International Journal of Gynecology & Obstetrics最新文献

Pre-eclampsia (PE) and fetal growth restriction (FGR) are among the leading causes of maternal and perinatal morbidity and mortality worldwide. Both conditions are more frequent and severe at high altitudes due to physiological changes in oxygen availability and vascular adaptation. This narrative review explores the complex relationship between high-altitude pregnancy, the development of PE and FGR, and the underlying adaptive mechanisms that may influence maternal and fetal outcomes. We provide an updated synthesis of the current evidence regarding placental dysfunction, angiogenic imbalance, and oxidative stress in pregnancies at high altitude, highlighting the role of hypoxia-inducible factors, altered expression of sFlt-1 and PlGF, and their impact on trophoblast invasion and uteroplacental blood flow. The review also highlights genetic and physiological adaptations observed in permanent high-altitude populations that appear to mitigate these risks, including enhanced oxygen delivery, increased uterine artery diameter, and reduced placental vascular resistance. This review emphasizes the importance of considering geographic and environmental factors in pregnancy outcomes and calls for further research to better understand the mechanisms driving adverse outcomes at high altitude.

Objective: This study evaluates whether timing of amniotomy affects labor characteristics and maternal and neonatal outcomes in twin deliveries.

Methods: This retrospective study was conducted at a single academic medical center and included dichorionic diamniotic (DCDA) twin pregnancies with a normal anomaly scan and a vertex-presenting leading twin, delivered over a 7-year period. The cohort was divided into two groups: early amniotomy (performed at cervical dilation ≤3 cm) and late amniotomy (performed at >3 cm cervical dilation). Exclusion criteria included monochorionic twin pregnancies and planned elective cesarean deliveries. Maternal demographics, delivery characteristics, and neonatal outcomes were compared between groups.

Results: Of 51 592 deliveries, 1196 were twins; 565 DCDA pregnancies met the inclusion criteria (early n = 279; late n = 286). Groups were similar in age, body mass index (kg/m²), comorbidities, and gestation. Nulliparity and intrapartum cesarean rates were more common in the early amniotomy group (56.6% vs. 29.4%; P < 0.001, 24.4% vs. 9.8%; P < 0.001, respectively). Induction and augmentation rates, rupture-to-delivery interval, second stage duration, intrapartum fever, and meconium were similar. Neonatal outcomes, including birthweight, 5-min Apgar <7, neonatal intensive care unit admission, and composite morbidity were comparable. On adjusted analysis, early amniotomy (adjusted odds ratio [aOR] 1.84; 95% confidence interval 1.09-3.1), nulliparity (aOR 5.60; 3.17-9.87), and previous cesarean (aOR 3.94; 1.32-11.77) increased cesarean risk, whereas epidural was protective (aOR 0.40; 0.24-0.67).

Conclusion: In DCDA twin labor, early amniotomy (≤3 cm) is associated with increased intrapartum cesarean, despite similar durations of labor and neonatal outcomes. Amniotomy timing should be individualized, with caution against routine early rupture.

Objective: A single oral dose of azithromycin (AZM) given during labor to women planning a vaginal delivery reduced maternal infections including sepsis, with a stronger effect in sub-Saharan Africa than South Asia. Since maternal infection contributes to labor dysfunction and postpartum hemorrhage (PPH), we evaluated the effect of AZM on the risk of PPH and blood transfusion.

Methods: This was an unplanned secondary analysis of the Azithromycin Prevention in Labor Use Study (A-PLUS) randomized controlled trial at eight sites in seven low- and middle-income countries in sub-Saharan Africa, South Asia, and Latin America. The population consisted of pregnant women in labor at ≥28 weeks' gestation in health facilities randomized to either 2 g AZM or placebo. Based on an intent-to-treat analysis, the risk of PPH and blood transfusion was compared between AZM and placebo arms using Poisson regression adjusting for arm and site as fixed effects. The main outcome measures were (1) PPH (500 mL or greater) after delivery; and (2) postpartum blood transfusion after delivery.

Results: A total of 29 278 participants were randomized to APLUS; 14 590 to AZM and 14 688 to placebo. The risk of PPH did not significantly differ between AZM and placebo arms (1.4% in AZM; 1.6% in placebo; relative risk [RR] = 0.88; 95% confidence interval [CI]: 0.73, 1.07). The risk of blood transfusion also did not significantly differ between AZM and placebo arms (0.5% in AZM; 0.5% in placebo; RR = 0.90; 95% CI: 0.65, 1.25). There was also evidence indicating that the effect of AZM on the risk of blood transfusion, but not PPH, was beneficial in sub-Saharan Africa but not in South Asia (P value for two-way interaction = 0.002).

Conclusion: A single intrapartum oral dose of AZM did not significantly reduce the overall risk of PPH or blood transfusion.

Clinicaltrials: gov Identifier: NCT03871491.

Objective: The randomized trial of azithromycin to reduce maternal and neonatal sepsis (the A-PLUS Trial) found substantial reduction in maternal sepsis among women receiving azithromycin and substantial non-study antibiotic use. This secondary analysis explored the effect modification of non-study antibiotics on azithromycin versus placebo on maternal and newborn infection among A-PLUS participants.

Methods: Women ≥28 weeks gestation in labor and planning a vaginal delivery at a study hospital in seven low- and middle-income countries (Bangladesh, India [two sites], Pakistan, Guatemala, Kenya, Democratic Republic of Congo, and Zambia) were eligible for inclusion. Non-study antibiotic use was collected prospectively. We estimated the interaction of non-study antibiotics with azithromycin versus placebo on maternal and newborn sepsis.

Results: A total of 29 287 participants were randomized (14 590 to azithromycin; 14 688 to placebo). Maternal infection was reduced among the azithromycin group compared to placebo among those who did not receive non-study antibiotics, with estimated relative risk (RR) 0.58 (95% confidence interval [CI] 0.48, 0.70), and among those who received non-study antibiotics, with RR 0.80 (95% CI 0.70, 0.91). Similar results were observed for maternal sepsis. Neonatal infection was not significantly reduced in any group. These results were similar when stratified by African and Asian region but not statistically significant.

Conclusion: Our results suggest a benefit of azithromycin in reducing maternal infection or sepsis across all groups, with a larger reduction in risk among participants who had not received other antibiotics. Given the concerns of inappropriate use of antibiotics, further research is warranted to determine the most effective strategies of reducing risk of infection.

Objective: The aim of this study is to predict the severity of preeclampsia (PE) using the microvascular flow (MV-Flow) imaging technique, to examine the placental microvascular structure of PE patients, and to evaluate whether placental microvascular findings are associated with adverse outcomes in PE.

Methods: This study was designed as a single-center, prospective observational study including a total of 90 patients, comprising 30 cases of PE and 60 healthy pregnant women. Placental microvascularization was evaluated using MV-Flow imaging technology in both groups, and the vascular index (VI^mv) was automatically calculated for each patient. First, the perinatal outcomes of patients with PE and healthy controls were compared, followed by subgroup analyses comparing non-severe versus severe PE and early-onset (<34 weeks) versus late-onset (≥34 weeks) PE.

Results: In the preeclampsia group, placental VI^mv values were lower compared to the control group at all gestational ages (P < 0.001). There were more preterm births (P < 0.001) and more admissions to the neonatal intensive care unit in the preeclampsia group (P < 0.001). In the subgroup analysis, placental VI^vm was found to be lower in severe PE patients (P = 0.012). Low placental VI^vm values in patients with preeclampsia were associated with disease severity, preterm delivery, and neonatal intensive care unit admission.

Conclusion: By applying MV-Flow imaging technology in patients with PE, we demonstrated that in vivo placental vascularity was reduced compared to healthy pregnancies. The ease of clinical applicability and high efficiency of this ultrasound-based technology might provide preliminary insight into identifying patients at higher risk of severe disease and adverse perinatal outcomes in patients with preeclampsia.

Unsafe abortion remains a major public health and human rights challenge in Latin America, despite recent reforms that have expanded the legal grounds for abortion in several countries. A central reason for the persistent gap between law and access is the region's widespread reliance on physician-exclusive provider models, which structurally limit the availability of services, particularly in rural, Indigenous, and primary-care settings where specialists are scarce. Task sharing in abortion care should be understood not as a discretionary efficiency strategy, but as an essential component of States' obligations under legal rights to health care, equality, life, and scientific progress. A review of global evidence, a comparative analysis of legal and regulatory frameworks in 14 countries, and an in-depth examination of emerging reforms in Mexico, Colombia, Argentina, and Ecuador show that expanding provider eligibility is both clinically safe and normatively required. The conclusion outlines a regional reform agenda for aligning domestic regulations with World Health Organization standards.