后位可自行转为枕前位分娩。第二产程若出现持续性枕后位,应预防性徒手旋转胎方位;若出现胎心监护异常或第二产程延长,需立即旋转胎头、器械助产或剖宫产终止妊娠。     

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。     

202例纠正枕横(后)位的临床探讨

目的探讨改变体位结合徒手旋转胎头在胎方位异常时的临床意义。方法选择2010年10月至2012年5月202例单胎头位,枕横(后)位无严重合并症、并发症的产妇,将其分为研究组102例,在首次发现胎方位异常时采取改变体位,待宫口开大>6cm、胎先露>S+1手转胎头;对照组100例,发现胎方位异常时采取改变体位并严密观察产程进展。结果研究组阴道分娩率(96.08%vs83%)明显高于对照组,差异有高度统计学意义(P<0.01)。产程时间缩短[(400±65)minvs(504±98)min]、经阴道分娩的产妇产后出血≥300ml者研究组较对照组明显减少(0%vs6.02%)、软产道裂伤减少(30.61%vs54.22%)、新生儿窒息率降低(1.96%vs50%),差异均有统计学意义(P<0.05)。结论改变体位结合徒手旋转胎头可使枕横(后)位致产程异常者转化为成功的阴道分娩,阴道分娩率明显升高,产程时间缩短,母儿合并症、并发症发生率明显降低。     

Shock management in acute fetomaternal hemorrhage

Abstract

The determination of fetal head position can be useful in labor to predict the success of labor management, especially in case of malpositions. Malpositions are abnormal positions of the vertex of the fetal head and account for the large part of indication for cesarean sections for dystocic labor. The occiput posterior position occurs in 15–25% of patients before labor at term and, however, most occiput posterior presentations rotate during labor, so that the incidence of occiput posterior at vaginal birth is approximately 5–7%. Persistence of the occiput posterior position is associated with higher rate of interventions and with maternal and neonatal complications and the knowledge of the exact position of the fetal head is of paramount importance prior to any operative vaginal delivery, for both the safe positioning of the instrument that may be used (i.e. forceps versus vacuum) and for its successful outcome. Ultrasound (US) diagnosed occiput posterior position during labor can predict occiput posterior position at birth. By these evidences, the time requested for fetal head descent and the position in the birth canal, had an impact on the diagnosis of labor progression or arrested labor. To try to reduce this pitfalls, authors developed a new algorithm, applied to intrapartum US and based on suitable US pictures, that sets out, in detail, the quantitative evaluation, in degrees, of the occiput posterior position of the fetal head in the pelvis and the birth canal, respectively, in the first and second stage of labor. Authors tested this computer system in a settle of patients in labor.     

Associated factors and outcomes of persistent occiput posterior position: A retrospective cohort study from 1976 to 2001.

OBJECTIVE: To identify maternal and fetal risk factors associated with persistent occiput posterior position at delivery, and to examine the association of occiput posterior position with subsequent obstetric outcomes. METHODS: This is a retrospective cohort study of 30 839 term, cephalic, singleton births. Women with persistent occiput posterior (OP) position at delivery were compared to those with occiput anterior (OA) position. Demographics, obstetric history, and labor management were evaluated and subsequent obstetric outcomes examined. Potential confounding variables were controlled for using multivariate logistic regression analysis. RESULTS: The overall frequency of OP position was 8.3% in the study population. When compared to Caucasians, a higher rate of OP was observed among African-Americans (OR = 1.4, 95% CI 1.25-1.64) while no other racial/ethnic differences were noted. Other associated factors included nulliparity, maternal age > or =35, gestational age > or =41 weeks, and birth weight >4000 g, as well as artificial rupture of the membranes (AROM) and epidural anesthesia (p < 0.001 for all). Persistent OP was associated with increased rates of operative vaginal (OR = 4.14, 95% CI 3.57-4.81) and cesarean deliveries (OR = 13.45, 95% CI 11.94-15.15) and other peripartum complications including third or fourth degree perineal lacerations (OR = 2.38, 95% CI 2.03-2.79), and chorioamnionitis (OR = 2.10, 95% CI 1.81-2.44). CONCLUSION: Epidural use, AROM, African-American ethnicity, nulliparity, and birth weight >4000 g are associated with persistent OP position at delivery, with higher rates of operative deliveries and obstetric complications. This information can be useful in counseling patients regarding risks and associated outcomes of persistent OP position.     

Influence of persistent occiput posterior position on delivery outcome.

OBJECTIVE: To evaluate the influence of intrapartum persistent occiput posterior position of the fetal head on delivery outcome and anal sphincter injury, with reference to the association with epidural analgesia. METHODS: We conducted a prospective observational study of 246 women with persistent occiput posterior position in labor during a 2-year period, compared with 13,543 contemporaneous vaginal deliveries with occiput anterior position. RESULTS: The incidence of persistent occiput posterior position was significantly greater among primiparas (2.4%) than multiparas (1.3%; P <.001; 95% confidence interval 1.4, 2.4) and was associated with significantly higher incidences of prolonged pregnancy, induction of labor, oxytocin augmentation of labor, epidural use, and prolonged labor. Only 29% of primiparas and 55% of multiparas with persistent occiput posterior position achieved spontaneous vaginal delivery, and the malposition was associated with 12% of all cesarean deliveries performed because of dystocia. Persistent occiput posterior position was also associated with a sevenfold higher incidence of anal sphincter disruption. Despite a high overall incidence of use of epidural analgesia (47% versus 3%), the institutional incidence of persistent occiput posterior position was lower than that reported 25 years ago. CONCLUSION: Persistent occiput posterior position contributed disproportionately to cesarean and instrumental delivery, with fewer than half of the occiput posterior labors ending in spontaneous delivery and the position accounting for 12% of all cesarean deliveries for dystocia. Persistent occiput posterior position leads to a sevenfold increase in the incidence of anal sphincter injury. Use of epidural analgesia was not related to the malposition.     

Maternal Temperature Elevation and Occiput Posterior Position at Birth Among Low‐Risk Women Receiving Epidural Analgesia

Introduction: To evaluate the relationship between maternal temperature elevation and occiput posterior position at birth as well as the association of fetal head position and temperature elevation on method of birth among women receiving epidural analgesia. Methods: We conducted a secondary analysis of data from the Fetal Orientation during Childbirth by Ultrasound Study (FOCUS), which used serial ultrasounds to evaluate the effect of epidural anesthesia on fetal position at birth in low‐risk women. The current analysis was limited to the 1428 study participants who received epidural analgesia. Results: In our population, 47% (n = 669) of women had a maximum intrapartum temperature greater than or equal to 99.6°F (37.6°C). The prevalence of fetal occiput posterior position at admission did not differ between women who later developed temperature elevations (24.4%) and those who did not (23.6%, P= .70). Women who developed an elevated temperature greater than or equal to 99.6°F (37.6°C) had an increased risk of occiput posterior fetal head position at birth regardless of the amount of temperature elevation (odds ratio [OR]= 2.0; 95% confidence interval [CI], 1.5‐2.8); the association persisted after control for potentially confounding factors (adjusted OR = 1.5; 95% CI, 1.1‐2.1). The cesarean birth rate among women with both temperature elevation and occiput posterior position at birth was more than 12 times the rate of women with neither risk factor (adjusted OR = 12.6; 95% CI, 7.5‐21.2). Discussion: Intrapartum temperature elevation among women receiving epidural analgesia, even if only to 99.6°F (37.6°C), is associated with approximately a 2‐fold increase in the occurrence of occiput posterior fetal head position at birth. Additionally, although this observational study cannot establish causal links, our findings suggest that the relationship between epidural‐related intrapartum temperature elevation and occiput posterior position at birth could contribute to an increased cesarean birth rate among women receiving epidural analgesia for pain relief in labor.     

The association between persistent occiput posterior position and neonatal outcomes

OBJECTIVE: To examine the effect of persistent occiput posterior position on neonatal outcome. METHODS: This is a retrospective cohort study of 31,392 term, cephalic, singleton births. Women with neonates born in persistent occiput posterior position at delivery were compared to those with occiput anterior position. Women with occiput transverse position were excluded. The association between occiput posterior position and neonatal outcomes, including 5-minute Apgar scores, umbilical cord gases, meconium-stained amniotic fluid, meconium aspiration syndrome, birth trauma, admission to the intensive care nursery, and length of stay were examined using chi(2) and Student t tests. Potential confounders (maternal age, ethnicity, parity, gestational age, epidural anesthesia, labor induction, length of labor, meconium, chorioamnionitis, birth weight, and year of delivery) were controlled for by using multivariable logistic regression and linear regression analyses. RESULTS: There were 2,591 (8.2%) neonates delivered in occiput posterior position of the total cohort of 31,392 deliveries. Compared with occiput anterior, neonates delivered in occiput posterior position had higher risks for adverse outcomes, including 5-minute Apgar score less than 7 (odds ratio [OR] 1.50, 95% confidence interval [CI] 1.17-1.91), acidemic umbilical cord gases (OR 2.05, 95% CI 1.52-2.77), meconium-stained amniotic fluid (OR 1.29, 95% CI 1.17-1.42), birth trauma (OR 1.77, 95% CI 1.22-2.57), admission to the intensive care nursery (OR 1.57, 95% CI 1.28-1.92), and longer neonatal stay in the hospital (OR 2.69, 95% CI 2.22-3.25). CONCLUSION: Persistent occiput posterior position at delivery is associated with higher risks of adverse neonatal outcomes compared with neonates delivered in the occiput anterior position. This information may be important in counseling women who experience persistent occiput posterior position in labor. Level of Evidence: II-2.     

Associated factors and outcomes of persistent occiput posterior position: A retrospective cohort study from 1976 to 2001

Objective. To identify maternal and fetal risk factors associated with persistent occiput posterior position at delivery, and to examine the association of occiput posterior position with subsequent obstetric outcomes.

Methods. This is a retrospective cohort study of 30 839 term, cephalic, singleton births. Women with persistent occiput posterior (OP) position at delivery were compared to those with occiput anterior (OA) position. Demographics, obstetric history, and labor management were evaluated and subsequent obstetric outcomes examined. Potential confounding variables were controlled for using multivariate logistic regression analysis.

Results. The overall frequency of OP position was 8.3% in the study population. When compared to Caucasians, a higher rate of OP was observed among African-Americans (OR = 1.4, 95% CI 1.25–1.64) while no other racial/ethnic differences were noted. Other associated factors included nulliparity, maternal age ≥35, gestational age ≥41 weeks, and birth weight >4000 g, as well as artificial rupture of the membranes (AROM) and epidural anesthesia (p < 0.001 for all). Persistent OP was associated with increased rates of operative vaginal (OR = 4.14, 95% CI 3.57–4.81) and cesarean deliveries (OR = 13.45, 95% CI 11.94–15.15) and other peripartum complications including third or fourth degree perineal lacerations (OR = 2.38, 95% CI 2.03–2.79), and chorioamnionitis (OR = 2.10, 95% CI 1.81–2.44).

Conclusion. Epidural use, AROM, African-American ethnicity, nulliparity, and birth weight >4000 g are associated with persistent OP position at delivery, with higher rates of operative deliveries and obstetric complications. This information can be useful in counseling patients regarding risks and associated outcomes of persistent OP position.     

Dystocia in late labor: determining fetal position by clinical and ultrasonic techniques

A failure of adequate progression during late labor occurs often and may prohibit an accurate determination of the fetal head position from scalp edema or caput formation. This investigation was undertaken to determine whether ultrasonic evaluation could confirm or correct the digital examination impressions of the fetal head position. Eighty-six attempted vaginal deliveries had recent evidence for arrested cervical dilation after 7 cm or more. An occiput transverse position in 24 (28%) cases was diagnosed accurately, with the need for additional ultrasonic information only in the presence of scalp edema. Distinguishing between a persistent occiput posterior (15 cases, 17%) or anterior (47 cases, 55%) position was often inexact by palpation alone. Combined clinical and ultrasonic impressions allowed for a significantly more precise diagnosis. Ultrasonic imaging allowed for more security while waiting, more confidence with midforceps application, or a prompter decision for cesarean section, depending on the head position.     

Risk factors for forceps delivery in nulliparous patients

OBJECTIVE: To identify risk factors for forceps delivery during first pregnancy. MATERIALS AND METHODS: A retrospective case-control study was carried out in a tertiary maternity ward between January 2001 and December 2003. A total of 582 nulliparous women, with full-term (>37 weeks gestation), singleton, cephalic pregnancies, who delivered by the vaginal route with or without instrumental assistance were evaluated. RESULTS: The strongest risk factors for forceps delivery were birth weight greater than 4000 g (OR: 6.5; 95% CI: 1.6, 26.9), the occiput posterior position of the fetal head (OR: 5.8; 95% CI: 2.5, 13.8), and epidural analgesia (OR: 7.7; 95% CI: 4.1, 14.7). Other significant risk factors for forceps delivery were age over 35 years (OR: 2.4; 95% CI: 1.1, 5.1), induction of labor (OR: 2.1; 95% CI: 1.4, 3.1), first stage of labor longer than 420 min (OR: 2.3, 95% CI: 1.3,4.2), and a prolonged second stage of labor (OR: 1.6, 95% CI: 1.1, 2.4). CONCLUSION: Age over 35 years and induction of labor are risk factors for forceps delivery at admission. Epidural use, fetal head in occiput posterior position, and birth weight >4000 g are strong intrapartum risk factors for instrumental delivery in nulliparous women.