The ovarian response to gonadotropin stimulation varies widely among women, and could impact the probability of live birth as well as treatment risks. Many studies have evaluated the impact of different gonadotropin starting doses, mainly based on predictive variables like ovarian reserve tests (ORT) including anti-Müllerian hormone (AMH), antral follicle count (AFC), and basal follicle-stimulating hormone (bFSH). A Cochrane systematic review revealed that individualizing the gonadotropin starting dose does not affect efficacy in terms of ongoing pregnancy/live birth rates, but may reduce treatment risks such as the development of ovarian hyperstimulation syndrome (OHSS). An individual patient data meta-analysis (IPD-MA) offers a unique opportunity to develop and validate a universal prediction model to help choose the optimal gonadotropin starting dose to minimize treatment risks without affecting efficacy.The objective of this IPD-MA is to develop and validate a gonadotropin dose-selection model to guide the choice of a gonadotropin starting dose in IVF/ICSI, with the purpose of minimizing treatment risks without compromising live birth rates.Electronic databases including MEDLINE, EMBASE, and CRSO were searched to identify eligible studies. The last search was performed on 13 July 2022. Randomized controlled trials (RCTs) were included if they compared different doses of gonadotropins in women undergoing IVF/ICSI, presented at least one type of ORT, and reported on live birth or ongoing pregnancy. Authors of eligible studies were contacted to share their individual participant data (IPD). IPD and information within publications were used to determine the risk of bias. Generalized linear mixed multilevel models were applied for predictor selection and model development.A total of 14 RCTs with data of 3455 participants were included. After extensive modeling, women aged 39 years and over were excluded, which resulted in the definitive inclusion of 2907 women. The optimal prediction model for live birth included six predictors: age, gonadotropin starting dose, body mass index, AFC, IVF/ICSI, and AMH. This model had an area under the curve (AUC) of 0.557 (95% confidence interval (CI) from 0.536 to 0.577). The clinically feasible live birth model included age, starting dose, and AMH and had an AUC of 0.554 (95% CI from 0.530 to 0.578). Two models were selected as the optimal model for combined treatment risk, as their performance was equal. One included age, starting dose, AMH, and bFSH; the other also included gonadotropin-releasing hormone (GnRH) analog. The AUCs for both models were 0.769 (95% CI from 0.729 to 0.809). The clinically feasible model for combined treatment risk included age, starting dose, AMH, and GnRH analog, and had an AUC of 0.748 (95% CI from 0.709 to 0.787).The aim of this study was to create a model including patient characteristics whereby gonadotropin starting dose was predictive of both live birth and treatment risks. The model performed poorly on predicting live birth by modifying the FSH starting dose. On the contrary, predicting treatment risks in terms of OHSS occurrence and management by modifying the gonadotropin starting dose was adequate. This dose-selection model, consisting of easily obtainable patient characteristics, aids in the choice of the optimal gonadotropin starting dose for each individual patient to lower treatment risks and potentially reduce treatment costs.© The Author(s) 2024. Published by Oxford University Press on behalf of European Society of Human Reproduction and Embryology.

Ovarian hyperstimulation syndrome is a serious complication associated with assisted reproductive technology. This systematic review aims to identify who is at high risk for developing ovarian hyperstimulation syndrome, along with evidence-based strategies to prevent it and replaces the document of the same name last published in 2016.Copyright © 2023 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Can a simplified ovarian hyperstimulation syndrome (OHSS) risk assessment index be developed and validated with sufficient discrimination of moderate/severe OHSS from those without OHSS?

Ovarian torsion (OT) in IVF is rare, however, the consequences are significant, which include ovariotomy. In the present study, it was aimed for the first time to compare the incidence of OT between hCG triggered cycles with ICSI and fresh transfer and GnRH-agonist triggered cycles with the ICSI-freeze-all and frozen embryo transfer (FET). In total, 15,577 ICSI cycles performed between 2001 and 2016 were categorised into two groups (Group 1, n: 9978): cycles with controlled ovarian stimulation (COS) and hCG-triggered (Group 2, n: 5599) and COS, with GnRH-agonist only triggered and freeze-all. Thirteen patients (0.13%) were diagnosed with OT and corrected by laparoscopy (12) and laparotomy (1) in Group 1. One patient (0.018%) was diagnosed with OT and corrected by laparotomy in Group 2 (Group 1 vs. Group 2, p = .049). The incidence of severe ovarian hyperstimulation syndrome (OHSS) was 2.4% in Group 1 and 0.05% in Group 2 (p < .001). The use of freeze-all with GnRH agonist trigger in ART significantly reduced the incidence of OT and concomitantly OHSS, with no effect on the reproductive outcome. Impact Statement What is already known on this subject? Adnexal ovarian torsion (OT) is a well-known gynaecological event that constitutes a surgical emergency. Assisted reproduction technologies (ART) may result in ovarian conditions that predispose patients to ovarian hyperstimulation syndrome (OHSS) and torsion. What the results of this study add? The combined use of GnRH agonist trigger for final oocyte maturation after OS with freeze-all and frozen embryo transfer (FET) significantly reduces the incidence of OT, as well as OHSS. What the implications are of these findings for clinical practice and/or further research? The treatment strategy of GnRH agonist trigger with freeze-all significantly reduces the risks of adverse complications.

STUDY QUESTION: Are the LH levels at the start of ovarian stimulation predictive of suboptimal oocyte yield from GnRH agonist triggering in GnRH antagonist down-regulated cycles? SUMMARY ANSWER: LH levels at the start of ovarian stimulation are an independent predictor of suboptimal oocyte yield following a GnRH agonist trigger. WHAT IS KNOWN ALREADY: A GnRH agonist ovulation trigger may result in an inadequate oocyte yield in a small subset of patients. This failure can range from empty follicle syndrome to the retrieval of much fewer oocytes than expected. Suboptimal response to a GnRH agonist trigger has been defined as the presence of circulating LH levels < 15 IU/I 12 h after triggering. It has been shown that patients with immeasurable LH levels on trigger day have an up to 25% risk of suboptimal response. STUDY DESIGN, SIZE, DURATION: In this retrospective cohort study, all patients (n = 3334) who received GnRH agonist triggering (using Triptoreline 0.2 mg) for final oocyte maturation undergoing a GnRH antagonist cycle in our centre from 2011 to 2017 were included. The primary outcome of the study was oocyte yield, defined as the ratio between the total number of collected oocytes and the number of follicles with a mean diameter >10 mm prior to GnRH agonist trigger. PARTICIPANTS/MATERIALS, SETTING, METHODS: The endocrine profile of all patients was studied at initiation as well as at the end of ovarian stimulation. In order to evaluate whether LH levels, not only at the end but also at the start, of ovarian stimulation predicted oocyte yield, we performed multivariable regression analysis adjusting for the following confounding factors: female age, body mass index, oral contraceptives before treatment, basal and trigger day estradiol levels, starting FSH levels, use of highly purified human menopausal gonadotrophin and total gonadotropin dose. Suboptimal response to GnRH agonist trigger was defined as < 10th percentile of oocyte yield. MAIN RESULTS AND THE ROLE OF CHANCE: The average age was 31.9 years, and the mean oocyte yield was 89%. The suboptimal response to GnRH agonist trigger cut-off (< 10th percentile) was 45%, which was exhibited by 340 patients. Following confounder adjustment, multivariable regression analysis showed that LH levels at the initiation of ovarian stimulation remained an independent predictor of suboptimal response even in the multivariable model (adjusted OR 0.920, 95% CI 0.871-0.971). Patients with immeasurable LH levels at the start of stimulation (<0.1 1U/1) had a 45.2% risk of suboptimal response, while the risk decreased with increasing basal LH levels; baseline circulating LH <0.5 IU/L, <2 lU/L and <5 IU/L were associated with a 39.1%, 25.2% and 13.6% risk, respectively. LIMITATIONS, REASONS FOR CAUTION: The main limitation of the study is its retrospective design. WIDER IMPLICATIONS OF THE FINDINGS: This is the largest study of GnRH agonist trigger cycles only, since most of the previous research on the predictive value of basal LH levels was performed in dual trigger cycles. LH values should be measured prior to start of ovarian stimulation. In cases where they are immeasurable, suboptimal response to GnRH agonist trigger can be anticipated, and an individualized approach is warranted.

What are the potential risk factors for poor oocyte recuperation rate (ORR) and oocyte immaturity after GnRH agonist (GnRHa) ovulation triggering?

Ovarian hyperstimulation syndrome (OHSS) is a serious iatrogenic complication of ovarian stimulation using fertility medications. OHSS classification presents the different severity categories and grades of OHSS and optimizes management schemes and prognosis. An initial classification system, which grouped OHSS into mild, moderate and severe categories, was based on patients' symptomatology plus manual estimation of ovarian enlargement and urinary excretion of sex steroids. A revised classification system then also incorporated the use of transvaginal sonography for both estimation of ovarian enlargement and detection of even small amounts of ascitic fluid. The detection of ascites establishes the diagnosis of moderate OHSS which may deteriorate to a severe form and is therefore of major importance. Subsequent modifications defined a group of critical or complicated OHSS in which grave complications have already developed. A consensus on the classification of OHSS should be reached by professional societies. As the revised classification system is very valid and widely used, it should form the basis for a modern classification, with the addition of critical or complicated OHSS to the severe category of the syndrome.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 静脉血栓栓塞症（venous thromboembolism，VTE）可分为深静脉血栓形成（deep vein thrombosis，DVT）和肺动脉栓塞（pulmonary embolism，PE）。孕产妇因其特殊的生理状态，在妊娠期及产褥期发生VTE的风险较非妊娠期显著增加［1］。近年来，随着孕产妇高龄、肥胖、妊娠合并症和并发症等风险因素增加，VTE发病率和病死率不断上升［2-4］。浏览更多请关注本刊微信公众号及当期杂志。

Venous thromboembolism (VTE) is a leading cause of maternal death in the United Kingdom. To address this problem guidance from the Royal College of Obstetricians and Gynaecologists (RCOG) has been developed that recommends the assessment of a woman's risk of thrombosis at specific time-points during pregnancy and postnatally at the time of delivery. The RCOG guidelines provide clinicians with a framework to inform decision-making on the use of thromboprophylaxis and are based on the premise that the higher risk a woman has for VTE, the more likely she is to benefit from prophylaxis - determining her level of risk is based on the number and characteristics of the risk factors that she has. This article will address the pathophysiology of VTE in pregnancy, evidence behind the risk factors for VTE and the use of thromboprophylactic agents. Further, it will reflect on the rationale behind the RCOG guidance.Copyright © 2019 Elsevier Inc. All rights reserved.

Venous thromboembolism (VTE) complicates ∼1.2 of every 1000 deliveries. Despite these low absolute risks, pregnancy-associated VTE is a leading cause of maternal morbidity and mortality.

This study aimed to examine trends in low-molecular-weight heparin (LMWH) use for managing pregnancy-associated venous thromboembolism (VTE) and to explore the correlation between pregnancy-related VTE risk factors and LMWH prescription rates.

A review of the clinical presentation of acute and chronic ovarian torsion, treatment recommendations and possible surgical techniques for fertility preservation in young women.Copyright © 2023. Published by Elsevier Inc.

早期识别产后出血以及准确估计出血量，对预防产后出血以及尽早做出决策有很大的帮助，产后出血的早期识别包括：识别产后出血的高危因素和发生产后出血后的早期识别。常见的估计出血量的方法有称重法、容积法、休克指数法等。

Limited information is available regarding the quantity of blood loss associated with uncomplicated transvaginal oocyte retrieval. The aim of the present study was evaluating the quantity of such a loss.One hundred and fifty consecutive women undergoing oocyte retrieval were recruited. They underwent blood test assessment and ultrasonographic transvaginal evaluation at three different times: (1) immediately before initiating oocyte retrieval, (2) 4-6 h later, and (3) 72 h later.At 4-6 h after oocyte retrieval, the red blood cell count and the hemoglobin concentration were significantly reduced, whereas pelvic free fluid had significantly increased. The estimated median (Interquartile range) blood loss was 72 (-8/162) ml. None of the recruited women was found to have a hemoglobin reduction >2 g/day or an increase in the pelvic free fluid >200 ml or a calculated blood loss >500 ml (0.0%, 95% CI: 0.0-2.4%). No significant worsening from baseline was observed at the 72 h evaluation.The quantity of blood loss following oocyte retrieval is clinically unremarkable in the vast majority of women.

We report the complications observed after transvaginal oocyte retrieval guided by ultrasound in 7,098 IVF cycles. The frequency of severe complications in our patients was 0.08%, of which four cases were intraperitoneal bleeding (0.06%) and two were cases of ovarian abscess (0.003%).Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.