Evaluating the impact of a trial of labor after cesarean section on labor duration: a retrospective cohort study.

BACKGROUND: Cesarean section (C-section) rates are increasing globally, and repeated C-sections are associated with increased maternal morbidity. Trial of labor after C-section (TOLAC) is an approach to reduce the recurrence of C-sections. However, limited research exists on the impact of cesarean scars on labor duration in TOLAC, considering the termination of labor through C-section and selection bias. This study aimed to investigate the impact of cesarean scars on labor duration in TOLAC participants, accounting for potential confounding factors and biases. METHODS: This retrospective cohort study included 2,964 women who attempted vaginal birth at a single center in Japan from 2012 to 2021. The study categorized participants into TOLAC (n = 187) and non-TOLAC (n = 2,777) groups. Propensity scores were calculated based on 14 factors that could influence labor duration, and inverse probability of treatment weighting (IPTW) was applied. Cox proportional hazards regression analysis estimated hazard ratios (HRs) for labor duration, with and without IPTW adjustment. Sensitivity analyses used propensity score matching, bootstrapping, and interval censoring to address potential biases, including recall bias in the reported onset of labor. RESULTS: The unadjusted HR for labor duration in the TOLAC group compared to the non-TOLAC group was 0.83 (95% CI: 0.70-0.98, P = 0.027), indicating a longer labor duration in the TOLAC group. After adjusting for confounding factors using IPTW, the HR was 0.98 (95% CI: 0.74-1.30, P = 0.91), suggesting no significant difference in labor duration between the groups. Sensitivity analyses using propensity score matching, bootstrapping, and interval censoring yielded consistent results. These findings suggested that the apparent association between TOLAC and longer labor duration was because of confounding factors rather than TOLAC itself. CONCLUSIONS: After adjusting for confounding factors and addressing potential biases, cesarean scars had a limited impact on labor duration in TOLAC participants. Maternal and fetal characteristics may have a more substantial influence on labor duration.

Barbed vs conventional sutures for cesarean uterine scar defects: a randomized clinical trial.

BACKGROUND: The role of barbed sutures in preventing myometrial defects and enhancing postpartum outcomes after cesarean section (C-section) is uncertain. OBJECTIVE: This study compared clinical and ultrasonographic outcomes of uterine scar defects after C-section with barbed and conventional smooth thread sutures. STUDY DESIGN: This was a multicenter, parallel-group, randomized, controlled clinical trial. Four obstetrics and gynecology departments across three Japanese healthcare regions were included. The participants were women requiring their first cesarean delivery between May 2020 and March 2023. Of the 1211 participants enrolled, 298 underwent C-section and 253 were followed up until July 2023. Participants with singleton pregnancies were randomly assigned (1:1 ratio) to receive either conventional or spiral thread sutures with a double-layer continuous suture. The study period comprised the time of consent to the 6- to 7-month examination. The primary endpoint was the rate of scar niches >2 mm evaluated using transvaginal ultrasonography at 6 to 7 months after surgery. Additional metrics included the total operative time, suture application time, operative blood loss, number of additional sutures required for hemostasis, maternal surgical complications, postoperative infections, surgeon's years of experience, and individual subscale scores. RESULTS: All data of the 220 participants (barbed suture group: 110; conventional suture group: 110) were available, thus enabling a full analysis set. A comparison of the barbed and conventional suture groups, respectively, revealed the following: niche length, 2.45±1.65 mm (range: 1.0-6.7) vs 3.79±1.84 mm (range: 1.0-11.0) (P<.001); niche depth, 1.78±1.07 mm (range: 1.0-5.7) vs 2.70±1.34 mm (range: 1.0-7.3) (P<.001); residual myometrial thickness (RMT), 8.46±1.74 mm (range: 4.8-13.0) vs 7.07±2.186 mm (range: 2.2-16.2) (P<.001); and niche width, 1.58±2.73 mm (range: 0.0-14.0) vs 2.88±2.36 mm (range: 0.0-11.0) (P<.001), respectively. The barbed suture group exhibited no defects and an RMT <3 mm. Furthermore, the barbed suture group had a lower rate of uterine niches (29.1%; n=32/110) than the conventional suture group (68.2%; n=75/110). Secondary outcomes showed no significant differences in operative times, maternal surgical complications, or postoperative complications. CONCLUSION: Double-layer barbed sutures during cesarean delivery may prevent C-section scar defects and postoperative complications. El resumen está disponible en Español al final del artículo.

Association of Regular Cervical Cancer Screening with Socioeconomic, COVID-19 Infection and Vaccine Status Among Japanese Population: Cohort Observational Study.

Purpose: Among the Organisation for Economic Co-operation and Development countries, Japan has one of the lowest cervical cancer screening coverages. Cancer screening coverage has worsened due to the coronavirus disease of 2019 (COVID-19) pandemic. This study investigated the relationship between socioeconomic background, COVID-19 infection history and vaccine status, and regular cervical cancer screening (CCS) during the two years of the COVID-19 era in Japan. Patients and Methods: We used data from the Japan COVID-19 and Society Internet Survey, a nationwide, Internet-based, self-report cohort observational study conducted in 2022. The outcome variable was identified by asking whether the participants had undergone CCS within the last two years. Cervical cytology was performed in Japan by brushing the external cervical os. This study used multivariate log-binomial regression models to evaluate inequalities during regular checkups for CCS. Adjusted prevalence ratios (APRs) with 95% confidence intervals (CIs) were estimated to incorporate the socioeconomic background variables. Results: Of the 12,066 participants, 5597 (46.4%) had undergone regular CCS for over two years. The prevalence ratio (PR) of patients who underwent CCS was 0.70 for those in their 20s and 0.78 for those in their 60s, compared to those in their 40s. Socioeconomic inequities were found in the following groups: unemployed/student, unmarried, high school graduate or lower, and household income below 4 million Yen. Our final multivariate analysis revealed that participants who were in their 20s or 60s, had a household income below 4 million Yen, were unmarried, had no annual health check-ups, and were unvaccinated with COVID-19 were at a higher risk of not undergoing CCS. Conclusion: The relationship between socioeconomic inequality and CCS hesitancy is prevalent among younger participants. The CCS coverage in Japan during the COVID-19 pandemic year (2020-2022) was not low compared with the pre-pandemic era.

Partner relationships, hopelessness, and health status strongly predict maternal well-being: an approach using light gradient boosting machine.

No recent study has explicitly focused on predicting the well-being of pregnant women. This study used data from an extensive online survey in Japan to examine the predictors of the subjective well-being of pregnant women. We developed and validated a light Gradient Boosting Machine (lightGBM) model using data from 400 pregnant women in 2020 to identify three factors that predict subjective well-being. The results confirmed that the model could predict subjective well-being in pregnant women with 84% accuracy. New variables that contributed significantly to this prediction were "partner help", "hopelessness," and "health status". A new lightGBM model was built with these three factors, trained and validated using data from 400 pregnant women in 2020, and predicted using data from 1791 pregnant women in 2021, with an accuracy of 88%. These factors were also significant risk factors for subjective well-being in the regression analysis adjusted for maternal age, region, parity, education level, and the presence of mental illness. Mediation analysis, with "hopelessness" as the mediator, showed that both "partner help" and "health status" directly and indirectly affected the outcome.

Endothelin-1 production via placental (pro)renin receptor in a mouse model of preeclampsia.

INTRODUCTION: Preeclampsia (PE) pathogenesis is explained by the two-stage disorder theory. However, mechanisms underlying hypertension and proteinuria in PE remain unclear. The role of (pro)renin receptor (PRR) in PE pathology has received special attention. We examined endothelin-1 (ET-1) production via placental PRR in a PE mouse model. METHODS: At 14.5 day-post-coitum (DPC), we performed a reduced uterine perfusion pressure (RUPP) operation, ligating the uterine arteriovenous vessels in female mice. We also infused these mice with a PRR inhibitor, decoy peptide in the handle region of prorenin (HRP) for mice (NH2-RIPLKKMPSV-COOH). At 18.5 DPC, blood, urine, and placenta were collected; fetus and placenta were weighed. We evaluated placental hypoxia using quantitative polymerase chain reaction (PCR), with hypoxia-inducible factor-1α (HIF-1α) as index. We also evaluated PRR, transforming growth factor-ß1 (TGF-ß1), and ET-1 expression in the placenta using quantitative PCR and western blotting. ET-1 concentration in blood plasma was assessed using enzyme-linked immunosorbent assay. RESULTS: Blood pressure and proteinuria significantly increased, and fetal and placental weights decreased in RUPP mice. HIF-1α, PRR, TGF-ß1, and ET-1 expressions considerably increased in RUPP mice placentas. ET-1 concentration in RUPP mice blood plasma was markedly increased. PRR inhibitor suppressed these changes. DISCUSSION: In PE model mice that underwent RUPP treatment, placental hypoxia increased PRR and ET-1 expression suggesting a causative relationship between ET-1 and intracellular PRR signaling. RUPP treatment, when combined with HRP, reversed the effect of elevated ET-1 levels in the model. This study may help to elucidate the pathogenesis of PE considering PRR and ET-1.

Protocol for a randomised, placebo-controlled, double-blinded clinical trial on the effect of oestrogen replacement on physical performance to muscle resistance exercise for older women with osteoarthritis of knee joint: the EPOK trial.

BACKGROUND: Knee osteoarthritis (KOA) is highly prevalent in older women, and previous studies suggest the involvement of hormonal factors play a role in the pathogenesis of osteoarthritis. KOA causes musculoskeletal impairment, resulting in decreased physical activity, muscle mass, and strength, which leads to sarcopenia and further increases the burden on healthcare systems. Oestrogen replacement therapy (ERT) improves joint pain and muscle performance in early menopausal women. Muscle resistance exercise (MRE) is a non-pharmacological method that preserves the physical functions of patients with KOA. However, data on short-term oestrogen administration combined with MRE in postmenopausal women, especially in those aged > 65 years, are limited. Therefore, this study presents a protocol of a trial aimed to examine the synergistic effect of ERT and MRE on lower-limb physical performance in older women with KOA. METHODS: We will conduct a double-blinded, randomised placebo-controlled trial in 80 Japanese women aged > 65 years living independently with knee pain. The participants will be randomly categorised into two groups: (1) 12-week MRE programme with transdermal oestrogen gel containing 0.54 mg oestradiol per push and (2) 12-week MRE programme with placebo gel. The primary outcome measured using the 30-s chair stand test, and secondary outcomes (body composition, lower-limb muscle strength, physical performance, self-reported measure of knee pain, and quality of life) will be measured at baseline, 3 months, and 12 months, and these outcomes will be analysed based on the intention-to-treat. DISCUSSION: The EPOK trial is the first study to focus on the efficacy of ERT on MRE among women aged > 65 years with KOA. This trial will provide an effective MRE to prevent KOA-induced lower-limb muscle weakness, confirming the benefit of short-term oestrogen administration. TRIAL REGISTRATION: Japan Registry of Clinical Trials: jRCTs061210062. Registered 17th December 2021, https://jrct.niph.go.jp/en-latest-detail/jRCTs061210062 .