The Clinical Application of Growth Hormone and Its Biological and Molecular Mechanisms in Assisted Reproduction

Novel perspectives on growth hormone regulation of ovarian function: mechanisms, formulations, and therapeutic applications

Delayed childbearing has led to a continuous rise in the incidence of infertility because of social development and the evolving roles of women. Assisted reproductive technology (ART) has provided new opportunities for infertility treatment, such as the application of growth hormone (GH). GH regulates ovarian function through multiple pathways, improving follicular development and hormone secretion. However, traditional GH therapy is limited by issues such as low bioavailability and insufficient delivery efficiency. In recent years, drug delivery systems based on novel biomaterials have provided breakthrough solutions for the innovative application of GH in ART. This review summarizes the mechanisms by which GH affects ovarian endocrine function and focuses on the cutting-edge advancements in GH delivery systems with examination of the innovative applications of composite biomaterials in enhancing the therapeutic efficacy of GH. By analyzing the pharmacokinetic properties of novel formulations, the safety and long-term efficacy of their clinical applications can be evaluated. GH delivery systems based on novel biomaterials considerably improve the bioavailability and targeting of GH and could lead to innovative therapeutic strategies for preventing and treating ovarian dysfunction and related diseases. By integrating multidisciplinary research findings, we provide new insights into the field of reproductive medicine that could lead to theoretical and practical importance for promoting the innovative development of ART.

Exploring the potential benefits of growth hormone co-treatment on embryo quality in IVF: a randomized controlled open-label trial

RESEARCH QUESTION

While growth hormone (GH) is hypothesized to potentially enhance embryo quality, results of current basic and clinical researches remain inconclusive. This study assesses the effect of GH supplementation on embryo quality and explores the relationship between baseline insulin-like growth factor-1 (IGF-1) levels and the efficacy of GH supplementation among Chinese patients undergoing in vitro fertilization (IVF).

DESIGN

A randomized controlled Open-label trial was performed with 128 women experiencing poor embryonic development in IVF. Participants were allocated to the GH group (GH + Gonadotropin-Releasing Hormone [GnRH] antagonist protocol) and the Control group (GnRH antagonist protocol). The primary outcome was the number of high-quality embryos on Day 3.

RESULTS

Patients in the GH group required significantly lower total doses of gonadotropin (2213 ± 667 IU vs. 2573 ± 630 IU, p = 0.0058) and shorter duration of controlled ovarian stimulation (10.1 ± 1.60 days vs. 10.6 ± 1.30 days, p = 0.0488). While there was no statistically significant overall increase in the number of high-quality embryos, subgroup analysis indicated that patients with lower baseline IGF-1 levels, especially those below the lowest quartile, might show a higher rate of high-quality embryos with GH supplementation (p = 0.0488). Additionally, the fresh embryo transfer clinical pregnancy rate was numerically higher in the GH supplementation group (46.2%) compared to the control group (38.5%), although not statistically significant.

CONCLUSIONS

This study suggests that GH co-treatment may enhance ovarian responsiveness in IVF patients with poor embryo quality, thereby reducing the dosage and duration of Gonadotropin (Gn) administration. Among individuals with lower IGF-1 levels, adding GH may improve the rate of high-quality embryos, highlighting the potential benefits of personalized treatment strategies in IVF.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT03966339 (Registration time: 2019-05-24).

Growth Hormone Improves Ovarian Follicle Health in Premature Ovarian Failure Mice by Reducing Apoptosis : (GH Improves Ovarian Follicle Health in POF Mice by Reducing Apoptosis)

Premature ovarian failure (POF) is a perplexing condition in women characterized by cessation of oocyte production in the ovaries. Despite numerous proposed causes for the development of POF, the actual cause of the most POF cases remains unknown. Given that POF significantly affects fertility and is a devastating diagnosis for women, there is an urgent need for the development of new therapies aimed at reducing the long-term health consequences associated with POF. To explore the functions and potential mechanisms of growth hormone (GH) in ovarian development, follicle formation, and oocyte production, we created a mouse model of premature ovarian failure (POF) by administering cisplatin via intraperitoneal injection. Subsequently, we investigated the role of GH in attenuating the POF-induced effects. Our findings demonstrate that GH effectively improves the ovarian coefficient, promotes follicular development, and increases the quantity of oocytes. To explore the functions and potential mechanisms of growth hormone (GH) in ovarian development, follicle formation, and oocyte production, we created a mouse model of premature ovarian failure (POF) by administering cisplatin via intraperitoneal injection. Subsequently, we investigated the role of GH in attenuating the POF-induced effects. Our findings demonstrate that GH effectively improves the ovarian coefficient, promotes follicular development, and increases the quantity of oocytes.

The effects of growth hormone on the outcomes of in vitro fertilization and embryo transfer in age-grouped patients with decreased ovarian reserve: a prospective cohort study

Background

Growth hormone (GH) could improve the outcomes of in vitro fertilization and embryo transfer (IVF-ET) in patients with decreased ovarian reserve (DOR), but which age group will benefit the most has remained controversial. This study aims to explore the outcome of IVF-ET among differently aged patients with DOR treated with GH.

Methods

A total of 846 patients with DOR undergoing IVF-ET from May 2018 to June 2023 at the Reproductive Medicine Center of Sichuan Provincial Women's and Children's Hospital were prospectively enrolled. The patients were divided into group A (< 35 year old, n = 399), group B (35 ~ 40 year old, n = 286), and group C (> 40 year old, n = 161). Each group was sub-divided into the GH part and the control part, with the former receiving pretreatment with GH 4 IU/day on day 2 of the previous menstrual cycle before the injection of gonadotrophin (Gn) until the trigger day. The ovarian stimulation protocol was gonadotrophin-releasing hormone antagonist (GnRH-A) or long-acting GnRH agonist protocol. The quality of oocytes and embryos and the outcome of pregnancy were compared.

Results

In group B, the number (1.16 ± 0.12 vs. 0.74 ± 0.09) and rate (34.27% vs. 23.90%) of high-quality cleavage embryos, rate of implantation (32.37% vs. 22.35%), clinical pregnancy (48.98% vs. 33.67%), and live birth (44.90% vs. 29.59%) were significantly higher, whereas the canceled oocyte retrieval rate was significantly lower (1.49% vs. 6.58%) in the GH part than those of the control part (P < 0.05). In group B, the duration and dose of Gn, number of oocyte retrieved, and rates of normal fertilization, cleavage embryo, blastocyst, high-quality blastocyst, and early miscarriage were not significantly different between the GH and control parts (P > 0.05). In groups A and C, no significant difference was detected in the quality of embryos and outcomes of embryo transfer with or without pretreatment (P > 0.05).

Conclusion

GH could improve the quality of embryos and live birth rate for patients with DOR aged 35-40 years old.

Effects of growth hormone therapy on the onset and progression of pubertal development in girls with idiopathic short stature

OBJECTIVE

The aim of this study was to explore the impact of growth hormone (GH) therapy on the onset and progression of puberty in girls with idiopathic short stature.

METHODS

This study included 541 girls aged between 4.5 and 10.6 years who were receiving GH treatment, monitored over a 22-year follow-up period. Of these, 126 girls have been followed up to the onset of menarche. The participants were divided into two groups: a ISS control group (n = 66) and a group receiving daily GH treatment at a dose of 0.15 iu/kg (n = 60). We assessed the pubertal development and GH usage of these girls every three months.

RESULTS

(1) There was no significant difference in the onset of puberty between the growth hormone (GH) treatment group and the control group; however, the average duration of puberty was longer in the treatment group compared to the control group. (2) During puberty, there were no significant differences in height growth between the treated and untreated groups. (3) The duration of GH treatment showed a significant negative correlation with the age at onset of gonadal development and the age at menarche in females within the treatment group.

CONCLUSION

GH treatment does not seem to accelerate the onset of puberty but may extend its duration, without significantly impacting height growth during puberty. Additionally, longer GH treatment duration is linked to earlier gonadal development and menarche in females.

Comparative efficacy of different growth hormone supplementation protocols in improving clinical outcomes in women with poor ovarian response undergoing assisted reproductive therapy: a network meta-analysis

Growth hormone (GH) has a long-standing history of use as an adjunctive therapy in the treatment of poor ovarian response (POR), but the optimal dosage and timing remains unclear. The aim of this study was to evaluate and compare the efficacy of different GH supplementation protocols through a network meta-analysis (NMA) and determine the optimal treatment protocol. This study was reported based on the Preferred Reporting Items for Systematic Reviews for Network Meta-Analysis (PRISMA-NMA) statement. Databases including PubMed, Web of Science, Cochrane Library and Embase were searched until June 2023. A total of 524 records were retrieved in our search, and 23 clinical studies comprising 4889 cycles were involved. Seven different GH protocols were identified. Results showed that compared to the control group, daily administration of 4-8 IU of GH during the follicular phase of the stimulation cycle had the best comprehensive therapeutic effects on improving the number of retrieved oocytes, mature oocytes, endometrial thickness, and reducing gonadotropin requirements in POR patients undergoing assisted reproductive therapy, with a relatively brief treatment duration and a moderate total GH dose. Subgroup analysis demonstrated that this protocol could significantly improve the clinical pregnancy rate of POR patients in the randomized controlled trials (RCT) subgroup and the African subgroup. Therefore, its clinical application is suggested. Besides, the potential advantages of long-term GH supplementation protocol (using GH for at least 2 weeks before oocyte retrieval) has merit for further research. Rigorous and well-designed multi-arm RCTs are needed in the future to confirm the conclusions drawn from this study.

Influence of repeated estrus synchronization treatment on hormone secretion, growth, and development of dairy goats

In large-scale intensive farms, dairy goats often undergo frequent estrus synchronization (ES) treatment, which may result in a decline in reproductive performance; however, the underlying mechanism remains unclear. The present study aimed to investigate the effect of pregnant mare serum gonadotropin (PMSG) and progesterone (P4)-mediated ES treatment on fertility in dairy goats, while also identifying key metabolic and endocrine mechanisms that influence reproductive performance in does subjected to repeated ES treatment. Forty-eight Saanen does were randomly assigned to two groups (24 goats each) that received ES treatments either thrice fortnightly (3-PMSG) or once (1-PMSG) simultaneously with the third ES treatment of the 3-PMSG group during the breeding season. ES treatment was performed via the intravaginal insertion of a controlled internal drug release (CIDR) device impregnated with 300 mg P4, followed by 300 IU PMSG injections 48 h before CIDR withdrawal. Blood was collected to detect the level of hormones and blood biochemical indices. Additionally, estrus rate, fecundity rate, body weight, size, and lactation performance were measured. The results showed that repeated ES treatment markedly decreased the estrus rate and fecundity rate of goats. Among the does in all groups, there was no substantial difference in follicle stimulating hormone, luteinising hormone, gonadotropin-releasing hormone, melatonin, growth hormone, PMSG, total cholesterol, total protein, and glucose levels, as well as the body weight, body size, and lactation performance. Repeated ES treatment elevated estrogen (E2) levels 36, 48, and 72 h post-CIDR removal; increased P4 upon CIDR insertion; and raised PMSG antibody levels 24, 48, and 72 h post-CIDR removal. The results suggest that elevated anti-PMSG levels are the primary reason for the decline in ES efficiency, and that high E2 and P4 levels at some time points also impair reproductive performance. These findings provide novel insights into the metabolic effects of repeated PMSG stimulation in goats, guiding future reproductive hormone use in breeding practices.

Clinical evidence of growth hormone for infertile women with diminished ovarian reserve undergoing IVF: a systematic review and meta-analysis

Objective

To appraise the current randomized clinical trials (RCTs) for evidence of the association of growth hormone (GH) with improved outcomes in infertile women with diminished ovarian reserve (DOR) undergoing in vitro fertilization (IVF).

Methods

Relevant RCTs published in Chinese or English were identified through a comprehensive search of nine databases from the period of database inception to April 20, 2023. We included trials investigating adjuvant GH during ovarian stimulation and reported the subsequent outcomes. The group with adjuvant GH treatment and the group without adjuvant GH treatment were set up as the trial and control groups, respectively. The quality of RCTs was measured according to the Cochrane Collaboration Handbook.

Results

Of the 579 studies initially identified, 10 RCTs comprising 852 infertile women with DOR were included. The GH dose of individual trials ranged between 3 and 5 IU/day. Overall, we judged the trials to be at high risk of bias in the blinding domain. Pooled results showed that GH was associated with an increased clinical pregnancy rate (RR = 1.63, 95%CI [1.31, 2.03], p < 0.0001) and a greater number of oocytes retrieved (MD = 0.91, 95%CI [0.47, 1.35], p < 0.0001). Favorable associations were also observed when ovarian stimulation was combined with GH therapy for improving the optimal embryos rate (RR = 1.84, 95%CI [1.30, 2.59], p = 0.0005) and the number of optimal embryos (MD = 0.28, 95%CI [0.08, 0.48], p = 0.005) along with reducing the cycle cancellation rate (RR = 0.46, 95%CI [0.24, 0.89], p = 0.02). Moreover, GH resulted in an increase in the fertilization rate (RR = 1.33, 95%CI [1.18, 1.50], p < 0.00001) and the embryo implantation rate (RR = 1.56, 95%CI [1.21, 2.01], p = 0.0006). In addition, there was a significant enhancement in estradiol levels (SMD = 1.18, 95%CI [0.46, 1.91], p = 0.001) and endometrial thickness (MD = 0.75, 95%CI [0.41, 1.09], p < 0.0001) on the day of hCG. With regard to the total number of days and total dose of gonadotrophins used, GH treatment was correlated with shorter days (MD = -0.26, 95%CI [-0.46, -0.06], p = 0.01) and lower dose (MD = -460.97, 95%CI [-617.20, -304.73], p < 0.00001) of gonadotrophins applied during ovarian stimulation. Furthermore, GH in conjunction with the GnRH antagonist protocol was more conducive to improving the number of oocytes retrieved when compared with the GnRH agonist protocol (p < 0.0001). Moreover, a notable association was also seen in IVF combined with GH more than or equal to 4.5 IU/day to increase the number of optimal embryos and estradiol levels on the day of hCG (p < 0.05).

Conclusion

For infertile women with DOR undergoing IVF, adjuvant treatment with GH during ovarian stimulation protocols showed better clinical outcomes, shorter days and lower dosages of gonadotrophin required. Furthermore, well-designed RCTs are needed to verify our results in the future.

Systematic review registration

https://www.crd.york.ac.uk PROSPERO (CRD42023421739).

Impact of growth hormone on IVF/ICSI outcomes and endometrial receptivity of patients undergoing GnRH antagonist protocol with fresh embryo transfer: a pilot study

Introduction

Gonadotropin-releasing hormone antagonist (GnRH-ant) protocol is widely used in the world for controlled ovarian hyperstimulation (COH). However, previous studies have shown that pregnancy outcomes of fresh embryo transfer with GnRH-ant protocol are not ideal. Current studies have demonstrated the value of growth hormone (GH) in improving the pregnancy outcome of elderly women and patients with diminished ovarian reserve, but no prospective studies have confirmed the efficacy of GH in fresh embryo transfer with GnRH-ant protocol, and its potential mechanism is still unclear. This study intends to evaluate the impact of GH on IVF/ICSI outcomes and endometrial receptivity of patients undergoing GnRH-ant protocol with fresh embryo transfer, and preliminarily explore the possible mechanism.

Methods

We designed a randomized controlled trial of 120 infertile patients with normal ovarian response (NOR) who will undergo IVF/ICSI from April 2023 to April 2025, at Department of Reproductive Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology. The patients will be divided into the depot gonadotropin-releasing hormone agonist (GnRH-a) protocol group, GnRH-ant protocol control group, and GnRH-ant protocol plus GH intervention group at a ratio of 1:1:1 by block randomization design. Patients will be followed on enrollment day, trigger day, embryo transfer day, 7 days after oocytes pick-up, 15 days after embryo transfer, 28 days after embryo transfer, and 12 weeks of gestation. The primary outcome is the ongoing pregnancy rate. Secondary outcomes include the gonadotropin dosage, duration of COH, endometrial thickness and pattern, luteinizing hormone, estradiol, progesterone level on trigger day, numbers of retrieved oocytes, high-quality embryo rate, biochemical pregnancy rate, clinical pregnancy rate, implantation rate, ectopic pregnancy rate, early miscarriage rate, multiple pregnancy rate and incidence of moderate and severe ovarian hyperstimulation syndrome. The endometrium of certain patients will be collected and tested for endometrial receptivity.

Ethics and dissemination

The study was approved by the Ethics Committee of Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology [approval number: TJ-IRB20230236; approval date: February 10, 2023]. The research results will be presented at scientific/medical conferences and published in academic journals.

Clinical trial registration

Chinese Clinical Trial Registry; identifier: ChiCTR2300069397.

Regulation of ovarian function by growth hormone: Potential intervention of ovarian aging

Growth hormone (GH) is mainly secreted by eosinophils of anterior pituitary gland. GH plays an important role in regulating the growth and development of many tissues and cells, so it is used in the treatment of many diseases. In recent years, the regulation of GH on ovarian function has attracted much attention. GH has been applied in controlled ovarian hyperstimulation, particularly in the patients with advanced age, diminished ovarian reserve (DOR) and poor ovarian response (POR). GH can directly bind to the growth hormone receptor (GHR) on the ovary to promote the growth, maturation and ovulation of follicles, as well as to inhibit follicular atresia. GH so as to promote the occurrence of early follicles, enhance the sensitivity of follicles to gonadotropins, accelerate the maturation of oocyte nucleus, improve mitochondrial activity and the quality of oocytes through the insulin-like growth factor (IGF) system, which is an indirect regulation. The deep-seated effects of GH on human reproduction and ovarian aging need further basic research and clinical practice.