There is a paucity of uterine oxytocin receptors during preterm gestation. Whether this affects the requirement of oxytocin dose for uterine contraction in patients with preterm gestation is not researched. We compared effective dose in 90% of target population (ED90) of oxytocin infusion for satisfactory uterine tone during cesarean delivery in patients with preterm and term pregnancy. This biased coin sequential allocation, dose finding study, with triple blinding to dose allocation included nonlaboring women >18 years posted for cesarean delivery under spinal block, into either term or preterm group (n = 30 each; completed or <37-week gestation, respectively). Oxytocin infusion was initiated at 13 IU·h-1 in the first patient in both groups. Dose in subsequent cases was determined by response to oxytocin in previous patient of a particular group (dosing interval = 2 IU·h-1). Uterine tone was assessed using the one-finger palpation method by the surgeon. Myometrial oxytocin receptor expression was also evaluated on tissue obtained during surgery, using immunohistochemistry (IHC). The ED90 of oxytocin infusion to prevent intraoperative uterine atony was 1.5 times greater in the preterm group (25.7 IU·h-1 [95% confidence interval {CI}, 16.4-35.1]) as compared to the term group (16.2 IU·h-1 [95% CI, 14.8-17.7]). Intraoperative oxytocin amount was significantly greater (14.3 [11.7-17.5] vs 12.8 [10.4-14.7] IU; P = .048), and the need of additional uterotonic was clinically higher (16% vs 10%; effect size = 0.5 [95% CI, 0.1-2.5]; P = .448) for the preterm group. IHC showed increased oxytocin receptor expression for term versus preterm group (P = .040). Incidence of oxytocin-associated hypotension was greater for preterm group (50% vs 13%; P = .002). During cesarean delivery, oxytocin requirement is almost 1.5 times greater for preterm as compared to term pregnancy. This was supported by decreased expression of the myometrial oxytocin receptor upon IHC.

Retrospective study of ten years of dystocic calving assisted by veterinarians in a bovine semi-extensive production grass-based system.

To determine whether an intrauterine balloon tamponade duration of 6 hours is noninferior to a duration of 18 hours for controlling bleeding after vaginal delivery, as measured by quantitative blood loss. In this pragmatic randomized trial of noninferiority, a 6-hour duration of intrauterine balloon tamponade usage for postpartum hemorrhage (PPH) control was compared with an 18-hour duration. We randomized participants with PPH due to uterine atony after vaginal delivery to an intrauterine balloon tamponade duration of 6 hours or 18 hours in a 1:1 ratio using stratified block randomization based on quantitative blood loss at the time of intrauterine balloon tamponade placement. The primary outcome was the total quantitative blood loss from the placement of the intrauterine balloon tamponade to 18 hours postplacement. Sixty-four participants were estimated to be required to determine whether total quantitative blood loss between groups was above our chosen noninferiority margin of 250 mL. Noninferiority t tests were considered noninferior at P<.05. Secondary outcomes included measures of escalation in PPH management. From October 2020 through May 2023, we randomized 64 participants with a mean quantitative blood loss at time of intrauterine balloon tamponade placement of 2,133 mL, with 31 individuals placed in the 18-hour duration group and 33 placed in the 6-hour duration group. All received their assigned intervention; however, two participants were excluded due to protocol violation. Characteristics were similar between groups. The median (IQR) quantitative blood loss 18 hours after intrauterine balloon tamponade placement was 135.0 mL in the 18-hour group (81-184 mL) and 110.0 mL in the 6-hour group (60-172 mL) (P<.001). Intrauterine balloon tamponade was successful in treating all randomized participants, with no difference in secondary outcomes between groups. Intrauterine balloon tamponade usage for 6 hours was noninferior to 18 hours of usage for mitigating blood loss after vaginal delivery PPH. It may be reasonable to remove an intrauterine balloon tamponade after 6 hours. ClinicalTrials.gov, NCT04467996.

Immune dysregulation in uterine atony could suggest new ways to treat postpartum hemorrhage

High risk and low incidence diseases: Postpartum hemorrhage.

Carbetocin versus oxytocin for the prevention of uterine atony during cesarean delivery: a real-world retrospective historical control cohort study (2022-2023).

Identifying and reporting dystocia in laboratory rodents.

Based on the hypothesis that the effect of general anesthesia (GA) vs. neuraxial anesthesia (NA) on postpartum hemorrhage (PPH) varies according to its underlying etiology, this study aimed to investigate the impact of the anesthetic technique on the risk of severe PPH indistinct clinical scenarios: (1) emergency cesarean deliveries at risk for uterine atony and (2) cases of placenta accreta spectrum (PAS) at risk for massive surgical hemorrhage. In this retrospective dual-cohort study, patients receiving GA in Cohort 1 were matched 1:3 to NA patients using propensity score matching (PSM). Cohort 2 comprised patients with PAS who underwent scheduled cesarean hysterectomy. The primary endpoint was severe PPH, and the results were analyzed statistically. In the matched Cohort 1 (n = 600), the incidence of severe PPH was significantly higher in the GA group compared to the NA group (21.3 vs. 9.8%). After adjusting for operative duration and tranexamic acid use, GA was independently associated with an almost threefold increased risk of severe PPH [Adjusted Odds Ratio (aOR): 2.91; 95% Confidence Interval (CI): 1.80-4.69; p < 0.001]. In contrast, in Cohort 2 (n = 75), the rate of severe PPH was high in both groups, with no significant difference observed (91.1 vs. 86.7%; p > 0.05). However, post-hoc Bayesian analysis indicated a > 99 and 91% probability that GA is associated with increased blood loss in Cohort 1 and Cohort 2, respectively. In our matched cohort, general anesthesia was associated with an almost threefold increase in the risk of severe PPH in emergency cesarean deliveries susceptible to uterine atony. In cases such as the placenta accreta spectrum, the primary determinant of hemorrhage is the underlying surgical pathology, and the role of anesthetic management appears to be secondary. However, these findings for the PAS cohort should be considered exploratory due to the small sample size. In general, these results strongly support the personalization of anesthetic strategies based on the expected etiology of hemorrhage to reduce maternal morbidity and mortality.

To determine the incidence of relaparotomy after cesarean delivery in a tertiary referral center, and to evaluate its indications, timing, and association with maternal morbidity. This retrospective study included women who underwent relaparotomy within 30 days following cesarean delivery between June 2020 and October 2025 in a tertiary center managing high-risk obstetric cases. Baseline maternal, obstetric, and operative characteristics were recorded. Relaparotomy indications were analyzed according to timing and primary cesarean indication. Maternal morbidity, hospital stay, and intensive care unit (ICU) admission were assessed. An exploratory Poisson regression analysis was performed to evaluate potential associations between baseline variables and repeated relaparotomy. Multivariable linear regression was used to analyze factors associated with perioperative hemoglobin change. Among 44 486 cesarean deliveries, 83 women required relaparotomy (0.19%). Uterine atony and hemorrhage were the most common indications for relaparotomy in the early postoperative period, whereas infectious complications became more frequent later. Bladder injury and intra-abdominal abscess were associated with longer hospitalization, while ICU stay did not differ significantly by indication. Repeated relaparotomy occurred in 15.7% of patients; no baseline maternal or operative variables were significantly associated with this outcome in exploratory analysis. Relaparotomies for non-atony bleeding were associated with greater hemoglobin decline, longer operative duration, and increased transfusion requirement. Maternal morbidity occurred in 20.5% of cases, and one maternal death was observed in a patient with placenta accreta spectrum complicated by hemorrhage. Relaparotomy after cesarean delivery, although rare, represents a severe postoperative event associated with substantial maternal morbidity. It is not limited to technically complex index procedures and may follow apparently uncomplicated surgeries. The predominance of hemorrhagic causes early and infectious causes later underscores the need for extended postoperative surveillance. Effective hemostatic control, early recognition of infection, and management in experienced tertiary centers are central to improving maternal outcomes.

Objective: The study aimed to assess the accuracy of two distinct methods for estimating blood loss (EBL) and to identify potential factors contributing to early-onset postpartum hemorrhage (PPH) following a vaginal delivery (VD). Methods: Women in singleton pregnancies undergoing spontaneous/induced VD were recruited for this prospective observational cohort study. Methods of EBL included: (1) visual assessment by an attending obstetrician (sEBL) and (2) implementation of a mathematical formula (fEBL). Early PPH was defined as a cumulative blood loss exceeding 500 mL within the first 24 h after delivery as reflected by clinical assessment. Results: During the study period, 485 women delivered vaginally, and early PPH was diagnosed in 29 cases (5.97%). Among patients with PPH, a significant increase in the duration of the 2nd (61 min. vs. 33.5 min., p < 0.05) and 3rd (13 min. vs. 7 min., p < 0.001) stages of labor, as well as in the application of a dinoprostone insert (31% vs. 10.5%, p < 0.01) was noted. Additionally, in the same cohort, uterine atony (41.4% vs. 1.5%, p < 0.001), 3rd/4th degree perineal rupture (6.9% vs. 0%, p < 0.01), fetal macrosomia (17.2% vs. 4.8%, p < 0.05) and stillbirth (6.9% vs. 0.2%, p < 0.05) occurred significantly more frequently. In both groups visual estimation of blood loss was significantly lower compared to fEBL: (PPH sEBL: 800 mL vs. fEBL 1439.6 mL, p < 0.001; control sEBL: 250 mL vs. fEBL 621.8 mL, p < 0.001). In the multivariate analysis, factors such as third stage of delivery time ≥ 30 min. (OR 11.6; 95% CI: 4.18-32.33), FBW ≥ 4000 g (OR 6.37; 95% CI: 1.54-26.3), and dinoprostone insert application (OR 4.33; 95%CI: 1.63-11.48) were selected as independent predictors of the PPH. Conclusions: Compared to mathematical formula, visual estimation of blood loss by an attending obstetrician is significantly decreased. Prolonged third stage of delivery, fetal macrosomia, and application of a dinoprostone insert are the strongest contributors to early PPH following a VD.

Paired-operator simulation training for intrauterine tamponade balloon placement: A feasibility study with integrated TeamSTEPPS assessment.

Understanding the mechanism of oxytocin-induced uterine contractility is critical for addressing conditions at both extremes of the uterine contractility spectrum, preterm labour and uterine atony. We hypothesized that oxytocin induces extracellular calcium influx and uterine contraction through activation of the transient receptor potential vanilloid 4 (TRPV4) channel. To test this hypothesis, uterine tissue was obtained with informed consent from pregnant patients undergoing term, non-labouring caesarean delivery. In human myometrial tissue and smooth muscle cells in primary culture (mSMCs), TRPV4 and oxytocin receptor (OXTR) proteins colocalize at distances less than 40nm. In mSMCs, both pharmacological blockade of TRPV4 and TRPV4 depletion via small interfering RNA prevent oxytocin-induced calcium influx and contraction. In contrast, voltage-gated calcium channel blockade does not diminish oxytocin-induced calcium transients. Pharmacological blockade of OXTR has no effect on TRPV4 agonist-induced calcium influx or contractility. In uterine tissue from patients with oxytocin-resistant uterine atony, there is a marked reduction in glycosylated OXTR expression and in proximity ligation between OXTR and TRPV4 compared with tissue from control patients with optimal postpartum contractility. Taken together, these findings demonstrate that in the gravid uterine smooth muscle, TRPV4 activation is required for oxytocin-induced uterine contraction. They also suggest reduced OXTR-TRPV4 protein-protein interaction as a novel pathophysiological mechanism underlying uterine atony in non-labouring parturients. These findings highlight the physiological importance of oxytocin signalling via the TRPV4 channel and may motivate the development of targeted, TRPV4-focused treatments to modulate uterine contractility. KEY POINTS: Oxytocin-induced contraction in smooth muscle cells from term pregnant human myometrium requires activation of the TRPV4 calcium channel. TRPV4 and oxytocin receptor (OXTR) colocalize at <40nM and interact functionally in myometrial smooth muscle cells. TRPV4 antagonism or siRNA-mediated TRPV4 knockdown abolishes oxytocin-induced calcium influx and contractility. In patients with oxytocin-resistant uterine atony, glycosylated OXTR quantity and TRPV4-OXTR colocalization are markedly reduced. These findings identify TRPV4 as a critical mediator of uterine contractility. TRPV4 antagonists may have a role as novel therapeutic agents for preventing or treating preterm labour.

26-CCC-10378-ACC FROM UTERINE ATONY TO CORONARY VASOSPASM: A CASE OF POSTPARTUM MYOCARDIAL INJURY

Vacuum-induced tamponade using urological catheters for postpartum hemorrhage.

Introduction: Peripartum/postpartum hysterectomy is a rare but life-saving intervention for uncontrolled obstetric hemorrhage.Placenta accreta spectrum (PAS) and uterine atony are the most common indications; yet their clinical context and operative pathways may differ, particularly in centers where PAS is managed under urgent or emergent conditions.We evaluated indications, surgical management, and outcomes over a 10-year period and explored differences between uterine atony-related and PAS-related cases. Material and Methods:This retrospective, single-center study included women who underwent peripartum or postpartum hysterectomy for uncontrolled obstetric hemorrhage between January 2015 and June 2025.Cases were classified as uterine atony or PAS/placenta previa-related hemorrhage based on operative findings, clinical course, and pathology.Continuous variables were summarized as median [interquartile range (IQR)] and compared using the Mann-Whitney U test; categorical variables were compared using Fisher's exact test.Effect estimates with 95% confidence intervals (bootstrap for continuous variables) are provided in the tables; comparisons were exploratory.Results: Among 31,571 deliveries, 34 hemorrhage-related peripartum/postpartum hysterectomies were identified (incidence: 1.1 per 1,000 deliveries): 18 for uterine atony (52.9%) and 16 for PAS-related

Does peripartum intravenous calcium administration reduce the occurrence of uterine atony in caesarean sections?: A systematic review and meta-analysis.

Monochorionic triamniotic multiple pregnancy is a rare and high-risk condition. We present the management of a cascade of severe complications in an adolescent pregnant patient. A 17-year-old primigravida with a 24-week monochorionic triamniotic triplet pregnancy was admitted for threatened preterm labor with cervical dilation. A rescuecervical cerclage was performed. The clinical course was complicated by high-risk pulmonary thromboembolism, confirmed by echocardiography and Doppler ultrasonography, requiring therapeutic anticoagulation. Subsequently, the patient developed nosocomial pneumonia and severe anemia. At 26.3 weeks of gestation, an emergency cesarean sectionwas performed due to labor, delivering three preterm newborns. The mother experienced uterine atony, which was successfully managed with compressive sutures. This case underscores the feasibility of an aggressive, multidisciplinary approach in critical obstetric situations with sequential complications. Individualized decision-making, despite limited evidence in such complex scenarios, can lead to favorable maternal and fetal outcomes. Adolescence may be an additional risk factor in multiple pregnancies.

Adenomyosis is the presence of endometrial glands and stroma within the myometrial wall of the uterus. This condition is related to a diffusely enlarged uterus with reactive hyperplasia and fibrosis of the surrounding myometrial smooth muscle cells. The symptomatology of adenomyosis is highly heterogeneous among patients and there are no pathognomonic symptoms specific to the condition. Clinically, although approximately 30% of patients remain asymptomatic, it can manifest as abnormal bleeding, pelvic pain, infertility and adverse obstetric outcome: miscarriage, preterm labor, uterine atony, other complications during labor. Diagnosis of adenomyosis relies on imaging techniques such as transvaginal ultrasound (TVUS) and magnetic resonance imaging (MRI). Precise ultrasound diagnosis enables the identification of symptomatic patients and allows for the implementation of appropriate treatments based on the severity of adenomyosis-related symptoms. Treatment options include pharmacological treatments usually with progestin or levonorgestrel-releasing intrauterine systems, hysteroscopic resection or ablation, conservative surgical methods and high-intensity focused ultrasound (HIFU). Diagnosis of adenomyosis during pregnancy can present challenges, as its symptoms may overlap with those of pregnancy, and it may be difficult to diagnose or differentiate from other conditions that affect the uterus during pregnancy. Additionally, imaging techniques commonly used to diagnose adenomyosis, such as transvaginal ultrasound and MRI, must be used cautiously due to the changes that occur in the uterus during pregnancy. Pregnancy leads to significant changes in the size and shape of the uterus, which can make the typical features of adenomyosis less apparent on imaging studies. Several studies suggest that adenomyosis may be linked to "unexplained infertility" and it is also conceived as a reproductive disorder, with reported prevalence rates of 38.2% in cases of recurrent pregnancy loss. Given the emerging evidence about the negative impact of adenomyosis on fertility and obstetric outcomes, accurate pre-conception and post-conception counseling is crucial. Treatment during pregnancy is generally conservative and they are based on symptoms control causing significant discomfort or interfere with pregnancy, management may include pain relief, such as acetaminophen or, in some cases, opioids (with caution) and careful monitoring throughout pregnancy. If adenomyosis is suspected during pregnancy, the condition is usually addressed post-delivery, and the approach to treatment depends on the severity of symptoms and any pregnancy complications that may arise. The aim of this review is to provide preconception and post-conception counselling for patients with adenomyosis, focusing on its impact on fertility and obstetric outcomes. It also aims to offer information on the symptoms and ultrasound diagnosis during pregnancy to ensure careful monitoring.

BACKGROUND: Cesarean delivery rates continue to rise, as does the percentage of intrapartum cesarean section, highlighting the relevance of research on the subject. Risk factors for emergency cesarean delivery include a burdened medical or obstetric and gynecological history (hypertension, diabetes mellitus, etc.) as well as pregnancy complications (pregnancy-induced hypertension, pre-eclampsia, gestational diabetes, fetal malpresentation, etc.). Analyzing these factors can help to identify risk groups, improve labor management, and reduce maternal and neonatal morbidity. AIM: The work aimed to assess the impact of maternal history and course of labor on the mode of delivery and neonatal outcomes. METHODS: The study included 391 patients. Patients were divided into the main group (intrapartum cesarean section) and the control group (cesarean section before the onset of labor). The main group was divided into three subgroups. Subgroup 1 (latent phase) included 48 patients who had a cesarean section at a cervical dilatation of 1–4 cm; subgroup 2 (active phase) included 43 patients who had a cesarean section at a cervical dilatation of 5–9 cm; and subgroup 3 included 195 patients who had a cesarean section at full dilatation. The control group (n = 105) included patients who had a cesarean section before the onset of labor. Each patient's medical records on the course of pregnancy and labor and mode of delivery were analyzed. RESULTS: Overweight and obesity were most common in the control group; moreover, this group had the shortest gestational age at the time of cesarean section. Chronic hypertension was more common in the active phase subgroup than in the full dilatation subgroup (р 0.05). Oxytocin induction was less common in the full dilatation subgroup (p 0.05). In the latent phase subgroup, primary uterine inertia was the most common indication for cesarean section (p 0.05), whereas secondary inertia was more common in the active phase and full dilatation subgroups (р 0.05). The full dilatation subgroup had the highest intraoperative blood loss (~ 600 mL; p 0.05). The highest birth weight was reported in the full dilatation subgroup (3632 g; p 0.05), while the highest 1-minute Apgar scores were observed in the latent phase subgroup (8 points; p 0.05). CONCLUSION: The maternal history and course of labor have a direct impact on the mode of delivery and neonatal outcomes. The findings highlight the relevance of assessing maternal history and course of labor in real-world practice.

This study analyzed 22 criminal cases involving obstetricians and gynecologists to identify legal trends and propose measures to reduce the legal burden on medical professionals while maintaining stable healthcare services. The cases were retrieved from the Supreme Court of Korea Judicial Information Disclosure Portal using keywords such as “obstetrics,” “gynecology,” “expectant mother,” “fetus,” “neonate,” “delivery,” “uterus,” and “placenta.” The cases were classified into two categories: medical malpractice (16 cases, 72.7%) and abortion and bioethics (6 cases, 27.3%). Guilty verdicts were issued in 8 cases (36.4%), whereas 14 cases (63.6%) resulted in acquittal. The qualitative analysis showed that courts consistently protected physicians’ clinical discretion in unpredictable and unavoidable situations, such as amniotic fluid embolism and uterine atony, provided that standard medical protocols were followed. Procedural appropriateness, rather than the perfection of clinical outcomes, appeared to be the primary basis for judicial protection. Although the judiciary acknowledges the inherent limitations of medical practice and tends to protect physicians when established guidelines are followed, the high frequency of criminal prosecution remains a substantial burden on healthcare providers and may threaten the sustainability of obstetric care.