Risk factors and outcomes associated with type of uterine rupture

Risk factors for maternal complications following uterine rupture: a 12-year single-center experience

PURPOSE

To determine maternal outcomes and risk factors for composite maternal morbidity following uterine rupture during pregnancy.

METHODS

A retrospective cohort study including all women diagnosed with uterine rupture during pregnancy, between 2011 and 2023, at a single-center. Patients with partial uterine rupture or dehiscence were excluded. We compared women who had composite maternal morbidity following uterine rupture to those without. Composite maternal morbidity was defined as any of the following: maternal death; hysterectomy; severe postpartum hemorrhage; disseminated intravascular coagulation; injury to adjacent organs; admission to the intensive care unit; or the need for relaparotomy. The primary outcome was risk factors associated with composite maternal morbidity following uterine rupture. The secondary outcome was the incidence of maternal and neonatal complications following uterine rupture.

RESULTS

During the study period, 147,037 women delivered. Of them, 120 were diagnosed with uterine rupture. Among these, 44 (36.7%) had composite maternal morbidity. There were no cases of maternal death and two cases of neonatal death (1.7%); packed cell transfusion was the major contributor to maternal morbidity [occurring in 36 patients (30%)]. Patients with composite maternal morbidity, compared to those without, were characterized by: increased maternal age (34.7 vs. 32.8 years, p = 0.03); lower gestational age at delivery (35 + 5 vs. 38 + 1 weeks, p = 0.01); a higher rate of unscarred uteri (22.7% vs. 2.6%, p < 0.01); and rupture occurring outside the lower uterine segment (52.3% vs. 10.5%, p < 0.01).

CONCLUSION

Uterine rupture entails increased risk for several adverse maternal outcomes, though possibly more favorable than previously described. Numerous risk factors for composite maternal morbidity following rupture exist and should be carefully assessed in these patients.

Clinical analysis of incomplete rupture of the uterus secondary to previous cesarean section

Uterine rupture is a rupture of the body or lower part of the uterus during pregnancy or delivery. Total of 98 cases with incomplete uterine rupture were classified as the incomplete uterine rupture group, 100 cases with a history of cesarean delivery without uterine rupture were classified as the non-ruptured uterus group, and controls were selected using a systematic sampling method. The maternal age ≥35 years were associated with 2.18 times higher odds of having an incomplete uterine rupture. The odd of having an incomplete uterine rupture was 3.744 times higher for a woman with delivery interval ≤36 months. Having pregnancy complication was associated with 3.961 times higher odds of having an incomplete uterine rupture. The neonatal weight was lighter in the incomplete uterine rupture group (P = 0.007). The number of preterm birth and transfer to the NICU were higher in the incomplete uterine rupture group (P ＜ 0.01). The operation time and the length of time in hospital were longer in the group with incomplete uterine rupture (P ＜ 0.01). Age ≥35 years, delivery interval ≤36 month, and pregnancy with complication were independent risk factors of incomplete rupture of the uterus secondary to previous cesarean section.

Risk of uterine rupture in multiparous women after induction of labor with prostaglandin: A national population-based cohort study

OBJECTIVE

To assess whether, after induction of labor with prostaglandin, multiparous (≥2 para) women have an increased risk of uterine rupture compared with nulliparous or uniparous women.

METHODS

This was a retrospective population-based cohort study including women who underwent induction with prostaglandin in all maternity wards in Sweden between May 1996 and December 2019 (n = 56 784). The study cohort was obtained by using data from the Swedish Medical Birth Register, which contains information from maternity and delivery records. The main outcome measure was uterine rupture.

RESULTS

Overall, multiparous women induced with prostaglandin had an increased risk of uterine rupture compared with nulliparous women (adjusted odds ratio [OR], 3.33 [95% confidence interval (CI), 1.38-8.04]; P < 0.007). Multiparous women with no previous cesarean section (CS) induced with prostaglandin had more than three times higher risk of uterine rupture (crude OR, 3.55 [95% Cl, 1.48-8.53]; P = 0.005) compared with nulliparous women and four times higher risk compared with uniparous women (OR, 4.10 [95% CI, 1.12-15.00]; P < 0.033). Multiparous women with previous CS had a decreased risk of uterine rupture compared with uniparous women with one previous CS (crude OR, 0.41 [95% Cl, 0.21-0.78]; P = 0.007).

CONCLUSION

Our study implies that multiparity in women with no previous CS is a risk factor for uterine rupture when induced with prostaglandin. This should be taken into consideration when deciding on the appropriate method of induction.

Crucial factors for implementing treatment strategies in intractable atonic postpartum haemorrhage: early phase contrast medium extravasation on dynamic CT

AIM

To identify the relationship between contrast medium extravasation (CME) on dynamic contrast-enhanced computed tomography (DCT) and clinical information in intractable atonic postpartum haemorrhage (PPH) and its relevance to treatment with uterine artery embolisation (UAE).

MATERIALS AND METHODS

Of 90 patients who underwent DCT to diagnose PPH, 60 diagnosed with intractable atonic PPH were investigated retrospectively. Maternal background and clinical indicators were analysed to compare the positive and negative factors of early phase CME. Regression analysis was used to investigate the factors associated with CME. The sensitivity, specificity, and positive and negative predictive values of early phase CME for predicting UAE were calculated. Clinical outcomes were compared between the two groups according to the timing of the decision to undergo UAE.

RESULTS

Of the 60 patients with intractable atonic PPH, 21 underwent UAE, 20 of whom had early phase CME on DCT. Pre-DCT clinical parameters and clinical indices were not significantly different in presence of early phase CME. Early phase CME was associated with UAE performance, with a sensitivity of 95%, specificity of 87%, positive predictive value of 80%, and negative predictive value of 97%. In cases where UAE was performed after conservative management, there was a significant increase in blood loss and transfusion volume.

CONCLUSION

Early phase CME is not indicated by background factors or clinical findings. UAE is not required when CME cannot be detected in the uterine cavity. If early phase CME is present, UAE should be considered immediately.

Uterine scars after caesarean delivery: From histology to the molecular and ultrastructural level

Uterine rupture during a trial of labor after caesarean delivery (CD) is a serious complication for mother and fetus. The lack of knowledge on histological features and molecular pathways of uterine wound healing has hindered research in this area from evolving over time. We analysed collagen content and turnover in uterine scars on a histological, molecular and ultrastructural level. Therefore, tissue samples from the lower uterine segment were obtained during CD from 16 pregnant women with at least one previous CD, from 16 pregnant women without previous CD, and from 16 non-pregnant premenopausal women after hysterectomy for a benign disease. Histomorphometrical collagen quantification showed, that the collagen content of the scar area in uterine wall specimens after previous CD was significantly higher than in the unscarred myometrium of the same women and the control groups. Quantitative real-time PCR of uterine scar tissue from FFPE samples delineated by laser microdissection yielded a significantly higher COL3A1 expression and a significantly lower COL1A2/COL3A1 ratio in scarred uteri than in samples from unscarred uteri. Histological collagen content and the expression of COL1A2 and COL3A1 were positively correlated, while COL1A2/COL3A1 ratio was negatively correlated with the histological collagen content. Transmission electron microscopy revealed a destroyed myometrial ultrastructure in uterine scars with increased collagen density. We conclude that the high collagen content in uterine scars results from an ongoing overexpression of collagen I and III. This is a proof of concept to enable further analyses of specific factors that mediate uterine wound healing.

Unexpected Uterine Rupture-A Case Report, Review of the Literature and Clinical Suggestions

BACKGROUND AND OBJECTIVES

Women with a history of cesarean section are a high-risk group because they are likely to develop uterine rupture during their next pregnancy. Current evidence suggests that a vaginal birth after cesarean section (VBAC) is associated with lower maternal mortality and morbidity than elective repeat cesarean delivery (ERCD). Additionally, research suggests that uterine rupture can occur in 0.47% of cases of trial of labor after cesarean section (TOLAC).

CASE DESCRIPTION

A healthy 32-year-old woman at 41 weeks of gestation, in her fourth pregnancy, was admitted to the hospital due to a dubious CTG record. Following this, the patient gave birth vaginally, underwent a cesarean section, and successfully underwent a VBAC. Due to her advanced gestational age and favorable cervix, the patient qualified for a trial of vaginal labor (TOL). During labor induction, she displayed a pathological CTG pattern and presented symptoms such as abdominal pain and heavy vaginal bleeding. Suspecting a violent uterine rupture, an emergency cesarean section was performed. The presumed diagnosis was confirmed during the procedure-a full-thickness rupture of the pregnant uterus was found. The fetus was delivered without signs of life and successfully resuscitated after 3 min. The newborn girl of weight 3150 g had an Apgar score of 0/6/8/8 at 1, 3, 5, and 10 min. The uterine wall rupture was closed with two layers of sutures. The patient was discharged 4 days after the cesarean section without significant complications, with a healthy newborn girl.

CONCLUSIONS

Uterine rupture is a rare but severe obstetric emergency and can be associated with maternal and neonatal fatal outcomes. The risk of uterine rupture during a TOLAC attempt should always be considered, even if it is a subsequent TOLAC.

Intraoperative ultrasound during repeat cesarean delivery facilitates sampling of uterine scar tissue

OBJECTIVES

Histological examination of uterine scars provides insight into uterine wound healing and helps to develop prevention methods of uterine wall rupture after previous uterine surgery. Therefore, exact intraoperative scar identification is needed for specimen collection from the actual scar tissue. The aim of this study was to correlate pre- and intraoperative ultrasound measurements of the lower uterine segment (LUS) with histological findings of scar tissue and to evaluate the relevance of intraoperative ultrasound.

METHODS

In a prospective observational study, preoperative and intraoperative sonographic measurements of the LUS thickness were performed in 33 women with a history of at least one cesarean delivery. Intraoperative ultrasound with a linear transducer placed directly on the uterus identified the scar area and uterotomy was performed 2 cm cranially. Tissue samples were taken after extraction of the fetus, embedded in paraffin wax, and stained according to Gomori Trichrome to identify scar tissue. Collagen content was evaluated with imaging software Fiji (NIH, Bethesda, USA). Preoperative and intraoperative sonographic measurements were correlated with histologic evidence of scar tissue.

RESULTS

Histological evidence of scar tissue was found in 11 out of 33 samples with significantly lower ultrasonographic thickness of the lower uterine segment compared to the other 22 samples, both antepartum (1.4 mm [1.3-1.9] vs. 2.0 mm [1.6-2.6], p=0.03) and intrapartum (1.6 mm [1.3-1.9] vs. 3.7 mm [2.0-4.7], p<0.01). Intraoperative ultrasound had a significantly higher predictive power (AUC difference 0.18 [0.03-0.33], p=0.01).

CONCLUSIONS

Intraoperative sonography identifies the uterine wall area with histologically confirmable scar tissue far better than preoperative sonography.

Spontaneous Rupture of Unscarred Uterus in a Term Primagravida with Lethal Skeletal Dysplasia Fetus (Thanatophoric dysplasia). A Case Report and Review of the Literature

Background and Importance

 Spontaneous uterine rupture, especially in an unscarred uterus, is a rare pregnancy complication that can cause severe morbidity and mortality in both the mother and the fetus. The vast majority of uterine ruptures occur in the presence of a previous uterine scar, most commonly from a previous cesarean delivery. To our knowledge, here we reported the first case of spontaneous rupture of unscarred uterus in a term primigravida secondary to lethal skeletal dysplasia fetus (Type 1 Thanatophoric dysplasia) faced by a practicing clinician in an underdeveloped country (Somalia) with a successful outcome.

Case Presentation

 The patient was 24 yrs. Old Primagravida, at 40 weeks gestation by LMP, presented with abdominal pain and active vaginal bleeding; she did not receive antenatal care during pregnancy; after initial abdominal ultrasonography and vaginal examination, laparotomy was performed due to high suspicion of uterine rupture. After dead fresh fetal extraction, the uterine defect was repaired successfully, and the patient was discharged home in good condition after several days.

Conclusion

 Through this case, we would like to highlight the urgent need to focus on and recognize the importance of receiving antenatal care in the community so that the burden of thousands of lives lost each year can be reduced.