Ovarian hyperstimulation syndrome (OHSS) is a serious complication of assisted reproductive technology (ART). Risk factors for OHSS include female age, polycystic ovarian morphology and high ovarian reserve. The use of a gonadotrophin-releasing hormone (GnRH) agonist trigger in a freeze-all cycle is an effective strategy for reducing the risk of OHSS in suspected high responders. Various GnRH agonist trigger preparations exist but their use is subject to manufacturer availability. The national shortage of Buserelin necessitated a switch to alternative GnRH agonist trigger preparations such as Modified-Release (MR) Triptorelin resulting in a spike in OHSS cases, prompting an urgent review of our local treatment protocols and an immediate switch to Nafarelin (nasal preparation). We performed a retrospective study of freeze-all GnRH antagonist treatment cycles treated with a GnRH agonist (Triptorelin-MR, Nafarelin, and Buserelin) trigger at a London fertility clinic. The high-risk cohort consisted of patients with ≥18 follicles >12mm on ultrasonography. The diagnosis of OHSS was based on the criteria outlined by the Royal College of Obstetricians and Gynaecologists (RCOG). Relevant clinical data were extracted from medical records including female age, antral follicle count (AFC), anti-Mullerian hormone (AMH), ovarian stimulation dose (international units; IU), trigger preparation, oestradiol level on trigger day (pmol/l), oocyte yield, and the diagnosis and management of OHSS. A total of 333 patients underwent a freeze-all GnRH antagonist cycle between January 2023 and September 2024, 224 due to a high-risk of OHSS (≥18 follicles >12mm). The GnRH agonist preparations used included: Triptorelin-MR only (0.75 mg subcutaneous injection, SC; n = 69), Triptorelin-MR (0.375 mg SC) plus Menopur (150 IU SC; n = 49), Buserelin (2 mg SC; n = 69), and Nafarelin (1.6 mg nasal spray; n = 37). Forty-three patients met the RCOG diagnostic criteria for OHSS (mild n = 5, moderate n = 25 and severe n = 13). Six patients required inpatient OHSS management; none required intensive care or a chest/abdominal drain. Of those that developed severe OHSS, 92.3% (n = 12/13) had received Triptorelin-MR only or in combination with Menopur. Based on this cohort, Triptorelin-MR containing triggers are associated with a 12-fold increased risk of severe OHSS compared with other preparations and should not be used as a GnRH agonist trigger in patients at high risk of OHSS.

Gonadotropin-releasing hormone agonists are used to treat central precocious puberty and are increasingly prescribed in gender-affirming care. Despite well-established reproductive effects, their broader physiological effects during puberty remain poorly understood. Male and female Wistar rats received a depot triptorelin injection at pubertal onset. Body mass, food intake, and locomotor activity were monitored. After 28 days, reproductive function was assessed, and pituitary and hypothalamic gene expression was analyzed. Changes in gonadal weight, estrous cycle, folliculogenesis, seminiferous tubules' morphology, and sperm count confirmed the suppression of pubertal maturation. Triptorelin downregulated Gnrhr and Lhb, demonstrating suppression of gonadotrope function. Despite comparable reproductive suppression, metabolic responses to triptorelin were strongly sex-dependent. Females exhibited increased body weight gain accompanied by delayed hyperphagia, whereas males showed reduced body weight gain, unchanged food intake, and increased mean locomotor speed. Female-specific transcriptional remodeling was observed in the hypothalamus, characterized by downregulation of Npy and Lepr and upregulation of Sst and Kiss1 expression. Collectively, these findings demonstrate that pubertal triptorelin treatment induces profound reproductive suppression in both sexes while eliciting sex-specific hypothalamic adaptations in pathways regulating energy homeostasis. This suggests that puberty blockers exert broader neuroendocrine effects beyond the suppression of reproductive maturation.

Prostate cancer (PCa) is the second most common cancer in men. For patients with high-volume metastatic PCa (mPCa) who are fit for docetaxel, a triplet therapy regimen consisting of androgen deprivation therapy (ADT), chemotherapy, and an androgen receptor pathway inhibitor (ARPI) is recommended. Adding local radiotherapy to triplet therapy has been shown to alleviate symptoms and reduce disease progression. However, the benefit of combining triplet therapy with local surgery remains unclear and warrants further investigation in the present study.

Extremely rare cases show co-occurrence of Sjogren-Larsson syndrome (SLS) and central precocious puberty (CPP), and our understanding of it is still limited. In this case report, we reported a 9-year-old boy (weight: 20 kg; height: 120 cm) showing SLS and CPP simultaneously. The patient presented to our hospital with testicle enlargement and presence of pubic hair. SLS was diagnosed based on the presence of ichthyosis and intelligent disability, together with genetic confirmation by next-generation sequencing, which identified two pathogenic variants (c.608_609del and c.1157A>G) in the ALDH3A2 gene. The diagnosis of CPP was established based on mildly advanced bone age, ultrasonographic evidence of pubertal development, and elevated basal gonadotropin and testosterone levels. The patient subsequently received triptorelin acetate (3.75mg) for treating CPP, while merely moisturization and rehabilitation was used for treating SLS. In the follow-up, he showed growth delay, with a body height of 120 cm at age 8.5 years old and 123.5 cm at 9.5 years old.

In captive cranes, chronic reproductive activity, aggression, and feather destructive behaviors are observed, and deslorelin implants have been used at the International Crane Foundation (ICF) to attempt to suppress gonadal hormone production. These sustained-release gonadotropin-releasing hormone agonist implants are generally effective in suppressing gonadal activity in mammals for 12-24 mon. However, in birds, the efficacy is substantially less, with greater variation in response and generally a much shorter duration of effect served. For this retrospective study, the medical record database of ICF was searched for deslorelin use in cranes. Thirteen individuals having received a total of 67 implants were identified for inclusion in this retrospective study. Seven species were represented. Cranes received implants to either stop or slow egg production (n = 56 treatments) or improve behaviors such as aggression and feather destructive behavior (n = 11 treatments). There were varied responses, with some individuals continuing to lay eggs an average of 30 d after treatment and others ceasing to lay eggs for the rest of the year. There were also variations in response between years within the same individuals. Aggression improved following treatment (n = 2 treatments total, n = 2 individuals). There was minimal response in relation to feather destructive behavior (n = 9 treatments total, n = 3 individuals).

Advanced maternal age (AMA) is a major challenge in reproductive medicine, compounded by coexisting conditions such as adenomyosis and endometriosis, which impair oocyte competence and endometrial receptivity. Prolonged gonadotropin-releasing hormone agonist (GnRHa) protocols have been proposed to improve in vitro fertilization-embryo transfer (IVF-ET) outcomes. We report the case of a 41-year-old Indonesian woman with 13 years of primary infertility, AMA, adenomyosis, endometriosis, and male factor infertility. Following laparoscopic excision of endometriosis, she underwent a prolonged GnRH agonist protocol with depot triptorelin, followed by controlled ovarian stimulation using recombinant FSH and LH. Despite an initially modest response, eight oocytes were retrieved and all fertilized via ICSI. Two good-quality day-3 embryos were transferred fresh, and three blastocysts were cryopreserved. Intensive luteal support with hCG, progesterone, dydrogesterone, and estradiol was administered. Serial β-hCG confirmed early pregnancy, and at the time of reporting, she is 35+6 weeks pregnant with a viable singleton and unremarkable antenatal course. This case demonstrates that prolonged GnRHa protocols may offer favorable outcomes in women with AMA and multiple adverse prognostic factors, including adenomyosis, endometriosis, and male factor infertility. While encouraging, such results require cautious interpretation, and further prospective studies incorporating preimplantation genetic testing and cumulative live birth rate are needed to clarify their broader applicability.

This study aimed to conduct computer searches in PubMed, Web of Science, Embase, the Cochrane Library, CNKI, VIP, Wanfang, and CBM databases. Literature was screened and data extracted according to the inclusion and exclusion criteria. RevMan 5.3 was used to assess the methodological quality of the included studies, while Stata 14.0 was employed to rank the efficacy and safety of the five interventions. This analysis included 20 randomised controlled trials involving a total of 2,400 patients. The cumulative probability ranking results showed that, for improving clinical pregnancy rate (CPR), leuprorelin (97.8%) ranked highest, followed by cetrorelix (70.7%), triptorelin (47.9%), buserelin (18.2%), and ganirelix (15.3%). For improving the live birth rate (LBR), leuprorelin (99.9%) ranked highest, followed by triptorelin (44.1%) and cetrorelix (5.9%). For reducing the incidence of ovarian hyperstimulation syndrome (OHSS), cetrorelix (96.9%) ranked highest, followed by buserelin (58.7%), ganirelix (57.5%), leuprorelin (21.2%), and triptorelin (15.7%). Cetrorelix demonstrated superior performance in reducing the risk of OHSS, while leuprorelin was more effective in improving CPR and LBR. For women with polycystic ovary syndrome at high risk of OHSS, cetrorelix is recommended. For patients with the primary goal of improving CPR or LBR, leuprorelin is the more appropriate choice. Key Words: Polycystic ovary syndrome, Infertility, GnRH agonist, GnRH antagonist, Assisted reproduction.

Rabbits are reflex ovulators that require exogenous hormonal stimulation, typically a Gonadotropin-releasing hormone (GnRH) analogue, to induce ovulation during Artificial Insemination (AI). While intramuscular injection is the reference standard, intravaginal administration via semen supplementation offers welfare advantages by reducing handling. However, this route often requires higher doses due to rapid proteolytic degradation. This study evaluated three GnRH analogues (fertirelin, buserelin, and deslorelin) administered intravaginally in New Zealand White rabbits, assessing on ovulation induction, reproductive performance, and the minimum effective concentration. Three experiments were performed, including direct ovulation assessment by laparoscopy and evaluation of delivery rate and prolificacy in lactating and non-lactating does. The semen extender included 20 mM EDTA to enhance hormone stability. Ovulation frequency and delivery rate were significantly affected by the analogue used (p < 0.05). Fertirelin consistently showed the highest efficacy, achieving ovulation and delivery rates equivalent to the intramuscular control, even at a reduced dose of 1 μg. Deslorelin showed intermediate efficacy, whereas intravaginal buserelin yielded the lowest results. Non-lactating does showed higher delivery rates than lactating ones (P < 0.05), however, no significant interaction was detected between analogue type and physiological status, indicating consistent fertirelin efficacy across reproductive conditions. Although no-significant (p = 0.086), a biological trend suggested that the relative advantage of fertirelin may become pronounced under demanding physiological conditions such as lactation. Neither analogue nor physiological status influenced total or live litter size. The stable performance of fertirelin irrespective of physiological condition supports its superior receptor affinity, making it a promising candidate for welfare-oriented intravaginal AI protocols in rabbits.