Does oxytocin augmentation increase perinatal risk in primigravid labor?

Early Labor Posterior Uterine Wall Rupture in a Primigravid Mother with Successful Repair and Live Birth: A Case Report

Background

Posterior uterine wall rupture is extremely uncommon in the absence of any of the commonly recognized risk factors. Even though uterine rupture is more likely in multiparous people, it cannot be believed that the uterus of a primigravid is impervious to rupture. The objective of this case report is to alert obstetricians about atypical posterior uterine wall rupture presentation in the absence of identifiable risk factors and to emphasize the worth of prompt action.

Case Presentation

A 22-year-old primigravid mother with a 12 cm vertical posterior uterine wall rupture of an unscarred uterus at St. Paul's Hospital in Ethiopia was reported to have survived an intrapartum uterine rupture during the latent early stage of labor while taking a low dose of oxytocin. The baby was saved from the abdominal cavity after an emergency laparotomy was performed. Complete hemostasis was achieved when the posterior uterine wall rupture was repaired in two layers. The patient and her baby were discharged on the fifth postoperative day smoothly.

Conclusion

Posterior uterine wall rupture in a primigravid mother with an unscarred uterus is extremely rare, but a high index of suspicion should be kept in mind as expedited intervention is the only way to save the mother and fetus.

Prevalence of uterine rupture among women with one prior low transverse cesarean and women with unscarred uterus undergoing labor induction with PGE2: A systematic review and meta-analysis

BACKGROUND

As uterine rupture may affect as many as 11/1000 women with 1 prior cesarean birth and 5/10.000 women with unscarred uterus undergoing labor induction, we intended to estimate the prevalence of such rare outcome when PGE2 is used for cervical ripening and labor induction.

METHODS

We searched MEDLINE, ClinicalTrials.gov and the Cochrane library up to September 1st 2020. Retrospective and prospective cohort studies, as well as randomized controlled trials (RCTs) on singleton viable pregnancies receiving PGE2 for cervical ripening and labor induction were reviewed. Prevalence of uterine rupture was meta-analyzed with Freeman-Tukey double arcsine transformation among women with 1 prior low transverse cesarean section and women with unscarred uterus.

RESULTS

We reviewed 956 full text articles to include 69 studies. The pooled prevalence rate of uterine rupture is estimated to range between 2 and 9 out of 1000 women with 1 prior low transverse cesarean (5/1000; 95%CI 2-9/1000, 122/9000). The prevalence of uterine rupture among women with unscarred uterus is extremely low, reaching at most 0.7/100.000 (<1/100.000.000; 95%CI <1/100.000.000-0.7/100.000, 8/17.684).

CONCLUSIONS

Uterine rupture is a rare event during cervical ripening and labor induction with PGE2.

Uterine rupture in a primigravid patient, an uncommon but severe obstetrical event: a case report

BACKGROUND

A spontaneous rupture of the unscarred uterus in a primigravid patient is extremely rare and is associated with high perinatal and maternal morbidity and mortality.

CASE PRESENTATION

A 34-year-old white primigravid woman, 31 + 3 weeks of gestation, presented with pre-eclampsia and developed a sudden acute abdomen. An emergency laparotomy was performed and a uterine rupture was found as the cause of the event. A stillborn girl was born.

CONCLUSION

A rupture of the pregnant uterus should always be considered in a pregnant woman presenting with abdominal pain, even in a primigravid patient.

Acute uterine rupture in spontaneous term labour in a healthy primigravida: case report and review of the literature

Uterine rupture is an obstetric complication with potential catastrophic fetal and maternal consequences, if not detected early and managed promptly. We report a case of a 32-year-old primigravida in spontaneous labour at term who had unprovoked acute uterine rupture. Operative findings at emergency caesarean section were a live female infant weighing 3150 g requiring resuscitation, massive haemoperitoneum, and large right vertical posterolateral uterine rupture at the upper segment, extending to the ovarian pedicle and down to the vagina vault.

Identification of a myometrial molecular profile for dystocic labor

Background

The most common indication for cesarean section (CS) in nulliparous women is dystocia secondary to ineffective myometrial contractility. The aim of this study was to identify a molecular profile in myometrium associated with dystocic labor.

Methods

Myometrial biopsies were obtained from the upper incisional margins of nulliparous women undergoing lower segment CS for dystocia (n = 4) and control women undergoing CS in the second stage who had demonstrated efficient uterine action during the first stage of labor (n = 4). All patients were in spontaneous (non-induced) labor and had received intrapartum oxytocin to accelerate labor. RNA was extracted from biopsies and hybridized to Affymetrix HuGene U133A Plus 2 microarrays. Internal validation was performed using quantitative SYBR Green Real-Time PCR.

Results

Seventy genes were differentially expressed between the two groups. 58 genes were down-regulated in the dystocia group. Gene ontology analysis revealed 12 of the 58 down-regulated genes were involved in the immune response. These included (ERAP2, (8.67 fold change (FC)) HLA-DQB1 (7.88 FC) CD28 (2.60 FC), LILRA3 (2.87 FC) and TGFBR3 (2.1 FC)) Hierarchical clustering demonstrated a difference in global gene expression patterns between the samples from dystocic and non-dystocic labours. RT-PCR validation was performed on 4 genes ERAP2, CD28, LILRA3 and TGFBR3

Conclusion

These findings suggest an underlying molecular basis for dystocia in nulliparous women in spontaneous labor. Differentially expressed genes suggest an important role for the immune response in dystocic labor and may provide important indicators for new diagnostic assays and potential intrapartum therapeutic targets.

Dystocia correlates with body mass index in both spontaneous and induced nulliparous labors

OBJECTIVE

To assess the influence of body mass index (BMI) on labor outcome in both induced and actively managed spontaneous nulliparous labors.

METHODS

This is a prospective observational study of all consecutive nulliparous women who delivered in the National Maternity Hospital, Dublin in 2008. Labor outcome variables examined in relation to BMI included duration of labor, oxytocin requirements, epidural use, mode of delivery, and infant birthweight.

RESULTS

Of 4162 nulliparous women who labored during the study period, accurate BMI data were available on 3158, who constituted the study group. Of these women, 2143 (68%) were in spontaneous labor and 1015 (32%) had labor induced. A statistically significant association was found between maternal BMI at first antenatal visit and the need for intrapartum cesarean section (CS) in both spontaneous and induced labors (p < 0.05). A significantly poorer response to oxytocin augmentation was observed in women with a higher BMI, as indicated by an increased intrapartum CS rate for dystocia despite oxytocin augmentation. There was a linear relationship between maternal BMI and gestational age at onset of spontaneous labor.

CONCLUSION

Our results in a large consecutive series of nulliparous labors confirm the potent influence of increasing maternal BMI on intrapartum events.

Labor augmentation with oxytocin decreases glutathione level

Objective. To compare oxidative stress following spontaneous vaginal delivery with that induced by Oxytocin augmented delivery. Methods. 98 women recruited prior to labor. 57 delivered spontaneously, while 41 received Oxytocin for augmentation of labor. Complicated deliveries and high-risk pregnancies were excluded. Informed consent was documented. Arterial cord blood gases, levels of Hematocrit, Hemoglobin, and Bilirubin were studied. Glutathione (GSH) concentration was measured by a spectroscopic method. Plasma and red blood cell (RBC) levels of Malondialdehyde indicated lipid peroxidation. RBC uptake of phenol red denoted cell penetrability. SPSS data analysis was used. Results. Cord blood GSH was significantly lower in the Oxytocin group (2.3 +/- 0.55 mM versus 2.55 +/- 0.55 mM, P = .01). No differences were found in plasma or RBC levels of MDA or in uptake of Phenol red between the groups. Conclusion. Lower GSH levels following Oxytocin augmentation indicate an oxidative stress, though selected measures of oxidative stress demonstrate no cell damage.

Rupture of the Primigravid Uterus: A Review of the Literature

Uterine rupture is a catastrophic obstetric complication, associated with high rates of perinatal morbidity and mortality. The most common risk factor is previous uterine surgery, and most cases of uterine rupture occur in women with a previous cesarean delivery. Traditionally, the primigravid uterus has been considered almost immune to spontaneous rupture. In fact, although spontaneous rupture of the primigravid uterus is indeed a very rare event, a number of such cases have been reported recently. Prompt recognition of uterine rupture and expeditious recourse to laparotomy are critical in influencing perinatal and maternal morbidity. Not all uterine ruptures present with the typical clinical picture of abdominal pain, hypovolemia, vaginal bleeding, and fetal compromise. Therefore, it is important to maintain a high index of suspicion for uterine rupture in women presenting with some, or all, of these features, regardless of parity. Here we provide a systematic review of cases of spontaneous uterine rupture in primigravid women reported in the literature to date. Clinical presentation, differential diagnosis, common etiological factors, complication rates, and appropriate management of this rare obstetric event are discussed.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to recall that uterine rupture in a primigravida is a rare event, without typical signs and symptoms, and explain that the morbidity and mortality of the mother and child is directly related to a high index of suspicion and prompt treatment by the clinician.

Active Management of Labor

A source of great controversy, the active management of labor as classically defined, is routinely misunderstood and misapplied in many clinical settings. Aggressive induction protocols, early amniotomy, operative delivery, epidural analgesia, and even early admission to labor and delivery units are actions frequently thought to be synonymous with "active management of labor". To regain an understanding of the active management of labor, one needs to examine the goal of this management scheme and become more familiar with its components.

The elective use of oxytocin infusion during labour in nulliparous women using epidural analgesia: a randomised double-blind placebo-controlled trial

The obstetric outcome following the elective use of oxytocin infusion was determined in a randomised, double-blind placebo-controlled trial. 93 nulliparous women in a London hospital, who had requested epidural analgesia in labour (</= 6 cm.), were given an infusion of oxytocin (n = 46) or placebo (n = 47). The initial epidural dose was 15 ml of 0.125% bupivacaine, followed by an infusion at 10 ml per h, with 15 ml top-ups if required. When oxytocin was used electively there was a reduction in the length of the first stage of labour from 696 min to 578 min, (P < 0.05) even though more than half of the control group (53%) required oxytocin augmentation. There was no significant difference between the number of operative deliveries (34 [74%] vs 35 [74%]). The rotational delivery rate was less in the study group (2 [4%] vs 5 [11%]), though this did not reach significance. There were no adverse effects on the fetus, as judged by cord pH measurement, Apgar score, admission to the special care baby unit and neonatal jaundice. The prophylactic use of oxytocin in nulliparous women with epidurals reduces the length of the first stage of labour and appears to be safe. It does not reduce the operative delivery rate.

The continuing effectiveness of active management of first labor, despite a doubling in overall nulliparous cesarean delivery

OBJECTIVE

The purpose of this study was to determine the continuing effectiveness of active management of labor, a protocol that involves early detection and correction of dystocia with oxytocin in spontaneous cephalic nulliparous labor, by analysis of the contribution of this cohort to a doubled overall nulliparous cesarean delivery rate.

STUDY DESIGN

This was a retrospective analysis of annually collated institutional data on cesarean delivery and perinatal outcome.

RESULTS

From 1989 to 2000, 81,855 women were delivered at the National Maternity Hospital, of whom 34,201 women (42%) were nulliparous; the annual proportion of nulliparous women in spontaneous labor decreased progressively from 83% to 60%; the overall nulliparous cesarean rate increased from 8.1% to 16.6%. Cesarean birth rate among nulliparous women in spontaneous labor, although showing a significant upward trend between 1989 and 2000 (2.4%-4.8%; P = .001), was stable, averaging 5% for the last 8 years (P = .705); the peripartum death rate in this group fell significantly (P = .024). Comparing results for 1989 with results for 2000, nulliparous women in spontaneous labor accounted for 14% of the overall increase in cesarean deliveries (dystocia, 5%), compared with 51% for nulliparous women with induced labor. The perinatal mortality rate in term infants was unchanged.

CONCLUSION

Active management of spontaneous first labors remains an effective protocol for the promotion of vaginal delivery with low peripartum mortality rates; factors other than dystocia in spontaneous labor account for the progressive increase in the nulliparous cesarean delivery rate.

Graphic analysis of actively managed labor: prospective computation of labor progress in 500 consecutive nulliparous women in spontaneous labor at term

OBJECTIVE

Active management has been shown to shorten the length of labor and reduce the incidence of prolonged labor. We examined the influence of this protocol on the rate of cervical dilatation by calculating a mean partogram to explain how this acceleration is achieved.

STUDY DESIGN

We retrospectively analyzed partograms of cervical dilation in 500 consecutive nulliparous women in spontaneous labor at term with a singleton fetus in a cephalic presentation; cesarean deliveries were not excluded. Mean cervical dilations at admission and mean time intervals to reach 2, 3, 4, 6, 8, and 10 cm of dilatation and delivery were calculated, with 95% confidence intervals, both for the whole cohort and specifically in women with cervical dilatations <3 cm at admission. These data were used to construct mean partograms.

RESULTS

The mean duration of labor was 6.1 hours. The mean cervical dilatation at admission was 1. 7 cm; all but 2.8% were delivered within 12 hours. The cesarean rate was 5.4%. The mean partogram, with narrow 95% confidence intervals, shows a rapid active phase after a much shorter latent phase than reported in other analyses of labor.

CONCLUSION

Active management reduces the duration of first labor mainly by shortening the latent phase in association with amniotomy at very early cervical dilatations and does not delay the diagnosis of labor until the active phase has begun.

Uterine rupture during labour in a primigravida

Uterine rupture is extremely rare in the absence of any of the commonly recognized risk factors. We describe here a case of incomplete uterine rupture in a woman in her first pregnancy who had no previous instrumentation to the genital tract. Her only significant history was that of 2 episodes of minor antepartum haemorrhage occurring prior to induction of labour with artificial rupture of membranes and intravenous oxytocin. The rupture was manifested by 450 mL blood in the peritoneal cavity when an emergency Caesarean section was performed for persistent fetal bradycardia.

Nulliparous caesarean section in the home of active management of labour

The world-wide incidence of Caesarean section continues to rise with dystocia recognized as the major indication. Active management of labour has been proposed as an alternative treatment to Caesarean section for dystocia. At the National Maternity Hospital, Dublin, a recent increase in the Caesarean section rate has been observed. This retrospective review reveals this to be due to other indications.

Pharmacological Management of Labor

Normal spontaneous labor at term without maternal or fetal complications does not always occur. In these situations, pharmacological intervention is often the safest and most suitable method of delivery. The pharmacological management of labor includes the use of multiple agents that alter cervical dilatation and uterine contractions, resulting in delivery of the fetus and treatment of postpartum emergencies. This article provides a description of normal and abnormal labor patterns and possible peripartum complications. The use of oxytocin, ergot derivatives, and prostaglandins for augmentation of dysfunctional labor, induction of labor, and management of peripartum emergencies is discussed to provide information on availability of product, indications for use, clinical efficacy, potential adverse effects, and contraindications to use.