Effect of intraovarian platelet-rich plasma injection on IVF outcomes in women with poor ovarian response: the PROVA randomized controlled trial.

STUDY QUESTION: Does intraovarian platelet-rich plasma (PRP) injection increase the number of mature oocytes obtained after controlled ovarian stimulation (COS) in young women with poor ovarian response (POR) undergoing IVF? SUMMARY ANSWER: Intraovarian PRP injection procedure does not improve mature oocyte yield after COS in women less than 38 years old with an established IVF history of POR. WHAT IS KNOWN ALREADY: POR is frequently encountered among the infertile population and the number of women seeking infertility treatment related to POR is increasing. Effective treatment options for this patient population to conceive with autologous oocytes are lacking. Case series and cohort studies suggest that intraovarian PRP injection may improve follicular recruitment in women with premature ovarian insufficiency (POI) and POR, yet robust randomized studies have not been performed to date to determine the clinical utility of this intervention. STUDY DESIGN, SIZE, DURATION: This was a multi-center randomized controlled trial (RCT) conducted at university-affiliated reproductive centers in the USA and Turkey, between January 2020 and November 2022. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients who met inclusion criteria (<38 years old, two or more prior cycles with <3 oocytes retrieved; and without single gene disorders, prior ovarian surgery, endometriomas, BMI >35 kg/m2, or severe male factor infertility) were randomized to either the PRP or control group. Patients in both groups subsequently underwent COS, oocyte retrieval, ICSI, preimplantation genetic testing for aneuploidy (PGT-A), and single euploid embryo transfer. Number of metaphase II (MII) oocytes obtained was the primary outcome. Secondary outcomes included ovarian reserve tests (antral follicle count [AFC] and anti-Müllerian hormone [AMH]), blastocyst and euploid blastocyst yields, and sustained implantation. The study was powered to detect a difference of one mature oocyte obtained at oocyte retrieval. MAIN RESULTS AND THE ROLE OF CHANCE: In total, 83 patients met inclusion criteria and were randomized to receive autologous intraovarian PRP injection (n = 41) or to no intervention (n = 42). No significant differences were observed in number of MII oocytes retrieved per cycle (2.8 ± 2.4 vs 3.1 ± 3.3 in PRP vs control, respectively; P = 0.9), blastocysts (1.0 ± 1.3 vs 1.3 ± 2.1, P = 0.8), or euploid blastocysts (0.8 ± 1.1 vs 0.9 ± 1.6; P = 0.5). Similarly, no differences were observed in the likelihood of obtaining at least one euploid blastocyst (45% vs 37%, P = 0.4; relative risk [RR], 95% CI = 0.9, 0.6-1.2) or the rate of sustained implantation (31% vs 29%, P = 0.9; RR 1.0, 0.7-1.3). Posttreatment AFC (7.9 ± 4.5 vs 6.8 ± 4.8, P = 0.3) and AMH (0.99 ± 0.98 vs 0.7 ± 0.6, P = 0.2) were also not different between the groups. LIMITATIONS, REASONS FOR CAUTION: Results from this RCT may not be generalizable to other PRP preparations owing to heterogeneity and lack of standardization. The control groups did not undergo a sham ovarian injection, which would have been relevant had the results shown benefit of PRP injection. Only patients with POR were included in this study, and these results may not be generalizable to more severe diminution of ovarian reserve, as seen with POI. WIDER IMPLICATIONS OF THE FINDINGS: The intraovarian PRP injection procedure does not improve mature oocyte yield or other parameters of IVF outcome in women less than 38 years old with an established IVF history of POR. The results from this study do not support the use of intraovarian PRP injection in this population. STUDY FUNDING/COMPETING INTEREST(S): Departmental funds were used and no external funding was requested for this study. ES is a consultant for and receives grant funding from the Foundation for Embryonic Competence. All other authors have no conflict of interest to declare. TRIAL REGISTRATION NUMBER: Clinicaltrials.gov Registry Identifier: NCT04163640. TRIAL REGISTRATION DATE: 15 November 2019. DATE OF FIRST PATIENT'S ENROLMENT: 24 February 2020.

Intraovarian platelet-rich plasma injection and IVF outcomes in patients with poor ovarian response: a double-blind randomized controlled trial.

STUDY QUESTION: Does platelet-rich plasma (PRP) intraovarian injection increase the number of retrieved oocytes in successive ovarian punctions among patients with poor ovarian reserve (POR)? SUMMARY ANSWER: The injection of PRP increases the number of retrieved oocytes without increasing the quality of developed blastocysts. WHAT IS KNOWN ALREADY: Management of women with reduced ovarian response to stimulation is one of the significant challenges in reproductive medicine. Recently, PRP treatment has been proposed as an adjunct in assisted reproduction technology, with controversial results. STUDY DESIGN, SIZE, DURATION: This placebo-controlled, double-blind, randomized trial included 60 patients with POR stratified according to the POSEIDON classification groups 3 and 4. It was conducted to explore the efficacy and safety of intraovarian PRP injection. Patients were proposed to undergo three consecutive ovarian stimulations to accumulate oocytes and were randomized to receive either PRP or placebo during their first oocyte retrieval. Randomization was performed using computer-generated randomization codes. Double blinding was ensured so that neither the participant nor the investigators knew of the treatment allotted. All patients underwent three ovarian stimulations and egg retrieval procedures. ICSI was performed after a third ovarian puncture. The primary endpoint was the number of mature oocytes retrieved after PRP or placebo injection in successive ovarian punctures. PARTICIPANTS/MATERIALS, SETTING, METHODS: Sixty women (30-42 years) fulfilling inclusion criteria were randomized in equal proportions to the treatment or control groups. MAIN RESULTS AND THE ROLE OF CHANCE: The baseline demographic and clinical characteristics [age, BMI, anti-Müllerian hormone (AMH) levels] were comparable between the groups. Regarding the primary endpoint, the cumulative number (mean ± SEM) of retrieved mature oocytes was slightly higher in the treatment group: 10.45 ± 0.41 versus 8.91 ± 0.39 in the control group, respectively (95% CI of the difference 0.42-2.66; P = 0,008). The number of mature oocytes obtained among all patients increased in successive egg retrievals: 2.61 ± 0.33 (mean ± SEM) in punction 1 (P1), 3.85 ± 0.42 in P2, and 4.73 ± 0.44 in P3. However, the increase was higher among patients receiving the assessed PRP treatment. In P2, the number of retrieved mature oocytes was 4.18 ± 0.58 versus 3.27 ± 0.61 in controls (95% CI of the difference: -0.30 to 2.12; P = 0.138) and in P3, 5.27 ± 0.73 versus 4.15 ± 0.45 (95% CI of the difference: 0.12-2.12; P = 0.029). The mean ± SEM number of developed and biopsied blastocysts was 2.43 ± 0.60 in the control group and 1.90 ± 0.32 in the treatment group, respectively (P = 0.449). The mean number of euploid blastocysts was 0.81 ± 0.24 and 0.81 ± 0.25 in the control and treatment groups, respectively (P = 1.000). The percentages of patients with euploid blastocysts were 53.33% (16 out of 30) and 43.33% (13 out of 30) for patients in the control and treatment groups, respectively (Fisher's exact test P = 0.606). The overall pregnancy rate per ITT was 43% (26 out of 60 patients). However, the percentage of clinical pregnancies was higher in the control group (18 out of 30, 60%) than in the treatment group (8 out of 30, 27%) (P = 0.018). There was also a trend toward poorer outcomes in the treatment group when considering full-term pregnancies (P = 0.170). There were no differences between control and treatment groups regarding type of delivery, and sex of newborns. LIMITATIONS, REASONS FOR CAUTION: The mechanism of the potential beneficial effect of PRP injection on the number of retrieved oocytes is unknown. Either delivered platelet factors or a mechanical effect could be implicated. Further studies will be needed to confirm or refute the data presented in this trial and to specify the exact mechanism of action, if any, of PRP preparations. WIDER IMPLICATIONS OF THE FINDINGS: The increasing number of women with a poor response to ovarian stimulation supports the exploration of new areas of research to know the potential benefits of therapies capable of increasing the number of oocytes available for fertilization and improving the quality of developed blastocysts. An increase in the retrieved oocytes in both arms of the trial suggests that, beyond the release of growth factor from platelets, a mechanical effect can play a role. However, neither improvement in euploid blastocyst development nor pregnancy rates have been demonstrated. STUDY FUNDING/COMPETING INTEREST(S): This trial was supported by Basque Government and included in HAZITEK program, framed in the new Euskadi 2030 Science and Technology Plan (PCTI 2030). These aids are co-financed by the European Regional Development Fund (FEDER). The study funders had no role in the study design, implementation, analysis, manuscript preparation, or decision to submit this article for publication. No competing interests are declared by all the authors. TRIAL REGISTRATION NUMBER: Clinical Trial Number EudraCT 2020-000247-32. TRIAL REGISTRATION DATE: 3 November 2020. DATE OF FIRST PATIENT'S ENROLLMENT: 16 January 2021.

Follitropin delta combined with menotropin in patients at risk for poor ovarian response during in vitro fertilization cycles: a prospective controlled clinical study.

BACKGROUND: The maximum daily dose of follitropin delta for ovarian stimulation in the first in vitro fertilization cycle is 12 µg (180 IU), according to the algorithm developed by the manufacturer, and based on patient's ovarian reserve and weight. This study aimed to assess whether 150 IU of menotropin combined with follitropin delta improves the response to stimulation in women with serum antimullerian hormone levels less than 2.1 ng/mL. METHODS: This study involved a prospective intervention group of 44 women who received 12 µg of follitropin delta combined with 150 IU of menotropin from the beginning of stimulation and a retrospective control group of 297 women who received 12 µg of follitropin delta alone during the phase 3 study of this drug. The inclusion and exclusion criteria and other treatment and follow-up protocols in the two groups were similar. The pituitary suppression was achieved by administering a gonadotropin-releasing hormone (GnRH) antagonist. Ovulation triggering with human chorionic gonadotropin or GnRH agonist and the option of transferring fresh embryos or using freeze-all strategy were made according to the risk of developing ovarian hyperstimulation syndrome. RESULTS: Women who received follitropin delta combined with menotropin had higher estradiol levels on trigger day (2150 pg/mL vs. 1373 pg/mL, p < 0.001), more blastocysts (3.1 vs. 2.4, p = 0.003) and more top-quality blastocysts (1.8 vs. 1.3, p = 0.017). No difference was observed in pregnancy, implantation, miscarriage, and live birth rates after the first embryo transfer. The incidence of ovarian hyperstimulation syndrome did not differ between the groups. However, preventive measures for the syndrome were more frequent in the group using both drugs than in the control group (13.6% vs. 0.6%, p < 0.001). CONCLUSIONS: In women with serum antimullerian hormone levels less than 2.1 ng/mL, the administration of 150 IU of menotropin combined with 12 µg of follitropin delta improved the ovarian response, making it a valid therapeutic option in situations where ovulation triggering with a GnRH agonist and freeze-all embryos strategy can be used routinely. TRIAL REGISTRATION: U1111-1247-3260 (Brazilian Register of Clinical Trials, available at https://ensaiosclinicos.gov.br/rg/RBR-2kmyfm ).

The construction of machine learning-based predictive models for high-quality embryo formation in poor ovarian response patients with progestin-primed ovarian stimulation.

OBJECTIVE: To explore the optimal models for predicting the formation of high-quality embryos in Poor Ovarian Response (POR) Patients with Progestin-Primed Ovarian Stimulation (PPOS) using machine learning algorithms. METHODS: A retrospective analysis was conducted on the clinical data of 4,216 POR cycles who underwent in vitro fertilization (IVF) / intracytoplasmic sperm injection (ICSI) at Sichuan Jinxin Xinan Women and Children's Hospital from January 2015 to December 2021. Based on the presence of high-quality cleavage embryos 72 h post-fertilization, the samples were divided into the high-quality cleavage embryo group (N = 1950) and the non-high-quality cleavage embryo group (N = 2266). Additionally, based on whether high-quality blastocysts were observed following full blastocyst culture, the samples were categorized into the high-quality blastocyst group (N = 124) and the non-high-quality blastocyst group (N = 1800). The factors influencing the formation of high-quality embryos were analyzed using logistic regression. The predictive models based on machine learning methods were constructed and evaluated accordingly. RESULTS: Differential analysis revealed that there are statistically significant differences in 14 factors between high-quality and non-high-quality cleavage embryos. Logistic regression analysis identified 14 factors as influential in forming high-quality cleavage embryos. In models excluding three variables (retrieved oocytes, MII oocytes, and 2PN fertilized oocytes), the XGBoost model performed slightly better (AUC = 0.672, 95% CI = 0.636-0.708). Conversely, in models including these three variables, the Random Forest model exhibited the best performance (AUC = 0.788, 95% CI = 0.759-0.818). In the analysis of high-quality blastocysts, significant differences were found in 17 factors. Logistic regression analysis indicated that 13 factors influence the formation of high-quality blastocysts. Including these variables in the predictive model, the XGBoost model showed the highest performance (AUC = 0.813, 95% CI = 0.741-0.884). CONCLUSION: We developed a predictive model for the formation of high-quality embryos using machine learning methods for patients with POR undergoing treatment with the PPOS protocol. This model can help infertility patients better understand the likelihood of forming high-quality embryos following treatment and help clinicians better understand and predict treatment outcomes, thus facilitating more targeted and effective interventions.

GDF9His209GlnfsTer6/S428T and GDF9Q321X/S428T bi-allelic variants caused female subfertility with defective follicle enlargement.

BACKGROUND: Antral follicles consist of an oocyte cumulus complex surrounding by somatic cells, including mural granulosa cells as the inner layer and theca cells as the outsider layer. The communications between oocytes and granulosa cells have been extensively explored in in vitro studies, however, the role of oocyte-derived factor GDF9 on in vivo antral follicle development remains elusive due to lack of an appropriate animal model. Clinically, the phenotype of GDF9 variants needs to be determined. METHODS: Whole-exome sequencing (WES) was performed on two unrelated infertile women characterized by an early rise of estradiol level and defect in follicle enlargement. Besides, WES data on 1,039 women undergoing ART treatment were collected. A Gdf9Q308X/S415T mouse model was generated based on the variant found in one of the patients. RESULTS: Two probands with bi-allelic GDF9 variants (GDF9His209GlnfsTer6/S428T, GDF9Q321X/S428T) and eight GDF9S428T heterozygotes with normal ovarian response were identified. In vitro experiments confirmed that these variants caused reduction of GDF9 secretion, and/or alleviation in BMP15 binding. Gdf9Q308X/S415T mouse model was constructed, which recapitulated the phenotypes in probands with abnormal estrogen secretion and defected follicle enlargement. Further experiments in mouse model showed an earlier expression of STAR in small antral follicles and decreased proliferative capacity in large antral follicles. In addition, RNA sequencing of granulosa cells revealed the transcriptomic profiles related to defective follicle enlargement in the Gdf9Q308X/S415T group. One of the downregulated genes, P4HA2 (a collagen related gene), was found to be stimulated by GDF9 protein, which partly explained the phenotype of defective follicle enlargement. CONCLUSIONS: GDF9 bi-allelic variants contributed to the defect in antral follicle development. Oocyte itself participated in the regulation of follicle development through GDF9 paracrine effect, highlighting the essential role of oocyte-derived factors on ovarian response.

The efficacy of platelet rich plasma on women with poor ovarian response: a systematic review and meta-analysis.

BACKGROUND: Platelet-rich plasma (PRP) is a therapeutic approach that is gaining attention for its potential in the treatment of poor ovarian response. This meta-analysis aimed to systematically review and analyze clinical studies to evaluate the impact of PRP on poor responders undergoing ovarian stimulation for IVF. METHODS: A comprehensive search was conducted in electronic databases, including PubMed, Embase, Scopus, Web of Science, and the Cochrane Library to identify relevant studies published in English. The pooled data, such as pregnancy outcome, number of MII oocytes, number of transferable embryos, and ovarian reserve markers were analyzed using R version 4.2.3. RESULTS: A total of 10 trials were enrolled in the present meta-analysis. Following PRP treatment, live birth rate was found to be 16.6% (95% CI 8.8%-26.1%), while clinical pregnancy rate was observed to be 25.4% (95% CI 13.1%-39.9%). PRP pretreatment resulted in a higher number of MII oocytes (MD 1.073, 95% CI 0.720 to 1.427), a higher number of embryos (MD 0.946, 95% CI 0.569 to 1.323), a higher antral follicle count (MD 1.117; 95% CI 0.689 to 1.544), and the change of hormone levels. CONCLUSIONS: Among the studies evaluated in this review, PRP showed promising results in poor responder. Further research is required to clarify the potential role of PRP in female reproductive health.

What is the context? The incidence of poor ovarian response following ovarian stimulation ranges globally from 5.6% to 35.1%.Although various interventions have been implemented in patients with POR, there is a lack of empirical evidence demonstrating the superiority of any of these therapies over one another.Platelet-rich plasma, which is rich in growth factors that have been implicated in cellular growth, differentiation, angiogenesis, and tissue repair, is emerging as a promising therapeutic modality.Limited data determines the viability of PRP as an alternative therapy for POR patients, but further evidence is needed to quantify this effect.What is new? To the best of our knowledge, this is the first systematic review and meta-analysis that investigated the efficacy of PRP on women with POR, including ten trials and 876 patients.This review provides a comprehensive overview of the existing evidence on the utilization of PRP in poor responders, while also emphasizing the primary limitations in the literature and the necessity for future research based on evidence.What is the impact? Among the studies evaluated in this review, PRP showed a potential positive impact on the regulation of sex hormone levels, ovarian response, and pregnancy outcomes.

The effect of ovarian response parameters and the synergistic effect of assisted reproduction of poor ovarian response treated with platelet rich plasma: systematic review and meta-analysis.

BACKGROUND: Poor ovarian response (POR) patients often encounter cycle cancellation and egg retrieval obstacles in assisted reproductive technology. Platelet rich plasma (PRP) ovarian injection is a potential treatment method, but the treatment methods are different, and the treatment results are controversial. OBJECTIVE: This study adopts a systematic review and meta-analysis method based on clinical research to explore the efficacy and safety of PRP injection on POR. METHOD: The following databases were searched for research published before March 2023; Medline (via PubMed), Web of Science, Scopus, Cochrane Library, Embase, Cochrane Library, and China National Knowledge Infrastructure Database (CNKI). The literature was then screened by two independent researchers, who extracted the data and evaluated its quality. Research was selected according to the inclusion criteria, and its quality was evaluated according to the NOS standard Cohort study. The bias risk of the included study was assessed with STATE 14.0. RevMan 5.3 software was used for meta-analysis. MAIN RESULTS: Ten studies were included in the analysis, including 7 prospective cohort studies and 3 retrospective studies involving 836 patients. The results showed that after PRP treatment, follicle stimulating hormone (FSH) significantly decreased and anti-Mueller hormone (AMH) and luteinizing hormone (LH) significantly increased in POR patients, but estradiol did not change significantly; The number of antral follicles increased, and the number of obtaining eggs and mature oocytes significantly increased; The number of Metaphase type II oocytes, 2PN and high-quality embryos, and cleavage stage embryos significantly increased. In addition, the patient cycle cancellation rates significantly decreased. The rate of natural pregnancy assisted reproductive pregnancy and live birth increased significantly. Four reports made it clear that no adverse reactions were observed. CONCLUSION: PRP may have the potential to improve pre-assisted reproductive indicators in POR patients, increase the success rate of in vitro fertilization-embryo transfer (IVF-ET) in POR patients, and improve embryo quality, and may be beneficial to the pregnancy outcome. There is no obvious potential risk in this study, but further clinical support is still needed.

Live birth rates in in vitro fertilization cycles with five or fewer follicles.

PURPOSE: To evaluate live birth rates (LBRs) for in vitro fertilization (IVF) cycles with ≤5 follicles at trigger, with the goal of helping patients with low follicle counts decide whether to proceed to retrieval. METHODS: This is a retrospective cohort study from an urban, university-affiliated fertility center. All IVF cycles that yielded <10 oocytes between 2016 and 2020 were reviewed. Cycles were included if <5 follicles measuring >14 mm were verified on trigger day. The primary outcome was LBR per retrieval after fresh or frozen transfer. Secondary outcomes were number of oocytes, mature oocytes, 2-pronuclear zygotes (2-PNs), blastocysts for transfer/biopsy, and euploid blastocysts (if preimplantation genetic testing for aneuploidy (PGT-A) was used). RESULTS: 1502 cycles (900 with PGT-A) from 972 patients were included. Mean number of oocytes, mature oocytes, 2-PNs, blastocysts for transfer/biopsy, and euploid blastocysts differed by follicle number (p < 0.001). Across all age groups, there were differences in LBR associated with follicle number (p < 0.001). However, within age groups, not all results were significant. For example, for patients <35 years, LBR did not differ by follicle number and among patients 35-37 years; LBR with two or three follicles was lower than with five (p < 0.02). LBR for patients 35-40 years was <20% with 1-3 follicles and 25-40% with 4-5 follicles. LBR for patients >41 years was <5% with 1-3 follicles and <15% with 4-5 follicles. CONCLUSION: As expected, LBR is higher with more follicles. Providing patients with <5 follicles with specific data can help them weigh the emotional, physical, and financial costs of retrieval.

Significance of serum AMH and antral follicle count discrepancy for the prediction of ovarian stimulation response in Poseidon criteria patients.

PURPOSE: To determine the risk of not being a poor responder in ovarian stimulation (OS) for in vitro fertilization (IVF) when ovarian reserve markers are discordant-one falling within Poseidon's criteria normal range (e.g., anti-Müllerian hormone (AMH) ≥ 1.2 ng/mL or antral follicle count (AFC) ≥ 5), and the other in the poor ovarian reserve range. METHODS: A tri-center retrospective cohort study (2015-2017) involving women with discordant AMH and AFC values undergoing their first IVF/ICSI cycle using conventional OS (cOS, ≥ 150 IU/day of follicle-stimulating hormone). Discordant serum AMH and AFC values were defined according to Poseidon's criteria (AMH < 1.2 ng/mL and AFC ≥ 5 or AMH ≥ 1.2 ng/mL and AFC < 5). Poor ovarian response (POR) was < 4 retrieved oocytes. Receiver operating characteristic (ROC) curves were used to determine AMH and AFC cut-offs for non-POR. Logistic regression analysis evaluated factors associated with non-POR. RESULTS: Out of 8797 patients who underwent assessment with both AMH and AFC, 1172 (13.3%) exhibited discordant values. Of these, 854 (72.9%) had ≥ 4 oocytes retrieved. Within this group, 726 (85.0%) had "low" AMH values, whereas 128 (15.0%) had "low" AFCs. An AFC of 6 had 77% sensitivity and 52% specificity (AUC = 0.700), while AMH of 1.19 ng/mL had 31% sensitivity and 85% specificity (AUC = 0.492) for non-POR. AFC and the use of recombinant gonadotropins were positive predictors of non-POR. CONCLUSIONS: When serum AMH is < 1.19 ng/mL, but AFC is ≥ 6, there is a moderate likelihood of a non-POR during stimulation. Conversely, if AFC is < 5 but serum AMH is ≥ 1.19 ng/mL, the chances of non-POR are low. Among patients with discordant markers, AFC emerges as the primary predictor of oocyte yield.

The effects of flexible short protocol with gonadotropin-releasing hormone antagonist on preventing premature ovulation in poor responders.

PURPOSE: The proportion of patients with poor ovarian response (POR) is increasing, but effective treatment remains a challenge. To control the hidden peaks of luteinizing hormone (LH) and premature ovulation for poor responders, this study investigated the efficacy of flexible short protocol (FSP) with gonadotropin-releasing hormone antagonist (GnRH-ant) on trigger day. METHODS: The 662 cycles of POR patients were retrospectively analyzed. The cohort was divided into control and intervention groups. The intervention group (group A) with 169 cycles received a GnRH-ant given on trigger day. The control (group B) with 493 cycles received only FSP. The clinical outcomes of the two groups were compared. RESULTS: Compared with group B, with gonadotropin-releasing hormone antagonist (GnRH-ant) on trigger day in group A the incidences of spontaneous premature ovulation decreased significantly (2.37% vs. 8.72%, P < 0.05). The number of fresh embryo-transfer cycles was 45 in group A and 117 in group B. There were no significant differences in clinical outcomes, including implantation rate, clinical pregnancy rate, live birth rate and the cumulative live birth rate (12.0% vs. 9.34%; 22.22% vs. 21.93%; 17.78% vs. 14.91%; 20.51% vs. 20%, respectively; P > 0.05) between the two group. CONCLUSION: FSP with GnRH-ant addition on trigger day had no effect on clinical outcomes, but could effectively inhibit the hidden peaks of luteinizing hormone (LH) and spontaneous premature ovulation in POR. Therefore, it is an advantageous option for POR women.

Efficacy of intra-ovarian injection of autologous platelet-rich plasma in women with poor responders: a systematic review and meta-analysis.

CONTEXT: The effect of platelet-rich plasma (PRP) on ovarian reserve markers in poor ovarian response (POR) is challenging. AIM: This systematic review and meta-analysis was, therefore, designed to evaluate the effectiveness of intra-ovarian injection of autologous PRP on improving ovarian reserve markers and assisted reproductive technology (ART) outcomes in infertile women with POR. METHODS: A systematic search was conducted for the efficacy of intra-ovarian injection of autologous PRP on the improvement of ovarian reserve markers and ART outcomes in infertile women with POR. The methodological quality of the included studies was checked and eligible studies were included in the meta-analysis to find pooled results. Keywords were primary ovarian insufficiency, premature menopause, poor responder, poor ovarian response, diminished/decreased ovarian reserve, platelet-rich plasma, and intra-ovarian or a combination of them. The effect of PRP on fertility indices was evaluated using the standardized mean difference (SMD). The analysis was performed through STATA version 13. KEY RESULTS: 13 studies containing 1289 patients were included. Mean age, body mass index (BMI) and duration of infertility was 37.63 ± 2.66 years, 24 ± 1.23 kg/m2 and 4.79 ± 1.64 years, respectively. Most of the studies measured the outcomes 2-3/3 months after intra-ovarian injection of autologous PRP. The antral follicular count (AFC) after treatment by PRP is higher with an SMD of 0.95 compared to before treatment. The day 3 follicle-stimulating hormone (FSH) after treatment by PRP is lower with an SMD of - 0.25 compared to before treatment. The day 3 estradiol (E2) after treatment by PRP is higher with an SMD of 0.17 compared to before treatment. The anti-Mullerian hormone (AMH) after treatment by PRP is higher with an SMD of 0.44 compared to before treatment. The total oocytes number after treatment by PRP is higher with an SMD of 0.73 compared to before treatment. The number of MII oocytes after treatment by PRP is higher with an SMD of 0.63 compared to before treatment. The number of cleavage-stage embryos after treatment by PRP is higher with an SMD of 1.31 compared to before treatment. The number of day 5 embryo after treatment by PRP is higher with an SMD of 1.28 compared to before treatment. Pooled estimation of a meta-analysis of prevalence studies reported a prevalence of 22% for clinical pregnancy, 5% for spontaneous pregnancy and 21% for ongoing pregnancy following PRP therapy. CONCLUSION: Intra-ovarian injection of PRP improved ovarian reserve markers with increasing AFC, serum level of AMH and day 3 E2 and decreasing serum level of day 3 FSH. In addition, this treatment improved ART outcomes through the increasing of number total oocytes, number of MII oocytes, number of cleavage-stage embryos and number of day 5 embryos in POR women. IMPLICATIONS: Although treatment of POR women remains challenging, the use of intra-ovarian injection of autologous PRP in POR patients prior to IVF/ICSI cycles is a sign of new hope for increasing the success of IVF/ICSI. However, further well-organized, randomized controlled trials should be conducted to substantiate this result and recommend intra-ovarian injection of PRP as part of routine treatment in women with POR.

Nomogram to predict the probability of clinical pregnancy in women with poor ovarian response undergoing in vitro fertilization/ intracytoplasmic sperm injection cycles.

BACKGROUND: Poor ovarian response (POR) is associated with decreased clinical pregnancy rates, emphasizing the need for developing clinical prediction models. Such models can improve prognostic accuracy, personalize medical interventions, and ultimately enhance live birth rates among patients with POR. OBJECTIVE: This study aims to develop and validate a prognostic model for predicting clinical pregnancy outcomes in individuals with POR undergoing in vitro fertilization/ intracytoplasmic sperm injection (IVF/ICSI) cycles. METHODS: A retrospective cohort of 969 patients with POR undergoing fresh embryo transfer cycles at the Reproductive Center of Fujian Maternal and Child Health Center from January 2018 to January 2022 was included. The cohort was randomly divided into model (n = 678) and validation (n = 291) groups in a 7:3 ratio. A single-factor analysis was performed on the model group to identify variables influencing clinical pregnancy. Optimal variables were selected using LASSO regression, and a clinical prediction model was constructed using multivariate logistic regression analysis. The model's calibration and discrimination were assessed using receiver operating characteristic (ROC) and calibration curves, while the clinical utility was evaluated using decision curve analysis. RESULTS: Multivariate logistic regression analysis revealed that the age of the women (odds ratio [OR] 0.936, 95% confidence interval [CI] 0.898-0.976, P = 0.002), body mass index (BMI) ≤ 24 (OR 2.748, 95% CI 1.724-4.492, P < 0.001), antral follicle count (AFC) (OR 1.232, 95% CI 1.073-1.416, P = 0.003), anti-Müllerian hormone (AMH) (OR 1.67, 95% CI 1.178-2.376, P = 0.004), number of mature oocytes (OR 1.227, 95% CI 1.075-1.403, P = 0.003), number of embryos transferred (OR 1.692, 95% CI 1.132-2.545, P = 0.011), and transfer of high-quality embryos (OR 3.452, 95% CI 1.548-8.842, P = 0.005) were independent predictors of clinical pregnancy in patients with POR. According to the receiver operating characteristic (ROC) analysis, the prediction model exhibited an area under the curve (AUC) of 0.752 (0.714, 0.789) in the model group and 0.765 (0.708, 0.821) in the validation group. The clinical decision curve demonstrated that the model held maximum clinical utility in both cohorts when the threshold probability of clinical pregnancy ranged from 6-81% to 12-82%, respectively. CONCLUSION: Clinical pregnancy outcomes in patients with POR who underwent IVF/ICSI treatment were influenced by several independent factors, including the age of the women, BMI, AFC, AMH, number of mature oocytes, number of embryos transferred, and transfer of high-quality embryos. A clinical prediction model based on these factors exhibited favorable clinical predictive and applicative value. Therefore, this model can serve as a valuable tool for clinical prognosis, intervention, and facilitating personalized medical treatment.

Can ultrasound elastography be useful in the diagnosis of poor ovarian response?

OBJECTIVES: This study aims to compare the elastographic properties of the ovaries of patients with poor ovarian response (POR) with healthy controls by using real-time ultrasound tissue elastography and to investigate the predictive value of ovarian strain ratio (OSR) in the diagnosis of POR. MATERIALS AND METHODS: A cross-sectional study was conducted among infertility patients. OSR measurements of 46 women diagnosed with POR and 41 healthy controls with male infertility were performed by real-time ultrasound tissue elastography. Ovarian volume, OSR, antral follicle count (AFC), age, body mass index (BMI), anti-mullerian hormone (AMH), follicle stimulating hormone (FSH), and estradiol (E2) values, were compared between the groups. A receiver operating characteristic curve was used to compare the sensitivity and specificity of OSR, AFC, AMH, FSH, and E2 for POR diagnosis. RESULTS: Patients with POR were significantly older, had a lower duration of infertility, lower AMH, higher FSH, higher E2, lower AFC and ovarian volume (p < 0.01, p = 0.02, p < 0.01, p < 0.01, p < 0.01, p < 0.01, p < 0.01, respectively). The mean OSR of both ovaries was similar between the groups. For the diagnosis of POR, the sensitivity and specificity for AMH were 97.5% and 100%, for AFC were 86.7% and 97.6%; for FSH were 66.7% and 80.5%, for E2 were 53.3% and 90.2%, respectively. CONCLUSIONS: The significant independent predictors of the POR were AMH, AFC, and FSH, with no additional significant contribution from OSR. However, considering the relationship between POR and ovarian fibrosis, it is recommended to investigate this issue in more comprehensive studies.

[Mechanism of resveratrol in protecting ovary in poor ovarian response mice by regulating Hippo signaling pathway].

This study observed the protective effect of resveratrol(Res) on ovarian function in poor ovarian response(POR) mice by regulating the Hippo signaling pathway and explored the potential mechanism of Res in inhibiting ovarian cell apoptosis. Female mice with regular estrous cycles were randomly divided into a blank group, a model group, and low-and high-dose Res groups(20 and 40 mg·kg~(-1)), with 20 mice in each group. The blank group received an equal volume of 0.9% saline solution by gavage, while the model group and Res groups received suspension of glycosides of Triptergium wilfordii(GTW) at 50 mg·kg~(-1) by gavage for two weeks to induce the model. After modeling, the low-and high-dose Res groups were continuously treated with drugs by gavage for two weeks, while the blank group and the model group received an equal volume of 0.9% saline solution by gavage. Ovulation was induced in all groups on the day following the end of treatment. Finally, 12 female mice were randomly selected from each group, and the remaining eight female mice were co-housed with male mice at a ratio of 1∶1. Changes in the estrous cycle of mice were observed using vaginal cytology smears. The number of ovulated eggs, ovarian wet weight, ovarian index, and pregnancy rate of mice were measured. The le-vels of anti-Mullerian hormone(AMH), follicle-stimulating hormone(FSH), estradiol(E_2), and luteinizing hormone(LH) in serum were determined using enzyme-linked immunosorbent assay(ELISA). Ovarian tissue morphology and ovarian cell apoptosis were observed using hematoxylin-eosin(HE) staining and terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL) staining, respectively. The protein expression levels of yes-associated protein(YAP) 1 and transcriptional coactivator with PDZ-binding motif(TAZ) were detected by immunohistochemistry(IHC), while the changes in protein expression levels of mammalian sterile 20-like kinase(MST) 1/2, large tumor suppressor(LATS) 1/2, YAP1, TAZ, B-cell lymphoma-2(Bcl-2), and Bcl-2 associated X protein(Bax) were determined by Western blot. The results showed that compared with the blank group, the model group had an increased rate of estrous cycle disruption in mice, a decreased number of normally developing ovarian follicles, an increased number of blocked ovarian follicles, increased ovarian granulosa cell apoptosis, decreased ovulation, reduced ovarian wet weight and ovarian index, increased serum FSH and LH levels, decreased AMH and E_2 levels, decreased protein expression levels of YAP1 and TAZ in ovarian tissues, increased relative expression levels of MST1/2, LATS1/2, and Bax proteins, and decreased relative expression levels of YAP1, TAZ, and Bcl-2 proteins. Additionally, the number of embryos per litter significantly decreased after co-housing. Compared with the model group, the low-and high-dose Res groups exhibited reduced estrous cycle disruption rates in mice, varying degrees of improvement in the number and morphology of ovarian follicles, reduced numbers of blocked ovarian follicles, improved ovarian granulosa cell apoptosis, increased ovulation, elevated ovarian wet weight and ovarian index, decreased serum FSH and LH levels, increased AMH and E_2 levels, elevated protein expression levels of YAP1 and TAZ in ovarian tissues, decreased relative expression levels of MST1/2, LATS1/2, and Bax proteins, and increased relative expression levels of YAP1, TAZ, and Bcl-2 proteins. Furthermore, the number of embryos per litter increased to varying degrees after co-housing. In conclusion, Res effectively inhibits ovarian cell apoptosis in mice and improves ovarian responsiveness. Its mechanism may be related to the regulation of key molecules in the Hippo pathway.

Eight weeks of androgen priming by daily low-dose hCG injections before ICSI treatment in women with low ovarian reserve.

STUDY QUESTION: Does 8 weeks of continuous low-dose hCG administration increase the proportion of antral follicles that reach the preovulatory state during ovarian stimulation (OS) in women with low ovarian reserve? SUMMARY ANSWER: The proportion of antral follicles (2-10 mm) that reached the preovulatory state did not increase. WHAT IS KNOWN ALREADY: The administration of androgens prior to OS might upregulate FSH receptor (FSHR) expression on granulosa cells, making follicles more responsive to exogenous FSH stimulation during OS. LH and hCG stimulate the local follicular androgen synthesis in theca cells and may be used as an endogenous androgen priming method. Exogenous priming by testosterone and dehydroepiandrosterone (DHEA) have been shown to increase the number of retrieved oocytes and live birth rate but the studies are small, and their use is associated with side effects. STUDY DESIGN, SIZE, DURATION: A prospective, paired, non-blinded single-center study including 20 women serving as their own controls conducted between January 2021 and July 2021 at The University Hospital Copenhagen Rigshospitalet, Denmark. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants underwent two identical consecutive IVF/ICSI treatments, a Control cycle and a Study cycle, separated by ∼8 weeks (two menstrual cycles) of daily injections of 260 IU recombinant hCG (rhCG). A freeze-all strategy was applied in the Control cycle. Both IVF/ICSI cycles were performed in a fixed GnRH antagonist protocol using a daily dose of 300 IU recombinant FSH (rFSH) and GnRH antagonist 0.25 mg from stimulation days 5-6. MAIN RESULTS AND THE ROLE OF CHANCE: Follicular output rate, defined as the number of follicles >16 mm on hCG trigger day divided by the antral follicle count (2-10 mm) at baseline, did not increase after 8 weeks of hCG priming (P = 0.8). The mean number of oocytes retrieved was significantly higher after the hCG priming being 4.7 (2.8) vs 3.2 (1.7) in the Study and Control cycle, respectively (P = 0.01). The duration of stimulation was longer in the Study versus the Control cycle (P = 0.05), despite the use of identical hCG trigger criterion and similar diameters of the three biggest follicles on hCG trigger day in the two cycles (P = 0.9). LIMITATIONS, REASONS FOR CAUTION: The sample size was small, and the number of oocytes retrieved was not the primary endpoint. Larger studies are needed to confirm this finding. WIDER IMPLICATIONS OF THE FINDINGS: Long-term, low-dose rhCG administration may increase the number of oocytes retrieved during IVF/ICSI in women with low ovarian reserve, but more research is needed before firm conclusions can be drawn. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by an unrestricted grant from Gedeon Richter. A.P. reports personal consulting fees from PregLem SA, Novo Nordisk A/S, Ferring Pharmaceuticals A/S, Gedeon Richter Nordics AB, Cryos International, and Merck A/S outside the submitted work and payment or honoraria for lectures from Gedeon Richter Nordics AB, Ferring Pharmaceuticals A/S, Merck A/S, and Theramex and Organon & Co. Grants to the institution have been provided by Gedeon Richter Nordics AB, Ferring Pharmaceuticals A/S, and Merck A/S and receipt of equipment by the institution from Gedeon Richter Nordics AB is reported. The remaining authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Identifier: NCT04643925.

Routine double-ovarian-stimulation (DuoStim) in poor responders lacks rationale, evidence, and follow-up.

Double ovarian stimulation (DuoStim), initially only suggested for fertility preservation in cancer patients, is now increasingly also used in routine clinical IVF, especially in poor responders. The claimed rational for this is the alleged existence of multiple follicular waves in a single intermenstrual interval, allowing for retrieval of more oocytes in a single IVF cycle. This commentary argues that this expansion of purpose lacks rationale, evidence, and follow-up. Consequently, we suggest that, unless valid clinical indications have been established, DuoStim be only subject of controlled clinical trials with appropriate experimental consents.

Androgen and inhibin B levels during ovarian stimulation before and after 8 weeks of low-dose hCG priming in women with low ovarian reserve.

STUDY QUESTION: Does 8 weeks of daily low-dose hCG administration affect androgen or inhibin B levels in serum and/or follicular fluid (FF) during the subsequent IVF/ICSI cycle in women with low ovarian reserve? SUMMARY ANSWER: Androgen levels in serum and FF, and inhibin B levels in serum, decreased following 8 weeks of hCG administration. WHAT IS KNOWN ALREADY: Recently, we showed that 8 weeks of low-dose hCG priming, in between two IVF/ICSI treatments in women with poor ovarian responder (anti-Müllerian hormone (AMH) <6.29 pmol/l), resulted in more follicles of 2-5 mm and less of 6-10-mm diameter at the start of stimulation and more retrieved oocytes at oocyte retrieval. The duration of stimulation and total FSH consumption was increased in the IVF/ICSI cycle after priming. Hypothetically, hCG priming stimulates intraovarian androgen synthesis causing upregulation of FSH receptors (FSHR) on granulosa cells. It was therefore unexpected that antral follicles were smaller and the stimulation time longer after hCG priming. This might indicate a different mechanism of action than previously suggested. STUDY DESIGN, SIZE, DURATION: Blood samples were drawn on stimulation day 1, stimulation days 5-6, trigger day, day of oocyte retrieval, and oocyte retrieval + 5 days in the IVF/ICSI cycles before and after hCG priming (the control and study cycles, respectively). FF was collected from the first aspirated follicle on both sides during oocyte retrieval in both cycles. The study was conducted as a prospective, paired, non-blinded, single-center study conducted between January 2021 and July 2021 at a tertiary care center. The 20 participants underwent two identical IVF/ICSI treatments: a control cycle including elective freezing of all blastocysts and a study cycle with fresh blastocyst transfer. The control and study cycles were separated by 8 weeks (two menstrual cycles) of hCG priming by daily injections of 260 IU recombinant hCG. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women aged 18-40 years with cycle lengths of 23-35 days and AMH <6.29 pmol/l were included. Control and study IVF/ICSI cycles were performed in a fixed GnRH-antagonist protocol. MAIN RESULTS AND THE ROLE OF CHANCE: Inhibin B was lower on stimulation day 1 after hCG priming (P = 0.05). Dehydroepiandrosterone sulfate (DHEAS) was significantly lower on stimulation day 1 (P = 0.03), and DHEAS and androstenedione were significantly lower on stimulation days 5-6 after priming (P = 0.02 and P = 0.02) The testosterone level in FF was significantly lower in the study cycle (P = 0.008), while the concentrations of inhibin B and androstenedione in the FF did not differ between the study and control cycles. A lower serum inhibin B in the study cycle corresponds with the antral follicles being significantly smaller after priming, and this probably led to a longer stimulation time in the study cycle. This contradicts the theory that hCG priming increases the intraovarian androgen level, which in turn causes more FSHR on developing (antral up to preovulatory) follicles. However, based on this study, we cannot rule out that an increased intra-follicular androgen level was present at initiation of the ovarian stimulation, without elevating the androgen level in serum and that an increased androgen level may have rescued some small antral follicles that would have otherwise undergone atresia by the end of the previous menstrual cycle. We retrieved significantly more oocytes in the Study cycle, and the production of estradiol per follicle ≥10-mm diameter on trigger day was comparable in the study and control cycles, suggesting that the rescued follicles were competent in terms of producing oocytes and steroid hormones. LIMITATIONS, REASONS FOR CAUTION: The sample size was small, and the study was not randomized. Our study design did not allow for the measurement and comparison of androgen levels or FSHR expression in small antral follicles before and immediately after the hCG-priming period. WIDER IMPLICATIONS OF THE FINDINGS: The results make us question the mechanism of action behind hCG priming prior to IVF. It is important to design a study with the puncture of small antral follicles before and immediately after priming to investigate the proposed hypothesis. Improved cycle outcomes, i.e. more retrieved oocytes, must be confirmed in a larger, preferably randomized study. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by an unrestricted grant from Gedeon Richter awarded to the institution. A.P. reports personal consulting fees from PregLem SA, Novo Nordisk A/S, Ferring Pharmaceuticals A/S, Gedeon Richter Nordics AB, Cryos International, and Merck A/S outside the submitted work and payment or honoraria for lectures from Gedeon Richter Nordics AB, Ferring Pharmaceuticals A/S, Merck A/S, and Theramex and Organon & Co and payment for participation in an advisory board for Preglem. Grants to the institution have been provided by Gedeon Richter Nordics AB, Ferring Pharmaceuticals A/S, and Merck A/S, and equipment and travel support has been given to the institution by Gedeon Richter Nordics AB. The remaining authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Identifier: NCT04643925.

TEAS, DHEA, CoQ10, and GH for poor ovarian response undergoing IVF-ET: a systematic review and network meta-analysis.

BACKGROUND: Assisted reproductive technology (ART) has brought good news to infertile patients, but how to improve the pregnancy outcome of poor ovarian response (POR) patients is still a serious challenge and the scientific evidence of some adjuvant therapies remains controversial. AIM: Based on previous evidence, the purpose of this systematic review and network meta-analysis was to evaluate the effects of DHEA, CoQ10, GH and TEAS on pregnancy outcomes in POR patients undergoing in vitro fertilization and embryo transplantation (IVF-ET). In addition, we aimed to determine the current optimal adjuvant treatment strategies for POR. METHODS: PubMed, Embase, The Cochrane Library and four databases in China (CNKI, Wanfang, VIP, SinoMed) were systematically searched up to July 30, 2022, with no restrictions on language. We included randomized controlled trials (RCTs) of adjuvant treatment strategies (DHEA, CoQ10, GH and TEAS) before IVF-ET to improve pregnancy outcomes in POR patients, while the control group received a controlled ovarian stimulation (COS) regimen only. This study was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The surface under the cumulative ranking curve (SUCRA) was used to provide a pooled measure of cumulative ranking for each outcome. RESULTS: Sixteen RCTs (2323 women) with POR defined using the Bologna criteria were included in the network meta-analysis. Compared with the control group, CoQ10 (OR 2.22, 95% CI: 1.05 to 4.71) and DHEA (OR 1.92, 95% CI: 1.16 to 3.16) had obvious advantages in improving the clinical pregnancy rate. CoQ10 was the best in improving the live birth rate (OR 2.36, 95% CI: 1.07 to 5.38). DHEA increased the embryo implantation rate (OR 2.80, 95%CI: 1.41 to 5.57) and the high-quality embryo rate (OR 2.01, 95% CI: 1.07 to 3.78) and number of oocytes retrieved (WMD 1.63, 95% CI: 0.34 to 2.92) showed a greater advantage, with GH in second place. Several adjuvant treatment strategies had no significant effect on reducing the cycle canceling rate compared with the control group. TEAS was the least effective of the four adjuvant treatments in most pooled results, but the overall effect appeared to be better than that of the control group. CONCLUSION: Compared with COS regimen, the adjuvant use of CoQ10, DHEA and GH before IVF may have a better clinical effect on the pregnancy outcome of POR patients. TEAS needs careful consideration in improving the clinical pregnancy rate. Future large-scale RCTs with direct comparisons are needed to validate or update this conclusion. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42022304723.

Higher live birth rate following transdermal testosterone pretreatment in poor responders: a systematic review and meta-analysis.

A systematic review and meta-analysis was performed aiming to identify good-quality randomized controlled trials (RCT) evaluating testosterone pretreatment in poor responders. Eight RCTs were analysed, evaluating 797 women. Transdermal testosterone gel was used in all studies, with a dose ranging from 10 to 12.5 mg/day for 10-56 days. The main outcome measure was achievement of pregnancy, expressed as clinical pregnancy or live birth. Testosterone pretreatment was associated with a significantly higher live birth (risk ratio [RR] 2.07, 95% confidence interval [CI] 1.09-3.92) and clinical pregnancy rate (RR 2.25, 95% CI 1.54-3.30), as well as a significant increase in the number of cumulus-oocyte complexes retrieved. Significantly fewer days to complete ovarian stimulation, a lower total dose of gonadotrophins, a lower cancellation rate due to poor ovarian response and a thicker endometrium on the day of triggering of final oocyte maturation were observed. No significant differences were observed in oestradiol concentration, the numbers of follicles ≥17 mm, metaphase II oocytes, two-pronuclear oocytes and embryos transferred, and the proportion of patients with embryo transfer. The current study suggests that the probability of pregnancy is increased in poor responders pretreated with transdermal testosterone who are undergoing ovarian stimulation for IVF.

Does follicular flushing increase oocyte number in poor responders? An update of a systematic review.

RESEARCH QUESTION: Does flushing of the follicles at ovum retrieval increase the number of retrieved oocytes in poor-response IVF patients? DESIGN: An update of an electronic literature search was performed to identify randomized controlled trials (RCT) investigating follicular flushing versus no flushing in women with a poor response to IVF treatment. No exclusion criteria for type of needle, stimulation or protocol were applied. A meta-analysis was conducted using the software RevMan 5.4. RESULTS: Six RCT were identified that had the primary objective of testing for an increase in mean number of cumulus-oocyte complexes or/and metaphase II oocytes between flushing and no flushing. A double-lumen needle was used in five trials, one study investigated a pseudo-double-lumen needle, and a conventional single-lumen needle was used in all the control groups. The main risk of bias in all the included studies is a lack of blinding of the physicians performing the puncture and incomplete data in four trials. A heterogeneity of direction and size of effect of follicular flushing on mean oocyte number retrieved was detected (I2 = 80, P = 0.0001), which precludes a synthesis of the data. Two studies showed a decrease or tendency towards a decrease in oocyte numbers, one study showed similar oocyte numbers, and one study showed a strong tendency towards increased oocyte numbers with flushing. A similar picture was seen for metaphase II oocytes (I2 = 73, P = 0.002). CONCLUSIONS: It is uncertain whether follicular flushing in poor-response IVF patients affects the number of retrieved oocytes. Larger pragmatic trials are warranted to clarify the effect of flushing on oocyte numbers and clinical outcomes in poor responders and monofollicular patients.