Intrapartum rupture of the unscarred uterus

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.

Anticipating and responding to obstetric emergencies

During the last 10 years, international attention has focused on the importance of medical errors and patient safety. When obstetric emergencies occur, effective and efficient care is essential for good outcome and safety. This chapter presents a framework for obstetric safety, reviews the impact of obstetric emergencies on global health, and discusses possible interventions to improve the anticipation of and responses to obstetric emergencies.

Analysis of uterine rupture in a tertiary center in Eastern Nepal: Lessons for obstetric care

AIM

To determine the etiologic factors, clinical presentation, management and fetomaternal outcome in cases of rupture of the gravid uterus and propose preventive measures.

METHODS

A retrospective analysis of cases of uterine rupture was carried out at B.P. Koirala Institute of Health Sciences, Nepal, between February 1999 and January 2004.

RESULTS

There were 126 cases of uterine rupture with incidence of one in 112 deliveries. Twenty-five patients (19.8%) had a cesarean scar. Obstructed labor was the common antecedent factor in the unscarred group (46.5%) and use of oxytocics accounted for maximum ruptures (44%) in the scarred category. Patients with an unscarred uterus presented with hypotension and intrauterine death (89.1%), while abdominal tenderness (76%) and fetal distress (64%) were common modes of presentation in the scarred category. Complete rupture was seen in 84.9% of patients. Lateral wall ruptures (71.3%) necessitating hysterectomy (75.2%) were seen in the unscarred group. Anterior ruptures (92%) and repair (84%) were common in the scarred category. Maternal mortality was 13.5% and perinatal mortality 83.3%; these were both higher in the unscarred uterus.

CONCLUSION

The incidence of uterine rupture is high in Eastern Nepal and rupture of the unscarred uterus carries graver risks. Regular antenatal care, hospital deliveries and vigilance during labor with quick referral to a well-equipped center will reduce the incidence of this condition.

Unexplained Prelabor Uterine Rupture in a Term Primigravida

BACKGROUND

Uterine rupture is a catastrophic obstetric complication. The main risk factor is a scarred uterus, usually secondary to a previous cesarean delivery. Uterine rupture in a primigravid woman is a very rare event.

CASE

A 33-year-old primigravida presented at term with severe abdominal pain, signs of hemodynamic instability, and fetal bradycardia. She was not in labor, and the fetal heart tones disappeared before a cesarean could be performed. After a failed attempt at induction, exploratory laparotomy was performed for worsening maternal hemodynamic status. A complete rupture of the posterior uterine wall was found with a well-grown fetus free in the abdominal cavity. The uterus was repaired in two layers, and the patient did well postoperatively.

CONCLUSION

We report the rare occurrence of a spontaneous uterine rupture in a nonlaboring primigravid with no known risk factors. The differential diagnosis of this presentation includes concealed placental abruption, subhepatic hematoma with or without liver rupture, splenic rupture, rupture of the broad ligament, and rupture of a uterine vein. Although uterine rupture occurs more commonly in the multiparous population, it cannot be assumed that the primigravid uterus is immune to rupture.

Oxytocin-Associated Rupture of an Unscarred Uterus in a Primigravida

BACKGROUND

Intrapartum rupture of the unscarred uterus is an uncommon event, usually associated with such risk factors as grand multiparity, malpresentation, history of gestational trophoblastic disease, or instrumented delivery. Rupture during first pregnancy is extremely rare.

CASE

A 30-year-old primigravid woman was admitted for labor augmentation with oxytocin at 40.5 weeks of gestation. The oxytocin infusion rate was increased during the first and second stages of labor despite contractions occurring at a rate of 4-5 per 10 minutes. The uterus ruptured during second stage. Despite emergency cesarean delivery, the baby had evidence of severe asphyxia.

CONCLUSION

This case of uterine rupture in a primigravida with no prior uterine surgery and a structurally normal uterus underscores the importance of careful contraction monitoring and judicious control of oxytocin infusion rates.

Intrapartum fetal emergencies

Labour is one of the shortest yet most hazardous journeys humans take during their lifetime. Currently, our methods of identifying those fetuses at particular risk of compromise during labour are limited. Antepartum tests of placental reserve give little information about an individual fetus's ability to cope with passage through the birth canal and some might already have received a silent insult earlier in the pregnancy that places them at increased risk. In addition to the normal processes of labour, other, more unpredictable factors can act to place the fetus in acute danger.

Spontaneous uterine rupture in the first trimester: a case report

Uterine rupture is one of the most feared obstetric complications affecting the pregnant woman and fetus. Most of the cases have various risk factors and mainly occur during the second or third trimester. However, spontaneous uterine rupture during the first trimester is extremely rare. We experienced a case of spontaneous uterine rupture in a 36-yr-old multiparous woman without definite risk factors. The initial impression was a hemoperitoneum of an unknown origin with normal early pregnancy. Intensive surgical method would be needed for accurate diagnosis and immediate management in bad situation by hemoperitoneum even though a patient was early pregnancy.

“Silent” rupture of unscarred gravid uterus with subsequent pelvic abscess: Successful laparoscopic management

Intrapartum rupture of an unscarred uterus is rare in current times. However, it is still associated with significant maternal and fetal mortality and morbidity. Unlike rupture or dehiscence of a previous cesarean scar, which is occasionally bloodless, complete rupture of a gravid unscarred uterus frequently results in fetal jeopardy and significant maternal intraperitoneal bleeding, causes acute abdomen, and demands emergency surgical (laparotomy) intervention. Laparoscopy generally has no role in such circumstances due to the generally unstable maternal hemodynamic condition and the necessity of prompt fetal delivery with an abdominal approach. We present a rare case of intrapartum rupture of an unscarred gravid uterus with an atypical insidious clinical course. The diagnosis of complete uterine rupture was made 20 days after the patient's successful vaginal delivery, at which time a large pelvic abscess formed. The condition was successfully managed laparoscopically. Successful vaginal delivery, even with normal lochia, good uterine contraction, and stable vital signs, does not preclude the possibility of uterine rupture. For patients with unusual postpartum pelvic pain, uterine rupture should be considered as one of the possible etiologic factors, and prompt survey should be performed. Laparoscopic intervention may be valuable in such situations.

Oral misoprostol and uterine rupture in the first trimester of pregnancy: A case report

We are reporting the case of a woman with 8 weeks of amenorrhea who orally received a single dose of misoprostol 400 microg at midnight for ripening of cervix before uterine evacuation of an intrauterine gestational sac containing a single fetus (6.3 weeks of gestation) without cardiac activity. The patient had severe abdominal pain an hour later. Her blood pressure was 70/40 mmHg and her abdomen was slightly distended with direct and rebound tenderness. A transvaginal ultrasonography showed a 3-cm depth of a free fluid collection in the rectouterine pouch. Her hemoglobin and hematocrit levels were of 6.5 g/dL and 18.4%, respectively. A rupture of 1.5 cm at the left uterine horn with a protruding gestational sac was identified by laparoscopy. The gestational sac was removed and hemoperitoneal collection were successfully drained. The site of uterine rupture was primarily sutured and postoperative course was satisfactory. In summary, misoprostol administered in the first trimester of pregnancy may produce uterine rupture.

WHO systematic review of maternal mortality and morbidity: the prevalence of uterine rupture

OBJECTIVE

To determine the prevalence of uterine rupture worldwide.

DESIGN

Systematic review of all available data since 1990.

SETTING

Community-based and facility-based reports from urban and rural studies worldwide. Sample Eighty-three reports of uterine rupture rates are included in the systematic review. Most are facility based using cross-sectional study designs.

METHODS

Following a pre-defined protocol an extensive search was conducted of 10 electronic databases as well as other sources. Articles were evaluated according to specified inclusion criteria. Uterine rupture data were collected along with information on the quality of reporting including definitions and identification of cases. Data were entered into a database and tabulated using SAS software.

MAIN OUTCOME MEASURES

Prevalence of uterine rupture by country, period, study design, setting, participants, facility type and data source.

RESULTS

Prevalence figures for uterine rupture were available for 86 groups of women. For unselected pregnant women, the prevalence of uterine rupture reported was considerably lower for community-based (median 0.053, range 0.016-0.30%) than for facility-based studies (0.31, 0.012-2.9%). The prevalence tended to be lower for countries defined by the United Nations as developed than the less or least developed countries. For women with previous caesarean section, the prevalence of uterine rupture reported was in the region of 1%. Only one report gave a prevalence for women without previous caesarean section, from a developed country, and this was extremely low (0.006%).

CONCLUSION

In less and least developed countries, uterine rupture is more prevalent than in developed countries. In developed countries most uterine ruptures follow caesarean section. Future research on the prevalence of uterine rupture should differentiate between uterine rupture with and without previous caesarean section.

Late complications of operative hysteroscopy: predicting patients at risk of uterine rupture during subsequent pregnancy

The main purpose of this study was to identify predictors of uterine rupture following operative hysteroscopy. We also attempted to assess possible clinical or imaging methods in order to detect and avoid impending ruptures. A MEDLINE and EMBASE search of the English, German and French literatures was performed to retrieve case reports of uterine rupture following operative hysteroscopy. A total of 14 cases were retrieved. Twelve patients had a history of hysteroscopic metroplasty. Uterine perforation complicated operative hysteroscopy in eight cases and electrosurgery was used in nine cases. The interval between hysteroscopy and subsequent pregnancies varied from 1 month to 5 years with an average range of 16 months. Hysterosalpingogram follow-up was carried out in six cases and was considered normal in five cases. During pregnancy, serial ultrasound scans were performed in two cases to detect impeding rupture without success. Hysteroscopic metroplasty subjected patients to high risks of uterine rupture during subsequent pregnancies. Uterine perforation and/or the use of electrosurgery increase this risk but are not considered an independent risk factor. Uncomplicated hysteroscopic resection of submucous myomas and endometrial polyps did not alter obstetrical outcome. Apart from favourable use of scissors for hysteroscopic metroplasty, no accurate methods to prevent or detect impending ruptures in subsequent pregnancies were found. Physicians providing care for patients with previous hysteroscopic metroplasty or complicated operative hysteroscopy, should be aware of the potential risks for uterine rupture during pregnancy.

Obstetrical complications in gestational carrier pregnancies

OBJECTIVE

To report two cases of severe obstetrical complications in gestational carrier pregnancies and to review our clinical experience and compare our results with those reported in the literature.

DESIGN

Retrospective analysis.

SETTING

A university IVF program.

PATIENT(S)

Women without a functioning uterus or those whose pregnancy would exacerbate a medical condition were enrolled in the gestational carrier pregnancy program.

INTERVENTION(S)

IVF cycles using oocytes from genetic mothers (or oocyte donors) were performed, with ET to gestational carriers.

MAIN OUTCOME MEASURE(S)

Clinical pregnancy rates, obstetrical complications, and neonatal outcomes.

RESULT(S)

Ten couples underwent a total of 13 cycles using gestational carriers. A clinical pregnancy rate of 69% (9/13) was achieved. An intrapartum hysterectomy and a late puerperal hysterectomy were required because of severe obstetrical complications. The late puerperal hysterectomy was performed for placenta accreta in a triplet gestation. This carrier sustained multiple cerebral infarcts and blindness. One triplet infant died secondary to a hypoplastic left ventricle and complications of prematurity. A second gestational carrier with a singleton gestation underwent a hysterectomy for a uterine rupture, and the infant has cerebral palsy.

CONCLUSION(S)

The past medical and obstetrical histories of potential gestational carriers must be closely scrutinized, and candidates must be thoroughly counseled about the potential risks involved in the procedure.

Rupture of the pregnant uterus: a 9-year review

OBJECTIVE

To investigate the frequency of ruptured uterus, possible etiologic factors and fetomaternal outcomes.

STUDY DESIGN

A retrospective chart view of all patients with ruptured uterus over a 9-year period from 1995 to 2003 was carried out. Relevant data relating to the clinical features, characteristics of labour, operative procedures, and fetomaternal outcomes were assessed.

RESULTS

During the study period there were 17 cases of ruptured uterus among a total of 117,095 deliveries, giving an incidence of 1 in 6,888 deliveries. Thirteen patients (76.5%) were multiparous and mean parity was 1.9. Uterine rupture occurred following vaginal delivery in ten patients. Caesarean delivery was performed in seven (41.2%) patients, of which five (29.4%) patients had a history of previous caesarean section. Abdominal hysterectomy was performed in 12 patients (70.6%), of which 9 (75.0%) were total and 3 (25.0%) were subtotal. The other five patients (29.4%) had suture repairs. In seven patients (41.2%), uterine rupture was associated with oxytocin use. There were one maternal and three perinatal (17.6%) deaths.

CONCLUSION

Sudden fetal heart abnormalities in labouring patients should be taken as a potential sign of danger. Early diagnosis and immediate preoperative resuscitation are of great importance in cases of ruptured uterus. The fetomaternal outcomes can be improved with the experience and skill of the surgical team.

Pregnancy-Related Maternal Deaths

Pregnancy is a normal biologic process, but because of a variety of physiologic factors, it increases a woman's risk for death. Maternal deaths in pregnancy may be due to conditions unique to pregnancy, conditions associated with pregnancy, or conditions unrelated to but exacerbated by pregnancy. Death may occur during any trimester, during labor/birth, or postpartum. In this report, we present 45 cases of pregnancy-related maternal deaths that were investigated and autopsied at the Dallas County Medical Examiners office between 1977 and 1999, and we review the topic of pregnancy-related maternal death.

Uterine rupture: differences between a scarred and an unscarred uterus

OBJECTIVES

This study aimed to compare risk factors, site of rupture, and outcome of uterine rupture among patients with a scarred versus an unscarred uterus. Study design We conducted a comparison between all cases of uterine rupture (n=53) in women with a scarred versus an unscarred uterus, occurring between January 1988 and July 2002.

RESULTS

During the study period, there were ruptures among 26 patients with a scarred uterus and 27 patients without a uterine scar. No significant differences were noted between the scarred and unscarred groups while comparing risk factors such as birth order, birth weight, hydramnios, oxytocin induction, diabetes, and malpresentation. The main site of involvement in both groups was the lower uterine segment representing 92.6% of the ruptures in the unscarred group and 92.3% of the ruptures in the scarred uterus group. Cervical involvement was significantly more common among patients without a previous uterine scar (33.3% vs 7.7%; odds ratio [OR]=6.0, 95% CI, 1.16-31.23, P=.04). Conversely, uterus corpus involvement did not differ between the groups. Perinatal mortality did not differ between the groups. In addition, no significant differences were noted regarding maternal morbidity such as the need for hysterectomy, blood transfusion, or length of hospitalization.

CONCLUSION

Although cervical involvement was significantly more prevalent in the rupture of an unscarred uterus, no significant differences in maternal or perinatal morbidity were noted between rupture of a scarred versus an unscarred uterus.

Abdominal pain during pregnancy

Numerous medical, surgical, psychiatric, gynecologic, and obstetric disorders can cause abdominal pain during pregnancy. The patient history, physical examination, laboratory data, and radiologic findings usually provide the diagnosis. The pregnant woman has physiologic alterations that affect the clinical presentation, including atypical normative laboratory values. Abdominal ultrasound is generally the recommended radiologic imaging modality; roentgenograms are generally contraindicated during pregnancy because of radiation teratogenicity. Concerns about the fetus limit the pharmacotherapy. Maternal and fetal survival have recently increased in many life-threatening conditions, such as ectopic pregnancy, appendicitis, and eclampsia, because of improved diagnostic technology, better maternal and fetal monitoring, improved laparoscopic technology, and earlier therapy.

Spontaneous rupture of uterus

Spontaneous rupture of the uterus is a life-threatening obstetrical emergency. Diagnosis may be delayed because of the bizarre presentation or absence of significant pain and tenderness, which could have been masked by the analgesic medications used during labor. We present a case of spontaneous rupture in a multigravid female who was undergoing oxytocin-augmented labor while receiving epidural analgesia. She had had no previous cesarean deliveries or uterine surgery. Half an hour after an initial complaint of left inguinal pain, which was thought to be related to a patchy epidural block, she presented with changes in vital signs and significant fetal decelerations. At emergent cesarean section, a uterine rupture was noted. The uterine rupture extended down to the left vaginal angle, was not reparable and a hysterectomy was performed. The fetus survived.

Risk factors for arrest of descent during the second stage of labor

OBJECTIVE

To define obstetrical risk factors for arrest of descent during the second stage of labor and to determine perinatal outcome.

STUDY DESIGN

All singleton, vertex, term deliveries with an unscarred uterus, between the years 1988 and 1999 were included. Univariable and multivariable analysis were performed to investigate independent risk factors associated with arrest of descent during the second stage of labor and the perinatal outcome.

RESULTS

The study included 93266 deliveries, of these 1545 (1.7%) were complicated with arrest of descent during the second stage of labor. Using a multivariable analysis, the following obstetric risk factors were found to be significantly associated with arrest of descent: nulliparity (OR=7.8, 95% CI=6.9-8.7; P<0.001), birth weight >4 kg (OR=2.3, 95% CI=1.9-2.8; P<0.001), epidural analgesia (OR=1.8, 95% CI=1.6-2.0; P<0.001), hydramnios (OR=1.6, 95% CI=1.3-2.0; P<0.001), hypertensive disorders (OR=1.5, 95% CI=1.3-1.8; P<0.001), gestational diabetes A1 and A2 (OR=1.5, 95% CI=1.2-1.8; P<0.001), male gender (OR=1.4, 95% CI=1.2-1.5; P<0.001), premature rupture of membranes (PROM, OR=1.3, 95% CI=1.04-1.6; P=0.021), and induction of labor (OR=1.2, 95% CI=1.02-1.4; P=0.030). Deliveries complicated by arrest of descent resulted in cesarean section in 20.6%, vacuum extraction in 74.0%, and forceps delivery in 5.4%. Newborns delivered after arrest of descent during the second stage of labor had significantly higher rates of low Apgar scores (<7) at 1 and 5 min, as compared to the controls (12.7 vs. 2.1%, P<0.001; and 0.9 vs. 0.2%, P<0.001, respectively). Nevertheless, no significant differences were noted between the groups regarding perinatal mortality (0.38 vs. 0.44%; P=0.759).

CONCLUSIONS

Major risk factors for arrest of descent during the second stage of labor were nulliparity, fetal macrosomia, epidural analgesia, hydramnios, hypertensive disorders and gestational diabetes mellitus. These risk factors should be carefully evaluated during pregnancy in order to actively manage high-risk pregnancies.

Uterine rupture

Uterine rupture is an uncommon obstetric event. It is important because it continues to be associated with maternal mortality, especially in developing countries, and with major maternal morbidity, particularly peripartum hysterectomy. It is also associated with a high incidence of perinatal mortality and morbidity worldwide. This chapter examines the incidence, aetiology, clinical presentation, complications and prevention of uterine rupture. The key factor in the cause of rupture is whether or not the uterus is scarred. Rupture of an unscarred uterus is rare, usually traumatic, and its incidence decreases with improvement in obstetric practice. Rupture of the scarred uterus is more common, and usually occurs after a trial of labour in a patient with a previous Caesarean section. This chapter also explores how the incidence and complications of uterine rupture may be minimized, and yet the incidence of vaginal birth after Caesarean section (VBAC) optimized, in clinical practice.

Uterine rupture in second trimester abortion in a grand multiparous woman. A complication of misoprostol and oxytocin

Rupture of unscarred uterus during the second trimester is rare. There have been only 32 cases reported in the literature since 1968. A case of ruptured uterus in a grand multiparous woman is presented. To our knowledge, this might be the first reported case in the English literature of uterine rupture during second trimester termination of pregnancy using a prostaglandin E1 analogue (Misoprostol) and oxytocin.

Vaginal bleeding associated with pregnancy

Vaginal bleeding during pregnancy provokes physical and emotional stress to patients and physicians. Physicians must be prepared to assess the medical implications of acute blood loss to these patients and their unborn children quickly. When mother and fetus are stable, the recognition and treatment of the underlying cause is essential to decreasing additional maternal and fetal morbidity and mortality associated with the bleeding episode.

Obstetric uterine rupture: a four-year clinical analysis

OBJECTIVE

The purpose of our study was to identify the risk factors of uterine rupture during labour, to report maternal and neonatal outcome, and to propose preventive measures.

STUDY DESIGN

A retrospective study with review of patients' files and monitor strips was performed.

RESULTS

Between January 1, 1994 and November 30, 1998, there were 21 cases of uterine rupture at our institution. Of these, 6 patients had complete rupture, and 15 had incomplete rupture. The risk of uterine rupture was increased in patients who had a history of one or more Caesarean sections, obstructed labour, dysfunctional labour, and those who had injudicious use of uterine stimulants. There was no maternal death and fetal loss was 7 (33.3%).

CONCLUSIONS

The high incidence of uterine rupture is attributed to lack of prenatal care, labour in high-risk patients outside hospital because of declining economy, and more patients with two or more previously scarred uterus. The maternal and neonatal complications have remained very high in the developing countries. We recommend that all patients with a history of Caesarean delivery should be delivered in hospital and observed closely for progression of labour, recognition of an active phase arrest requires operative delivery.

Uterine emergencies. Atony, inversion, and rupture

Uterine atony, inversion, and rupture are potentially fatal events that may occur in pregnancy. They are obstetric emergencies that require immediate attention. Although all women may experience these complications, identification or known risk factors allow the obstetric team to prepare for rapid diagnosis and intervention. This article includes management options to help prepare for these uncommon events.

Pregnancy outcome after laparoscopic electromyolysis

Laparoscopic myolysis, a procedure designed to shrink uterine myomas by coagulating their blood supply, is an alternative to myomectomy or hysterectomy in women who do not contemplate childbearing. Three patients conceived within 3 months after myolysis against the surgeon's advice. In two of these women the uterus ruptured at 32 and 39 weeks' gestation, respectively, associated with death of the 32-week fetus. The third patient had an uneventful elective cesarean section at 39 weeks' gestation. Until the risk of uterine rupture after myolysis has been accurately compared with that after myomectomy, women should not undergo myolysis if they wish to conceive. Should pregnancy occur after myolysis, caution and intensive surveillance of mother and fetus must be applied, and cesarean section should be performed at earliest signs and symptoms of uterine rupture and at term before onset of labor.