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。     

Management of occiput posterior position

A 27‐year‐old, para 1 at 40 1/7 weeks' gestation presented to the labor and delivery unit in labor. Her prenatal course was uncomplicated, and her previous obstetric history included a vaginal delivery of a full‐term 7‐pound, 9‐ounce male infant. She described her first birth as being “straightforward.” It was 10 hours in length, and she received an epidural for analgesia. Upon this admission, she stated that she had been having regular, painful contractions for the past 10 hours. Her cervix was 1 cm dilated, 50% effaced, and the fetus was at ?3 station. The membranes were intact. She was experiencing intensely painful contractions every 2 to 3 minutes, and reported severe back pain and exhaustion. Leopold's maneuvers revealed small parts on the left anterior side, and the fetal back was difficult to palpate, consistent with an occiput posterior (OP) position. Per hospital protocol, she was confined to bed rest and placed on continuous fetal and uterine monitoring. Five hours after admission, her membranes ruptured spontaneously with clear fluid. The fetus was then at ?2 station, and her cervix had dilated to 4 cm and was 80% effaced. She reported increased pain and requested an epidural, hoping to get some rest. After the epidural was placed, her contractions became irregular (every 3–10 min), and as a result, oxytocin augmentation was started. Approximately 1 hour later, the external uterine monitor began failing to record contractions, and an intrauterine pressure catheter was placed. Ten hours after admission, and 4 hours after oxytocin was started, her cervix had dilated to 7 cm. Despite several epidural boluses, she continued to experience severe back pain, and a belly binder was applied as a relief measure. Throughout her labor, she stayed in bed with position changes that were limited to left lateral and right lateral. Cervical dilatation did not progress beyond 7 cm, and no fetal descent occurred over the next 4 hours, despite progressive oxytocin augmentation and an adequate contraction pattern based on Montevideo units. The midwife collaborated with the attending obstetrician and a cesarean section was recommended for failure to progress. A healthy baby boy who was noted to be in direct OP position was born via cesarean section with Apgar scores of 9/9. He weighed 8 pounds, 10 ounces.     

The impact of occiput posterior fetal head position on the risk of anal sphincter injury in forceps-assisted vaginal deliveries

OBJECTIVE: A forceps-assisted vaginal delivery is a well-recognized risk factor for anal sphincter injury. Some studies have shown that occiput posterior (OP) fetal head position is also associated with an increased risk for third- or fourth-degree lacerations. The objective of this study was to assess whether OP position confers an incrementally increased risk for anal sphincter injury above that present with forceps deliveries. STUDY DESIGN: This was a retrospective cohort study of 588 singleton, cephalic, forceps-assisted vaginal deliveries performed at our institution between January 1996 and October 2003. Maternal demographics, labor and delivery characteristics, and neonatal factors were examined. Statistical analysis consisted of univariate statistics, Student t test, chi2, and logistic regression. RESULTS: The prevalence of occiput anterior (OA) and OP positions was 88.4% and 11.6%, respectively. The groups were similar in age, marital status, body mass index, use of epidural, frequency of inductions, episiotomies, and shoulder dystocias. The OA group had a higher frequency of rotational forceps (16.2% vs 5.9%, P = .03), greater birth weights (3304 +/- 526 g vs 3092 +/- 777 g, P = .004), and a larger percentage of white women (48.8% vs 34.3%, P = .04). Overall, 35% of forceps deliveries resulted in a third- or fourth-degree laceration. Anal sphincter injury occurred significantly more often in the OP group compared with the OA group (51.5% vs 32.9%, P = .003), giving an odds ratio of 2.2 (CI: 1.3-3.6). In a logistic regression model that controlled for occiput posterior position, maternal body mass index, race, length of second stage, episiotomy, birth weight, and rotational forceps, OP head position was 3.1 (CI: 1.6-6.2) times more likely to be associated with anal sphincter injury than OA head position. CONCLUSION: Forceps-assisted vaginal deliveries have been associated with a greater risk for anal sphincter injury. Within this population of forceps deliveries, an OP position further increases the risk of third- or fourth-degree lacerations when compared with an OA position.     

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。     

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.     

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.     

Correcting occiput posterior position during labor: the role of maternal positions

Occipito-posterior presentation represents 10 to 34% of cephalic presentations in early labor. Spontaneous rotation during labor to occipito-anterior mode occurs in most cases, but 5 to 8% of fetuses will persist in posterior position for the expulsive phase of delivery. Previous research has shown that this presentation carries an increased risk of unusually long labor, maternal and fetal exhaustion, instrument-assisted delivery, severe perineal injury, and cesarean section. The diagnosis of posterior variety is usually made quite late at the end of dilation. Several researchers have reported the benefits of determining presentation during labor by transabdominal ultrasonography. Some obstetrical techniques to correct these presentations at complete dilation have also been described. In the case of diagnosis of posterior variety, the usual attitude is expectant management. Postural techniques to promote physiological labor and delivery have been documented in the literature. De Gasquet has described a very precise technique to facilitate fetal rotation, but its effectiveness has never been assessed scientifically. A Cochrane review on the topic has shown that similar positions are well accepted by women and reduce back pain. On the other hand, the sample size of included studies appeared inadequate to assess their interest for use in childbirth, in general, and for adverse outcomes associated with posterior presentation varieties in particular. Attempts to correct the fetal malposition during the expansion phase would allow to reduce adverse outcomes during the expulsive phase of delivery. Further research is necessary to assess the efficacity of specific maternal positions during labor for the correction of fetal posterior presentation.     

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.     

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.     

Management of persistent occiput posterior position: a substantial role of instrumental rotation in the setting of failed manual rotation

Introduction: To compare the maternal and neonatal outcomes associated with Instrumental Rotation (IR) to operative vaginal delivery in occiput posterior (OP) position with Thierry’s spatulas (TS), in the setting of failed manual rotation (MR).

Study design: We led a prospective observational cohort study in a tertiary referral hospital in Toulouse, France. All women presenting in labor with persistent OP position at full cervical dilatation and who delivered vaginally after failed MR and with IR or OP assisted delivery were included from January 2014 to December 2015.

The main outcomes measured were maternal morbidity parameters including episiotomy rate, incidence and severity of perineal lacerations, perineal hematomas and postpartum hemorrhage. Severe perineal tears corresponded to third and fourth degree lacerations. Fetal morbidity outcomes comprised neonatal Apgar scores, acidemia, fetal injuries, birth trauma and neonatal intensive care unit admissions.

Results: Among 9762 women, 910 (9.3%) presented with persistent OP position at full cervical dilatation and 222 deliveries were enrolled. Of 111 attempted IR, 97 were successful (87.4%). The incidence of anal sphincter injuries was significantly reduced after IR attempt (1.8% vs. 12.6%; p?Conclusion: Our results support the use of IR in order to reduce perineal morbidity associated with OP assisted delivery, in the setting of a failed manual rotation.     

Thrombocytopenia at delivery: a prospective survey of 6715 deliveries

Thrombocytopenia occurred in 513 (7.6%) of 6715 consecutive deliveries that occurred in our hospital over a 3-year interval. The patients with thrombocytopenia could be divided into three groups. The largest group (65.1%) consisted of healthy women whose thrombocytopenia was incidentally detected. The next group of patients (13.1%) was composed of healthy women who had an obstetric or medical condition such as diabetes or premature labor. No mother or infant in either group had excessive bleeding, and no infant had a cord platelet count less than 50 x 10(9) per liter. The last group (21%) was composed of hypertensive patients and patients with immune thrombocytopenia. Two infants in this group had cord platelet counts less than 50 x 10(9) per liter, but neither had bleeding. This study indicates that incidental thrombocytopenia in an otherwise well woman at term is the most frequent type of thrombocytopenia and poses no apparent risk for mother or infant at delivery.     

Obstetric characteristics and neonatal outcome of unplanned out-of-hospital term deliveries: a prospective, case-control study

OBJECTIVE: To describe the obstetric characteristics and neonatal outcomes in unplanned out-of-hospital deliveries. STUDY DESIGN: Obstetric characteristics and neonatal outcomes were compared between 151 consecutive parturients with unplanned, out-of-hospital term deliveries and 151 hospital term deliveries. RESULTS: Women who delivered out of hospital tended to be older (32 +/- 5.5 vs. 28 +/- 5.0 years, p = 0.046) and less educated (4.4 +/- 5.1 vs. 6.5 +/- 5.0 years, p = 0.005) as compared to women who delivered in the hospital. Unplanned out-of-hospital deliveries resulted in statistically significant higher rate of low-birth-weight newborns (< 2,500 g) (OR= 3.9, 95% CI 2.0-7.7, p<0.001), postpartum hemorrhage (OR = 8.4, 95% CI 1.1-181.1, p = 0.018) and trended for higher rate of manual lysis of retained placenta and membranes (4.0% vs. 0%, p = 0.013). Higher rates of admission to the neonatal intensive care unit due to neonatal complications, such as polycythemia (12.6% vs. 0%, p < 0.001), hypoglycemia (9.3% vs. 0.6%, p = 0.001) and convulsions (3.3% vs. 0%, p = 0.024), were noted in the out-of-hospital delivery group as compared to the controls. Using a multivariable analysis, lower educational level (OR = 0.4, 95% CI 0.3-0.4, p < 0.001), maternal age > 35 (OR = 6.2, 95% CI 2.3-16.7, p < 0.001) and high parity (OR = 7.9, 95% CI 4.9-12.9, p<0.001) were found to be independent risk factors for an unplanned outof hospital delivery. CONCLUSION: Unplanned out-of-hospital birth is an important risk factor for such complications as postpartum hemorrhage, low birth weight and adverse neonatal outcome.