BACKGROUND

Managing low ovarian response remains challenging despite advancements in assisted reproductive technology (ART). Although several approaches have been proposed, there is no strong evidence that a particular stimulation protocol is superior over the other in terms of improving reproductive outcomes in this group of women. The double stimulation protocol (DuoStim) suggests ovarian stimulation during both the follicular phase and the luteal phase of the same ovarian cycle; hence, facilitating two oocyte retrievals in the shortest amount of time.

This study assessed the effect of the double stimulation protocol (DuoStim) on poor ovarian responders in terms of cumulative live birth rates and clinical pregnancy rates, and compared these outcomes to conventional stimulation protocols.

This is a systematic review and meta-analysis of randomized controlled trials (RCT), cohort and cross-sectional studies in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement. Data from eligible journals were tabulated and analyzed using Cochran’s Q and I² tests.

Eight studies involving poor ovarian responders were included in the meta-analysis. Pooled analysis demonstrated no significant difference between DuoStim and conventional ovarian stimulation protocols in clinical pregnancy rate (OR 0.99, 95% CI 0.75–1.30) and cumulative live birth rate (OR 0.87, 95% CI 0.59–1.28). Fertilization rates were likewise comparable between groups. Nevertheless, several included studies reported higher oocyte yield and greater numbers of mature oocytes and blastocysts with DuoStim

Current evidence does not demonstrate significant superiority of DuoStim over conventional ovarian stimulation protocols in terms of clinical pregnancy rates, cumulative live birth rates, or fertilization rates among poor ovarian responders. However, DuoStim appears to be an effective strategy for increasing oocyte yield within a shorter treatment timeframe. Its use may be particularly relevant in selected patients with diminished ovarian reserve, advanced maternal age, or urgent fertility preservation needs. Further high-quality prospective trials are warranted to clarify its impact on reproductive outcomes.

BACKGROUND

The benefits of preimplantation genetic testing for aneuploidy (PGT-A) in the advanced maternal age group are unclear.

This study aims to determine whether PGT-A improves pregnancy outcomes.

This is a retrospective cohort study of PGT-A outcomes using next generation sequencing for advanced maternal age women undergoing IVF at CARMI from May 2017 to May 2021. Women were grouped by age: those 35-39 and those 40 and above. Pregnancy rate (PR), live birth rate (LBR), and miscarriage rate (MR) were computed per transfer and per cycle and compared with women who underwent single day-5 frozen transfer of a morphologically chosen embryo.

Overall euploid blastocyst rate was 38.5%: 16.9% for 40 and above and 47.6% for 35- 39 group. There were no transfers in 41.4% due to absence of a euploid embryo. PR and LBR per embryo transfer were higher in the PGT-A versus the non-PGT-A group (61.9% vs 24.1% p = < 0.001 and 42.9% vs 19% p = < 0.001). By age, the findings were similar: higher PR and LBR per-embryo transfer in PGT-A versus non-PGT-A in the 35-39 group (58.4% and 29%, p = 0.006 and 42.9% vs 22.6%, p < 0.001 respectively) and 40 and above (71.4% vs 18.5%, p < 0.001 and 53.6% vs 14.8%, p < 0.001 respectively). MR was increased in the PGT-A versus non-PGT-A group, but this may be due to the small number of events in the population.

The study suggests an increase in PR and LBR per embryo transfer in advanced maternal age women undergoing PGT-A. A larger sample size is needed to validate the results.

Depression currently affects about 280 million people worldwide and its prevalence has been increasing dramatically, especially among the young and people of reproductive age, which consequently leads to an increase in antidepressant consumption. Antidepressants are associated with sexual dysfunction in both men and women; however, their role in male fertility has been scarcely studied. Fluoxetine and sertraline, two serotonin reuptake inhibitors (SSRIs), are among the most prescribed antidepressants worldwide. To determine their possible effects, human sperm cells were exposed to either sertraline or fluoxetine at concentrations previously found in blood and seminal fluid of patients undergoing treatment. Spermatozoa were incubated for up to 24 h at 37°C and 5% CO 2 , and important functional parameters such as sperm motility, viability, mitochondrial membrane potential, cellular reactive oxygen species (ROS) production, chromatin/DNA integrity, acrosome status, and tyrosine phosphorylation were assessed. At low levels, fluoxetine consistently decreased progressive motility throughout time while promoting fluctuations in ROS levels and sperm capacitation. Nevertheless, it did not affect viability, mitochondrial membrane potential, acrosome reaction nor chromatin/DNA integrity. Sertraline, on the other hand, had little to nonsignificant impact at low doses, but affected almost all tested parameters at supratherapeutic concentrations. Altogether, our results suggest that both antidepressants may impair sperm function, possibly through different mechanisms of action, but fluoxetine is the only exhibiting mild negative effects at doses found in vivo .
Humans ; Male ; Spermatozoa/drug effects* ; Fluoxetine/pharmacology* ; Sperm Motility/drug effects* ; Sertraline/pharmacology* ; Reactive Oxygen Species/metabolism* ; Antidepressive Agents/pharmacology* ; Membrane Potential, Mitochondrial/drug effects* ; Sperm Capacitation/drug effects* ; Selective Serotonin Reuptake Inhibitors/pharmacology* ; Cell Survival/drug effects* ; Acrosome Reaction/drug effects*

Nonobstructive azoospermia (NOA) is considered the most challenging clinical scenario for infertile men and current treatments leave many men unsuccessful at being able to achieve a pregnancy with their partner using their own sperm. Microdissection testicular sperm extraction (micro-TESE) is the choice for men with NOA desiring to father children with their own gametes. Micro-TESE results in the highest numbers of sperm cells retrieved for use with in vitro fertilization/intracytoplasmic sperm injection. With suboptimal micro-TESE success rates of sperm retrieval and then pregnancy and live birth using the retrieved sperm with in vitro fertilization/intracytoplasmic sperm injection, advances to improve outcomes are necessary. This article comprehensively reviews the technologies investigated to date to improve the outcomes for men undergoing micro-TESE.
Humans ; Male ; Sperm Retrieval ; Azoospermia/surgery* ; Pregnancy ; Female ; Sperm Injections, Intracytoplasmic ; Microdissection/methods* ; Fertilization in Vitro ; Testis/surgery*

Reactive oxygen species (ROS) play a dual role in mammalian spermatozoa. At high levels, they are detrimental to sperm function since they can promote oxidative stress that produces oxidation of protein, lipids, and sperm DNA. This oxidative damage is associated with male infertility. On the other hand, when ROS are produced at low levels, they participate in the redox signaling necessary for sperm capacitation. Capacitation-associated ROS are produced by the sperm oxidase, whose identity is still elusive, located in the plasma membrane of the spermatozoon. ROS, such as superoxide anion, hydrogen peroxide, nitric oxide, and peroxynitrite, activate protein kinases and inactivate protein phosphatases with the net increase of specific phosphorylation events. Peroxiredoxins (PRDXs), antioxidant enzymes that fight against oxidative stress, regulate redox signaling during capacitation. Among them, PRDX6, which possesses peroxidase and calcium-independent phospholipase A 2 (iPLA 2 ) activities, is the primary regulator of redox signaling and the antioxidant response in human spermatozoa. The lysophosphatidic acid signaling is essential to maintain sperm viability by activating the phosphatidylinositol 3-kinase/protein kinase (PI3K/AKT) pathway, and it is regulated by PRDX6 iPLA 2 , protein kinase C (PKC), and receptor-type protein tyrosine kinase. The understanding of redox signaling is crucial to pave the way for novel diagnostic tools and treatments of male infertility.
Humans ; Male ; Spermatozoa/physiology* ; Signal Transduction/physiology* ; Oxidation-Reduction ; Peroxiredoxins/physiology* ; Reactive Oxygen Species/metabolism* ; Oxidative Stress/physiology* ; Sperm Capacitation/physiology* ; Infertility, Male/metabolism*

Since the early days of assisted reproductive technology (ART), the importance of sperm processing, employed to separate the motile, morphologically normal sperm from the semen, has been shown to be beneficial. The aim of the semen processing technique has been to remove seminal plasma and facilitate capacitation. Additionally, the presence of leukocytes, bacteria, and dead spermatozoa has been shown to be detrimental as it may cause oxidative stress that has an adverse effect on oocyte fertilization and embryo development. Hence, removal of leukocytes, bacteria, and dead spermatozoa is an important step of sperm processing for assisted reproduction. Currently, several sperm processing techniques have been evolved and optimized in the field of assisted reproduction. The requirements for in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), and testicular sperm extraction (TESE) are different than those of intrauterine insemination (IUI). The yield of as many motile, morphologically normal sperm as possible is a prerequisite for the success of IVF insemination procedure. In ICSI, where injection of a single spermatozoon into the oocyte is performed by the embryologist, sperm selection techniques play a crucial role in the ICSI procedure. Finally, sperm retrieval in TESE samples with very low number of sperm may be challenging and requires extra care during sample processing. Additionally, sperm cryopreservation is necessary in TESE cases in order to avoid multiple biopsies.
Humans ; Sperm Injections, Intracytoplasmic/methods* ; Male ; Fertilization in Vitro/methods* ; Sperm Retrieval ; Andrology/methods* ; Cryopreservation ; Female ; Spermatozoa

The use of fresh versus frozen spermatozoa in men with nonobstructive azoospermia (NOA) undergoing in vitro fertilization (IVF) has been a debated hot topic among reproductive specialists. Each approach presents distinct advantages and disadvantages, with fresh sperm typically showing superior sperm quality, while frozen sperm offers logistical flexibility and a reliable backup for repeated cycles. This review summarizes the latest advancements in sperm retrieval and cryopreservation techniques, providing practitioners with a comprehensive analysis of each option's strengths and limitations. Comparative studies indicate that, although fresh sperm often has better quality metrics, cryopreservation methods such as vitrification have significantly improved postthaw outcomes, making frozen sperm a viable choice in assisted reproductive technologies (ART). The findings show comparable rates for fertilization, implantation, clinical pregnancy, and live birth between fresh and frozen microdissection testicular sperm extraction (micro-TESE) sperm in many cases, although patient-specific factors such as timing, cost-effectiveness, and procedural convenience should guide the final decision. Ultimately, the choice of using fresh or frozen sperm should align with the individual needs and conditions of patients. This tailored approach, supported by the latest advancements, can optimize ART outcomes and provide personalized reproductive care.
Humans ; Cryopreservation/methods* ; Male ; Sperm Retrieval ; Semen Preservation/methods* ; Azoospermia/therapy* ; Pregnancy ; Female ; Fertilization in Vitro ; Spermatozoa ; Microdissection ; Pregnancy Rate

OBJECTIVES: Chromosomal abnormalities are the most common cause of spontaneous abortion (SA). This study aims to analyze the association between SA and chromosomal abnormalities in products of conception, and to compare the impact of different pregnancy modes and different numbers of previous abortions on chromosomal abnormalities, providing clinical consulting references. METHODS: A total of 1 345 SA patients treated at the Affiliated Women's Hospital of Jiangnan University (Wuxi Maternity and Child Health Care Hospital) between January 2019 and December 2023 were enrolled. According to the mode of conception, patients were divided into 2 groups: a spontaneous pregnancy group (S group, n=1242) and an assisted reproductive technology (ART)-conceived group (ART group, n=103). Based on the number of miscarriages, the S group was further subdivided into a spontaneous sporadic abortion group (S-1 group, n=780) and a spontaneous recurrent abortion group (S-2 group, n=462); the ART group was subdivided into an ART sporadic abortion group (ART-1 group, n=68) and an ART recurrent abortion group (ART-2 group, n=35). Chromosomal microarray analysis (CMA) was performed on products of conception. RESULTS: The incidence of numerical chromosomal abnormalities was 56.79% (443/780) in the S-1 group and 52.38% (242/462) in the S-2 group, while the incidence of structural abnormalities was 4.36% (34/780) and 7.36% (34/462), respectively. There was a statistically significant difference in structural abnormalities between the 2 groups (P<0.05). Among the spontaneous pregnancy SA cases, the incidence of numerical abnormalities decreased with increasing numbers of miscarriages, and was significantly lower in the group with ≥4 miscarriages compared to those with 1 or 2 miscarriages (both P<0.05). The incidence of structural abnormalities in groups with 1, 2, 3, and ≥4 miscarriages was 3.46%, 5.65%, 5.88%, and 4.35%, respectively, with no statistically significant differences among groups (all P>0.05). The incidence of pathogenic copy number variants (pCNVs) plus likely pathogenic copy number variants (LP-CNVs) gradually increases in the group with 1-3 miscarriages, and there was a statistically significant difference between the group with 1 miscarriage and the group with 2 miscarriages (P<0.05). In the ART group, the incidence of numerical abnormalities was 47.06% (32/68) in ART-1 and 37.14% (13/35) in ART-2, while structural abnormalities occurred in 2.94% (2/68) and 11.43% (4/35), respectively, with no significant differences between the groups (both P>0.05). There were no statistically significant differences in the incidence of numerical or structural abnormalities between the S-1 and ART-1 groups, or between the S-2 and ART-2 groups (all P>0.05). CONCLUSIONS Chromosomal numerical and structural abnormalities are common in SA patients from both spontaneous and ART-conceived pregnancies. Attention should be paid to patients with recurrent miscarriage in genetic investigation.
Humans ; Female ; Pregnancy ; Chromosome Aberrations/statistics & numerical data* ; Abortion, Spontaneous/epidemiology* ; Adult ; Reproductive Techniques, Assisted/adverse effects* ; Abortion, Habitual/genetics* ; Fertilization

OBJECTIVES: Transcervical resection of adhesions (TCRA) under hysteroscopy is the mainstay treatment for intrauterine adhesions (IUA), but its effectiveness varies depending on the surgical approach. This study aims to investigate the impact of different surgical techniques on endometrial repair and pregnancy outcomes in patients with secondary infertility and moderate-to-severe IUA. METHODS: A retrospective analysis was conducted on 225 patients who underwent TCRA followed by in vitro fertilization and embryo transfer between January 2021 and December 2022. Patients were grouped based on the surgical method: A cold knife group (n=127) and an electrosurgical group (n=98). Adhesions were separated using either cold knife or electrosurgical instruments. Postoperative visualization of uterine angle and tubal ostia, endometrial restoration, vascular endothelial growth factor (VEGF) expression in adhesion tissues, and clinical pregnancy outcomes were compared. Univariate and multivariate Logistic regression analyses were performed to identify factors influencing pregnancy outcomes. A LightGBM model was constructed to predict pregnancy outcomes. RESULTS: Compared with the electrosurgical group, patients in the cold knife group had significantly greater postoperative endometrial thickness [(8.86±0.53) mm vs (8.10±0.87) mm, P<0.05], higher live birth rates (64.57% vs 30.61%, P<0.05), and lower VEGF expression (1.31±0.09 vs 1.53±0.16, P<0.05). Logistic regression analyses identified age, number of visible tubal ostia postoperatively, and surgical method as significant factors affecting pregnancy outcomes (P<0.05). The LightGBM model based on surgical method had an area under the curve (AUC) of 0.882 (0.838-0.926), with internal validation AUC of 0.817 (0.790-0.840). CONCLUSIONS Cold knife surgery promotes faster recovery of the endometrial microenvironment and earlier improvement of fertility in patients with secondary infertility and IUA Surgical method is a key factor influencing pregnancy outcomes, and the LightGBM model based on surgical approach shows good predictive performance for pregnancy outcomes in patients with moderate-to-severe IUA.
Humans ; Female ; Pregnancy ; Tissue Adhesions/surgery* ; Retrospective Studies ; Adult ; Pregnancy Outcome ; Uterine Diseases/surgery* ; Hysteroscopy/methods* ; Infertility, Female/etiology* ; Electrosurgery/methods* ; Fertilization in Vitro ; Endometrium/surgery* ; Embryo Transfer ; Vascular Endothelial Growth Factor A/metabolism*

OBJECTIVES: To explore the effects of exogenous trigger (hCG/GnRHa) versus endogenous LH surge in natural cycle IVF/ICSI (NC-IVF/ICSI) for patients with diminished ovarian reserve (DOR). METHODS: A retrospective analysis was conducted on 1,118 NC-IVF/ICSI cycles from two reproductive centers between 2013 and 2024. Propensity score matching (PSM) and multivariate logistic regression were used to adjust for confounding factors. The trigger-day hormone threshold was determined using receiver operating characteristic (ROC) curve analysis. Outcome measures included oocyte retrieval rate, 2PN fertilization rate, clinical available embryo rate, high-quality embryo rate, fresh cycle clinical pregnancy rate (CPR), and live birth rate (LBR). RESULTS: After adjusting for confounders via PSM and logistic regression, the exogenous trigger group demonstrated significantly better outcomes across all the evaluated parameters (oocyte retrieval rate, 2PN fertilization rate, transferable embryo rate, high-quality embryo rate, fresh cycle CPR, and LBR) than the endogenous LH surge group (P<0.05). Age-stratified analysis revealed that for the entire cohort, exogenous triggering significantly increased the number of transferable embryos and high-quality embryos (P<0.001). In the 35-39 years old subgroup, exogenous triggering showed significant advantages in oocyte yield, high-quality embryo rate, CPR, and LBR (P<0.05) and resulted in the most pronounced improvement in LBR (OR=6.25, 95% CI: 1.34-29.23). ROC analysis established a decision-day LH threshold of 19.055 mIU/mL (AUC=0.945, specificity=93.3%) for precise stratification of the clinical pathways. CONCLUSIONS For DOR patients undergoing NC-IVF/ICSI, exogenous triggering comprehensively improves the treatment outcomes, particularly providing significant live birth benefits for women aged 35-40 years. An individualized protocol incorporating the LH threshold (19.055 mIU/mL) effectively enhances embryonic developmental potential and live birth rates.
Humans ; Female ; Ovarian Reserve ; Pregnancy ; Propensity Score ; Retrospective Studies ; Fertilization in Vitro ; Sperm Injections, Intracytoplasmic ; Chorionic Gonadotropin ; Pregnancy Rate ; Logistic Models ; Ovulation Induction/methods* ; Gonadotropin-Releasing Hormone ; Adult ; Oocyte Retrieval