Single-cell proteomics reveals decreased abundance of proteostasis and meiosis proteins in advanced maternal age oocytes.

Advanced maternal age is associated with a decline in oocyte quality, which often leads to reproductive failure in humans. However, the mechanisms behind this age-related decline remain unclear. To gain insights into this phenomenon, we applied plexDIA, a multiplexed, single-cell mass spectrometry method, to analyze the proteome of oocytes from both young women and women of advanced maternal age. Our findings primarily revealed distinct proteomic profiles between immature fully grown germinal vesicle and mature metaphase II oocytes. Importantly, we further show that a woman's age is associated with changes in her oocyte proteome. Specifically, when compared to oocytes obtained from young women, advanced maternal age oocytes exhibited lower levels of the proteasome and TRiC complex, as well as other key regulators of proteostasis and meiosis. This suggests that aging adversely affects the proteostasis and meiosis networks in human oocytes. The proteins identified in this study hold potential as targets for improving oocyte quality and may guide future studies into the molecular processes underlying oocyte aging.

Personalized embryo transfer guided by endometrial receptivity analysis: a systematic review with meta-analysis.

STUDY QUESTION: Does a personalized embryo transfer (pET) guided by tests for endometrial receptivity (TER) increase the effectiveness of ART procedures? SUMMARY ANSWER: The use of TER-guided pET is not supported by current published evidence in women without repeated implantation failure (RIF), while in women with RIF more research is needed to assess a potential benefit. WHAT IS KNOWN ALREADY: Implantation rates are still far from ideal, especially in some patients that have RIF with good-quality embryos. As a potential solution, a wide range of diverse TER use different sets of genes to identify displacements of the window of implantation to adjust the individual length of progesterone exposure in a pET. STUDY DESIGN, SIZE, DURATION: A systematic review with meta-analysis was performed. Search terms included endometrial receptivity analysis, ERA, personalized embryo transfer. CENTRAL, PubMed, Embase, reference lists, clinical trials registers, and conference proceedings (search date October 2022) were searched, with no language restrictions. PARTICIPANTS/MATERIALS, SETTING, METHODS: Randomized controlled trials (RCTs) and cohort studies comparing a pET guided by TER vs standard embryo transfer (sET) in different subgroups that undergo ART were identified. We also investigated pET in non-receptive-TER vs sET in receptive-TER, and pET in a specific population vs sET in a general population. Risk of bias (RoB) was assessed with the Cochrane tool and ROBINS-I. Only those with low/moderate RoB underwent meta-analysis. The GRADE approach was used to evaluate the certainty of evidence (CoE). MAIN RESULTS AND THE ROLE OF CHANCE: We screened 2136 studies and included 35 (85% used ERA and 15% used other TER). Two studies were RCTs comparing endometrial receptivity analysis (ERA)-guided pET vs sET in women with no history of RIF. In women without RIF, no important differences (moderate-CoE) were found in live birth rates and clinical pregnancy rates (CPR). We also performed a meta-analysis of four cohort studies that were adjusted for confounding. In agreement with the RCTs, no benefits were found in women without RIF. However, in women with RIF, low CoE suggests that pET might improve the CPR (OR 2.50, 95% CI 1.42-4.40). LIMITATIONS, REASONS FOR CAUTION: We found few studies with low RoB. Only two RCTs in women without RIF were published, and none in women with RIF. Furthermore, the heterogeneity observed in populations, interventions, co-interventions, outcomes, comparisons, and procedures limited the pooling of many of the included studies. WIDER IMPLICATIONS OF THE FINDINGS: In the population of women without RIF, in agreement with previously published reviews, pET did not prove to be more effective than sET and, therefore, it precludes the routine use of this strategy in this population until more evidence is available. However, more research is advisable in women with RIF as low-certainty evidence from observational studies adjusted for confounders suggests that the CPR might be higher with pET guided by TER in this population. Although this review presents the best available evidence, it is still insufficient to change current policies. STUDY FUNDING/COMPETING INTEREST(S): No specific funding was obtained for this study. There are no conflicts of interest to declare. REGISTRATION NUMBER: PROSPERO CRD42022299827.

A freeze-all strategy does not increase live birth rates in women of advanced reproductive age.

RESEARCH QUESTION: Does a freeze-all strategy improve live birth rates in women of different age groups? DESIGN: Retrospective cohort study of 1882 first embryo transfer cycles, performed between January 2013 and December 2015. Reproductive outcomes between fresh (FRESH) or frozen (FROZEN) embryo transfers were compared in patients stratified by age: < 35, between 35 and 38, or > 38 years. Student's t test for independent samples and χ2 analyses were used as needed. A multivariable logistic regression analysis was performed adjusting for age, triggering drug, number of retrieved oocytes, number of transferred embryos, and percentage of top-quality embryos. MAIN RESULTS AND THE ROLE OF CHANCE: Live birth rates (LBR) were significantly higher for FROZEN in the < 35 years group (43.7% vs 24%; p < 0.001). In both the 35-38 and > 38 years groups, LBR for FROZEN vs FRESH were not statistically different (30.9% in the FROZEN group vs 29.3% in the FRESH group, p = 0.70, and 19.8% in the FROZEN group vs 12.7% in the FRESH group, p = 0.07, respectively). The multivariate analysis found a significantly positive effect of performing FROZEN on LBR in the younger group (OR 2.46, 95% CI 1.31-4.62; p = 0.005) but had no impact in women between 35 and 38 years (OR 1.01, 95% CI 0.55-1.83; p = 0.98) or older (OR 0.96, 95% CI 0.43-2.13; p = 0.92). CONCLUSIONS: Performing a freeze-all strategy seems to result in better reproductive outcomes when compared with a fresh ET in women under 35 years, with no significant impact on older women.

There is no evidence that the time from egg retrieval to embryo transfer affects live birth rates in a freeze-all strategy.

STUDY QUESTION: Does the time from ovum pick-up (OPU) to frozen embryo transfer (FET) affect reproductive outcomes in a freeze-all strategy? SUMMARY ANSWER: Our study did not detect statistically significant differences between first and subsequent cycles, clinically relevant differences are not ruled out and further and larger studies are required. WHAT IS KNOWN ALREADY: Following controlled ovarian hyperstimulation (COH) delaying FET until the endometrium has returned to an optimal pre-stimulation state may have a significant emotional impact on patients, which adds to the stress and anxiety accompanying a standard IVF cycle. Currently there is no agreement on the best time to perform a FET after a freeze-all cycle in order to maximize reproductive outcomes for the patient. STUDY DESIGN, SIZE, DURATION: Retrospective cohort study of 512 freeze-all cycles, performed between January 2012 and December 2014. COH was performed by either a GnRH antagonist (n = 397) or a long GnRH agonist protocol (n = 115). Ovulation was triggered using either a GnRH agonist (n = 258) or hCG (n = 254). Endometrial preparation was performed in an artificial cycle by either oral (n = 238) or transdermal (n = 274) oestrogen. Differences were considered significant if P < 0.05. PARTICIPANTS/MATERIALS, SETTING, METHODS: Reproductive outcomes between FETs which took place either within the first menstrual cycle following OPU (Cycle 1; n = 263) or afterwards (Cycle ≥2; n = 249) were compared. Student's t-test for independent samples, Mann-Whitney U-test and Chi-square analysis were used where appropriate. A multivariable logistic regression analysis was performed adjusting for maternal age, drug used for ovulation trigger, number of retrieved oocytes, number of embryos obtained, day of embryonic development at transfer, number of embryos transferred and type of endometrial preparation. Differences were considered significant if P < 0.05. MAIN RESULTS AND THE ROLE OF CHANCE: Live birth rate (LBR) was significantly higher in FET performed during Cycle 1 vs Cycle ≥2 (37.6% vs 27.3%, respectively; P = 0.01) before adjusting for confounding factors. We found no difference for biochemical pregnancy (49.8% vs 43.8%; P = 0.17), clinical pregnancy (44.1% vs 36.1%; P = 0.07) or pregnancy loss (11.8% vs 16.1%; P = 0.16). A multivariable analysis found no impact of timing of elective FET on LBR (odds ratio, OR 0.73; 95% CI 0.49-1.08). The impact remained not significant after adjusting for number of retrieved oocytes, drug used for ovulation trigger (hCG vs GnRH agonist) and reason for cryopreservation. The factors that significantly affected LBR were: maternal age in both age categories (women between 35 and 40 years vs women below 35 years, OR 0.63, 95% CI 0.4-0.95; and women over 40 years vs women below 35 years, OR 0.34, 95% CI 0.2-0.7), day of embryonic development at transfer (day +4 vs +3; OR 1.7, 95% CI 1.1-2.8) and number of transferred embryos (OR 2.2, 95% CI 1.4-3.3) and oestrogen used for endometrial preparation (transdermal vs oral; OR 0.62, 95% CI 0.4-0.9). LIMITATIONS REASONS FOR CAUTION: The main limitation of our study is its retrospective nature. Although we adjusted our statistical analysis for a number of known and suspected confounders, we cannot exclude the possibility of residual confounding factors. WIDER IMPLICATIONS OF THE FINDINGS: According to our results, clinicians might not need to wait more than one menstrual cycle before performing FET. This allows us to reduce unnecessary delays in FET, without compromising reproductive outcomes. STUDY FUNDING/COMPETING INTERESTS: No funding was sought for this study. Authors declare no competing interests. TRIAL REGISTRATION NUMBER: NA.

Nifedipine versus fenoterol in the management of preterm labor: a randomized, multicenter clinical study.

PURPOSE: To compare the efficacy of nifedipine and fenoterol in the management of threatened preterm labor (TPL). METHODS: A randomized and multicenter study assessing the tocolytic effect of nifedipine versus fenoterol in patients admitted to the participating maternity units with a diagnosis of TPL and a cost-savings study for economic assessment. For a power of 80% and an α error equal to 0.05, 132 consecutive patients were recruited during the study period; 66 patients were assigned to each group. A χ(2) analysis and a mean differences test were performed according to variable types and survival curves per intention-to-treat. RESULTS: Demographics were similar in both groups. The latency period was similar in both groups (26.7 vs. 25.6; p = 0.3). There were no differences in the results obtained. Nifedipine failed more frequently to obtain tocolysis when used as a first-line agent (80 vs. 90%, p = 0.0001). The group treated with fenoterol showed more drug adverse events (57.8 vs. 19.0%, p = 0.0001). The economic assessment did not evidence a significant difference in terms of cost savings between groups treated with either drug. CONCLUSION: The present study failed to demonstrate either clinical or economic superiority of any of the two drugs used in TPL management. The highest failure percentage of nifedipine when used as a first-line agent should encourage further research.

Local infiltration of gonyautoxin is safe and effective in treatment of chronic tension-type headache.

BACKGROUND: Gonyautoxin are phycotoxins, whose molecular mechanism of action is a reversible block of the voltage-gated sodium channels at axonal level, impeding nerve impulse propagation. OBJECTIVE: To evaluate clinical efficacy of gonyautoxin in the treatment of patients with chronic tensional-type headache. METHODS: Open trial from September 2004 to 2005 in Hospital Clínico Universidad de Chile. Twenty-seven patients with chronic tension-type headache were locally infiltrated with gonyautoxins (50 micrograms) in ten sites considered as pain trigger points in a fixed infiltration protocol. In each site, a volume of 200 microlitres was injected. EMG recording was performed before and immediately after infiltrations. Main outcome measures are where a significantly drop-off in acute headache pain score occurs and number of days without headache pain. RESULTS: No side effects were detected in the follow-up period. From base line of 2 weeks, 19 patients of 27 (70%) are the successfully responders to the treatment. They showed the remarkable immediate effect after infiltration demonstrated by trapezium EMG recording. Patients reported a fall in pain score 5 minutes post-injection from 5.0 +/- 2.8 to 1.6 +/- 1.6 (mean +/- SD). The responder showed an average of 8.1 +/- 9.9 weeks of headache pain-free, all of them without a second infiltration or use of any additional analgesic medication. DISCUSSION: The therapeutic properties of gonyautoxin local infiltration in chronic tension-type headache patients are shown to be safe and effective. This report describes a new therapy for chronic tension-type headache involving local infiltrations of gonyautoxins. The immediate headache pain relief effect shown only minutes after toxin infiltrations were the most remarkable feature of this protocol. This is the first gonyautoxins testing report in the treatment of chronic tension-type headache.