To the best of our knowledge, this is the first case of pregnancy with a healthy baby after treatment with an oral gonadotropin-releasing hormone (GnRH) antagonist in women with premature ovarian insufficiency. A 36-year-old female presented at our hospital after being diagnosed with premature ovarian insufficiency by a previous doctor. We administered clomiphene, human menopausal gonadotropin (hMG), and GnRH antagonist (injection) together with estrogen replacement for 11 cycles (27 months), but no follicular development was observed. When the oral GnRH antagonist (relugolix), which has recently become available, was used in the 12th cycle, follicular growth of 13 mm was confirmed on the 14th day of stimulation. After stimulation, the use of hMG and GnRH antagonist (injection) was continued, and a maturation trigger, human chorionic gonadotropin 10000 IU, was administered. Oocyte retrieval was performed successfully, intracytoplasmic sperm injection and frozen embryo transfer were performed, and fetal heartbeat was confirmed. The patient was admitted to the perinatal management facility. She delivered a healthy baby of 3,732 g via cesarean section at 41 weeks +2. This case shows the possibility of using an oral GnRH antagonist as an option for infertility treatment.

BACKGROUND: The utilization of a double trigger, involving the co-administration of gonadotropin-releasing hormone agonist (GnRH-a) and human chorionic gonadotropin (hCG) for final oocyte maturation, is emerging as a novel approach in gonadotropin-releasing hormone antagonist (GnRH-ant) protocols during controlled ovarian hyperstimulation (COH). This protocol involves administering GnRH-a and hCG 40 and 34 h prior to ovum pick-up (OPU), respectively. This treatment modality has been implemented in patients with low/poor oocytes yield. This study aimed to determine whether the double trigger could improve the number of top-quality embryos (TQEs) in patients with fewer than three TQEs.
METHODS: The stimulation characteristics of 35 in vitro fertilization (IVF) cycles were analyzed. These cycles were triggered by the combination of hCG and GnRHa (double trigger cycles) and compared to the same patients\' previous IVF attempt, which utilized the hCG trigger (hCG trigger control cycles). The analysis involved cases who were admitted to our reproductive center between January 2018 and December 2022. In the hCG trigger control cycles, all 35 patients had fewer than three TQEs.
RESULTS: Patients who received the double trigger cycles yielded a significantly higher number of 2PN cleavage embryos (3.54 ± 3.37 vs. 2.11 ± 2.15, P = 0.025), TQEs ( 2.23 ± 2.05 vs. 0.89 ± 0.99, P < 0.001), and a simultaneously higher proportion of the number of cleavage stage embryos (53.87% ± 31.38% vs. 39.80% ± 29.60%, P = 0.043), 2PN cleavage stage embryos (43.89% ± 33.01% vs. 27.22% ± 27.13%, P = 0.014), and TQEs (27.05% ± 26.26% vs. 14.19% ± 19.76%, P = 0.019) to the number of oocytes retrieved compared with the hCG trigger control cycles, respectively. The double trigger cycles achieved higher rates of cumulative clinical pregnancy (20.00% vs. 2.86%, P = 0.031), cumulative persistent pregnancy (14.29% vs. 0%, P < 0.001), and cumulative live birth (14.29% vs. 0%, P < 0.001) per stimulation cycle compared with the hCG trigger control cycles.
CONCLUSIONS: Co-administration of GnRH-agonist and hCG for final oocyte maturation, 40 and 34 h prior to OPU, respectively (double trigger) may be suggested as a valuable new regimen for treating patients with low TQE yield in previous hCG trigger IVF/intracytoplasmic sperm injection (ICSI) cycles.

UNASSIGNED: This study aims to determine whether the live birth rates were similar between GnRH antagonist original reference product Cetrotide® and generic Ferpront®, in gonadotropin-releasing hormone (GnRH) antagonist protocol for controlled ovarian stimulation (COS).
UNASSIGNED: This retrospective cohort study investigates COS cycles utilizing GnRH antagonist protocols. The research was conducted at a specialized reproductive medicine center within a tertiary care hospital, spanning the period from October 2019 to October 2021. Within this timeframe, a total of 924 cycles were administered utilizing the GnRH antagonist originator, Cetrotide® (Group A), whereas 1984 cycles were undertaken using the generic, Ferpront® (Group B).
UNASSIGNED: Ovarian reserve markers, including anti-Mullerian hormone, antral follicle number, and basal follicular stimulating hormone, were lower in Group A compared to Group B. Propensity score matching (PSM) was performed to balance these markers between the groups. After PSM, baseline clinical features were similar, except for a slightly longer infertile duration in Group A versus Group B (4.43 ± 2.92 years vs. 4.14 ± 2.84 years, P = 0.029). The duration of GnRH antagonist usage was slightly longer in Group B than in Group A (6.02 ± 1.41 vs. 5.71 ± 1.48 days, P < 0.001). Group B had a slightly lower number of retrieved oocytes compared to Group A (14.17 ± 7.30 vs. 14.96 ± 7.75, P = 0.024). However, comparable numbers of usable embryos on day 3 and good-quality embryos were found between the groups. Reproductive outcomes, including biochemical pregnancy loss, clinical pregnancy, miscarriage, and live birth rate, did not differ significantly between the groups. Multivariate logistic regression analyses suggested that the type of GnRH antagonist did not independently impact the number of oocytes retrieved, usable embryos, good-quality embryos, moderate to severe OHSS rate, clinical pregnancy, miscarriage, or live birth rate.
UNASSIGNED: The retrospective analysis revealed no clinically significant differences in reproductive outcomes between Cetrotide® and Ferpront® when used in women undergoing their first and second COS cycles utilizing the GnRH antagonist protocol.

UNASSIGNED: The main purpose of this study is to compare the embryo development and clinical outcomes of women in different age groups undergoing in vitro fertilization (IVF) processes using gonadotrophin-releasing hormone (GnRH) antagonist protocol, GnRH agonist long protocol, and early follicular phase protocol. We aim to provide reliable reference for future clinical treatments.
UNASSIGNED: We conducted a detailed analysis of patients who underwent treatment between January 2021 and February 2023. 1) In the overall patient population, we comprehensively compared the basic characteristics, the embryo development, and the clinical outcomes of patients treated with three different ovarian stimulation protocols, including the GnRH antagonist protocol group (n=4173), the agonist long protocol group (n=2410), and the early follicular phase long protocol group (n=341). 2) We divided the overall population into three age groups, one group for patients under 30 years old (n=2576), one for patients aged 30-35 (n=3249), and one for patients older than 35 years old (n=1099). Then, we compared the three stimulation protocols based on the group division. We separately compared the embryo development and clinical outcomes of patients using the three stimulation protocols in the under 30 years old, the 30-35 years old, and the over 35 years old age groups. With this analysis, we aimed to explore the response of different age groups to different stimulation protocols and their impact on the success rate of IVF.
UNASSIGNED: 1) In the overall population, we found that the average number of oocytes retrieved in the GnRH agonist long protocol group was significantly higher than that in the GnRH antagonist protocol group ([13.85±7.162] vs. [13.36±7.862], P=0.0224), as well as the early follicular phase long protocol group ([13.85±7.162] vs. [11.86±6.802], P<0.0001). Patients in the GnRH antagonist protocol group not only had a significantly lower starting dose of gonadotrophin (Gn) compared to the other two groups (P<0.05) but also had a significantly lower number of days of Gn use (P<0.05). The blastocyst formation rate in the GnRH antagonist protocol group was the highest among the three groups, significantly higher compared to the GnRH agonist long protocol group (64.91% vs. 62.35%, P<0.0001) and the early follicular phase long protocol group (64.91% vs. 61.18%, P=0.0001). However, there were no significant differences in the clinical pregnancy rates or the live birth rates among the three groups treated with different ovarian stimulation protocols (P>0.05). 2) In the <30 age group, the blastocyst formation rate in the GnRH antagonist protocol group was the highest among the three groups, significantly higher compared to the GnRH agonist long protocol group (66.12% vs. 63.33%, P<0.0001) and the early follicular phase long protocol group (66.12% vs. 62.13%, P=0.0094). In the 30-35 age group, the blastocyst formation rate in the GnRH antagonist protocol group was the highest among the three groups, significantly higher compared to the GnRH agonist long protocol group (64.88% vs. 62.93%, P=0.000 9) and the early follicular phase long protocol group (64.88% vs. 60.39%, P=0.0011). In the >35 age group, the blastocyst formation rate in the GnRH antagonist protocol group was significantly higher than that in the GnRH agonist long protocol group (59.83% vs. 56.51%, P=0.0093), while there was no significant difference compared to that of the early follicular phase long protocol group (P>0.05). In the three age groups, we found that there were no significant differences in clinical pregnancy rate, live birth rate, and neonatal outcome indicators (fetal weight and Apgar score) among the three stimulation protocols (antagonist protocol, GnRH agonist long protocol, and early follicular phase long protocol) (P>0.05). The findings showed no significant differences between clinical and neonatal outcomes in patients of all ages, regardless of the ovarian stimulation protocol, suggesting that the three ovarian stimulation protocols have similar therapeutic effects in patients of different ages. The results of this study have important implications for the selection of an appropriate ovarian stimulation protocol and the prediction of treatment outcomes.
UNASSIGNED: In the younger than 30 and 30-35 age groups, the GnRH antagonist protocol showed a more significant advantage over the GnRH agonist long protocol and the early follicular phase long protocol. This suggests that for younger and middle-aged patients, the antagonist protocol may lead to better outcomes during ovarian stimulation. In the older than 35 age group, while the antagonist protocol still outperformed the GnRH agonist long protocol, there was no significant difference compared to the early follicular phase long protocol. This may imply that with increasing age, the early follicular phase long protocol may have effects similar to the antagonist protocol to some extent. The advantages of the antagonist protocol lie in its ability to reduce stimulation duration and the dosage of GnRH, while enhancing patient compliance with treatment. This means that patients may find it easier to accept and adhere to this treatment protocol, thereby improving treatment success rates. Particularly for older patients, the use of the antagonist protocol may significantly increase the blastocyst formation rate, which is crucial for improving the success rates. Although there were no significant differences in the clinical outcomes of patients treated with the three protocols in each age group, further research is still needed to validate these findings. Future multicenter studies and increased sample sizes may help comprehensively assess the efficacy of different stimulation protocols. Additionally, prospective studies are needed to further validate these findings and determine the optimal treatment strategies.

Background: Normal reproductive function requires adequate regulation of follicle stimulating hormone (FSH) and luteinizing hormone (LH) secretion. During ovarian stimulation for in-vitro fertilization (IVF), some patients will demonstrate an early rise in LH despite being treated with a gonadotropin releasing-hormone (GnRH) antagonist, sometimes necessitating cycle cancellation. Previous studies have demonstrated a possible link between a premature LH rise with ovarian response to gonadotropins. We sought to determine what clinical parameters can predict this premature LH rise and their relative contribution. Methods: A retrospective study of 382 patients who underwent IVF treatment at Rambam Medical Center. The patients were stratified into age groups. A model predicting premature LH rise based on clinical and demographic parameters was developed using both multiple linear regression and a machine-learning-based algorithm. Results: LH rise was defined as the difference between pre-trigger and basal LH levels. The clinical parameters that significantly predicted an LH rise were patient age, BMI, LH levels at stimulation outset, LH levels on day of antagonist administration, and total number of stimulation days. Importantly, when analyzing the data of specific age groups, the model\'s prediction was strongest in young patients (age 25-30 years, R2 = 0.88, p < .001) and weakest in older patients (age > 41 years, R2 = 0.23, p = .003). Conclusions: Using both multiple linear regression and a machine-learning-based algorithm of patient data from IVF cycles, we were able to predict patients at risk for premature LH rise and/or LH surge. Utilizing this model may help prevent IVF cycle cancellation and better timing of ovulation triggering.

UNASSIGNED: To investigate the effect of body mass index (BMI) on progesterone (P) level on trigger day in gonadotropin-releasing hormone antagonist (GnRH-ant) cycles.
UNASSIGNED: This study was a retrospective cohort study. From October 2017 to April 2022, 412 in-vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) patients who were treated with GnRH-ant protocol for controlled ovarian hyperstimulation (COH) in the reproductive center of our hospital were selected as the research objects. Patients were divided into three groups according to BMI level: normal weight group (n = 230):18.5 kg/m2≤BMI < 24 kg/m2; overweight group (n = 122): 24 kg/m2≤BMI < 28 kg/m2; Obesity group (n = 60): BMI ≥ 28 kg/m2. Variables with p < .10 in univariate analysis (BMI, basal FSH, basal P, FSH days, Gn starting dose and E2 level on trigger day) and variables that may affect P level on trigger day (infertility factors, basal LH, total FSH, HMG days and total HMG) were included in the multivariate logistic regression model to analyze the effect of BMI on P level on trigger day of GnRH-ant protocol.
UNASSIGNED: After adjustment for confounding factors, compared with that in normal weight patients, the risk of serum P elevation on trigger day was significantly lower in overweight and obese patients (OR = 0.434 and 0.199, respectively, p < .05).
UNASSIGNED: The risk of P elevation on trigger day in GnRH-ant cycles decreased with the increase of BMI, and BMI could be used as one of the predictors of P level on trigger day in GnRH-ant cycles.

In vertebrates, folliculogenesis and ovulation are regulated by two distinct pituitary gonadotropins: follicle-stimulating hormone (FSH) and luteinizing hormone (LH). Currently, there is an intriguing consensus that a single hypothalamic neurohormone, gonadotropin-releasing hormone (GnRH), regulates the secretion of both FSH and LH, although the required timing and functions of FSH and LH are different. However, recent studies in many non-mammalian vertebrates indicated that GnRH is dispensable for FSH function. Here, by using medaka as a model teleost, we successfully identify cholecystokinin as the other gonadotropin regulator, FSH-releasing hormone (FSH-RH). Our histological and in vitro analyses demonstrate that hypothalamic cholecystokinin-expressing neurons directly affect FSH cells through the cholecystokinin receptor, Cck2rb, thereby increasing the expression and release of FSH. Remarkably, the knockout of this pathway minimizes FSH expression and results in a failure of folliculogenesis. Here, we propose the existence of the \"dual GnRH model\" in vertebrates that utilize both FSH-RH and LH-RH.

OBJECTIVE: When hormone therapy (HT) is combined with radiotherapy, understanding the recovery of testosterone levels after the end of HT becomes crucial for considering subsequent therapy. The aim of this study was to determine the factors influencing the time to recovery of testosterone levels after discontinuation of HT and the likelihood of recovery.
METHODS: The study included a total of 108 patients with prostate cancer who were treated with GnRH agonist in combination with radiotherapy and followed up for at least 12 months after discontinuation of the GnRH agonist. The presence of recovery of testosterone levels and the time to recovery were investigated. Univariate and multivariate analyses were performed on several factors contributing to testosterone recovery, including age at initiation of HT, and the duration of HT.
RESULTS: Testosterone levels recovered in 61 cases (56.5%). The median time to recovery was 14.8 months. There was a significant difference in the recovery of testosterone levels between patients aged ≥71 years and those aged <71 years at the start of HT (p=0.002), and between those who had been on HT for ≥34 months and those for <34 months (p=0.031). In both univariate and multivariate analyses, age at initiation of HT and duration of HT contributed to the recovery of testosterone levels.
CONCLUSIONS: The rate of recovery of testosterone levels after long-term (median 34.3 months) HT was lower in patients who were older than 71 years at the start of HT.

The physiology of reproduction has been of interest to researchers for centuries. The purpose of this work is to review the development of our knowledge on the neuroendocrine background of the regulation of ovulation. We first describe the development of the pituitary gland, the structure of the median eminence (ME), the connection between the hypothalamus and the pituitary gland, the ovarian and pituitary hormones involved in ovulation, and the pituitary cell composition. We recall the pioneer physiological and morphological investigations that drove development forward. The description of the supraoptic-paraventricular magnocellular and tuberoinfundibular parvocellular systems and recognizing the role of the hypophysiotropic area were major milestones in understanding the anatomical and physiological basis of reproduction. The discovery of releasing and inhibiting hormones, the significance of pulse and surge generators, the pulsatile secretion of the gonadotropin-releasing hormone (GnRH), and the subsequent pulsatility of luteinizing (LH) and follicle-stimulating hormones (FSH) in the human reproductive physiology were truly transformative. The roles of three critical neuropeptides, kisspeptin (KP), neurokinin B (NKB), and dynorphin (Dy), were also identified. This review also touches on the endocrine background of human infertility and assisted fertilization.

OBJECTIVE: The present study was performed to characterize and compare the perfusion of vaginal and uterine arteries after challenging the reproductive tract of dairy cows via natural mating, artificial insemination (AI), or intravaginal deposition (vaginal fundus) of different biological fluids or a placebo.
METHODS: In a double-blind study, six German Holstein cows were administered PGF2α during dioestrus and 48 h later treated with GnRH. Intravaginal or intrauterine treatments were carried out 12 h after GnRH was administered. Animals served as their controls, using a cross-over design with an interval of 14 days between experiments. The experimental animals were allocated to receive the following treatments: natural mating (N), intrauterine artificial insemination (A), intravaginal deposition (vaginal fundus) of 6 mL raw semen (R) or 6 mL seminal plasma (S), and compared to their controls [control 1: 6 mL placebo (P: physiological saline); control 2: no treatment (C)). Corresponding time intervals were chosen for the untreated control oestrus. Blood flow volume (BFV) in the uterine (u) and vaginal (v) arteries ipsilateral to the ovary bearing the preovulatory follicle was determined using transrectal Doppler sonography.
RESULTS: All animals exhibited oestrus and ovulated between 30 and 36 h after GnRH. Transient increases (P < 0.05) in vaginal blood flow occurred between 3 and 12 h following mating as well as 3 to 9 h after deposition of raw semen and seminal plasma, respectively. The most distinct increases (199%) in vBFV occurred 6 h after mating compared to values immediately before mating (= time 0 h). Neither AI nor deposition of a placebo into the vagina affected vBFV (P > 0.05). Only mating and deposition of either raw semen, seminal plasma or AI increased uBFV (P < 0.003). The greatest rise in uBFV occurred after natural mating. Maximum uBFV values were detected 9 h after mating when values were 79% greater (P < 0.05) than at 0 h.
CONCLUSIONS: The natural mating, deposition of raw semen or seminal plasma and conventional AI affect vaginal and/or uterine blood flow to different degrees. The factors responsible for these alterations in blood flow and their effects on fertility remain to be clarified in future studies.