Effects of growth hormone on in vitro maturation of germinal vesicle of human oocytes retrieved from small antral follicles

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

Growth hormone (GH) has been used as a co-gonadotrophin in assisted reproduction, particularly in poor ovarian responders. The application of GH has been alleged to activate primordial follicles and improve oocyte quality, embryo quality, and steroidogenesis. However, the effects of GH on the live birth rate among women is controversial. Additionally, although the basic biological mechanisms that lead to the above clinical differences have been investigated, they are not yet well understood. The actions of GH are mediated by GH receptors (GHRs) or insulin-like growth factors (IGFs). GH regulates the vital signal transduction pathways that are involved in primordial follicular activation, steroidogenesis, and oocyte maturation. However, the therapeutic windows and duration of GH administration during assisted reproductive technology require further investigation. The review aimed to clarify the role of GH in human fertility from a molecular and biological point of view to provide evidence for proper GH administration.

Rescue IVM of Denuded GV- and MI-Stage Oocytes of Premenopausal Rats with Oncostatin M, Insulin-like Growth Factor I, and Growth Hormone

Immature oocytes are retrieved and matured through in vitro maturation (IVM). Maturation, fertilization rates, and embryo development via IVM are all lower than those found in vitro fertilization (IVF) cycles. We investigated the effects of oncostatin M (OSM), insulin-like growth factor-1 (IGF-I), and growth hormone (GH) in rescue IVM. A total of 111 germinal vesicle (GV) and 17 metaphase I (MI) oocytes were obtained after conventional IVF from 28 female Wistar albino rats. Denuded immature oocytes were cultured in maturation medium supplemented with OSM, IGF-1, or GH. The quantities of metaphase II (MII) oocytes matured from the GV stage were 17 of 30 (56.6%), 15 of 28 (53.5%), 10 of 30 (33.3%), and 7 of 23 (30.3%), in control, OSM, IGF-I, and GH groups, respectively. Maturation rates in control and OSM groups were higher than those in IGF-I and GH groups (p = 0.001). The quantities of MII oocytes matured from MI stage were 7 of 7 (100%), 4 of 4 (100%), 1 of 1 (100%), and 1 of 5 (20%) in control, OSM, IGF-I, and GH groups, respectively. Maturation rates from MI to MII stages in control, OSM, and IGF-I groups were higher than those in the GH group (p = 0.004). Acceptable maturation rates are observed with OSM in rat oocytes in rescue IVM.

The role of growth hormone for fertility in women with hypopituitarism

Growth hormone (GH) is an important regulator of the female reproductive system. In vitro and non-human in vivo studies demonstrate a role of GH in steroidogenesis, folliculogenesis, and post-fertilization development. Given its ability to modulate the reproductive system and potentiate the effects of gonadotropins, a beneficial role of GH replacement therapy to optimize fertility has been suggested. Women with hypopituitarism have lower pregnancy and live birth rates. Limited data suggest a role of GH in enhancing fertility management in women with hypopituitarism. GH replacement therapy may be especially relevant in women with hypopituitarism as well as in women considered poor ovarian responders and require assisted reproductive techniques.

Importance of IGF-I levels in IVF: potential relevance for growth hormone (GH) supplementation

Purpose

Growth hormone (GH) supplementation in association with in vitro fertilization (IVF) is worldwide again increasing, even though study outcomes have been discrepant. Since GH acts via insulin-like growth factor-1 (IGF-1), its utilization in IVF would only seem to make sense with low IGF-1. We, therefore, determined whether IGF-I levels affect IVF outcomes.

Methods

Retrospectively, 302 consecutive first fresh, non-donor IVF cycles were studied, excluding patients on GH supplementation. Patients were divided into 3 subgroups: IGF-1 in lower 25th percentile (group A, < 132 ng/mL, n = 64); 25th–75th percentile (B, 133–202 ng/mL, n = 164), and upper 25th percentile (C, > 202 ng/mL, n = 74). IGF-1 was tested immunochemiluminometric with normal range at 78–270 ng/mL. Because of the study patients’ adverse selection and low pregnancy chances, the main outcome measure for the study was cycle cancellation. Secondary outcomes were oocyte numbers, embryos transferred, pregnancies, and live births.

Results

Group A was significantly older than B and C (P = 0.019). IGF-1 decreased with increasing age per year by 2.2 ± 0.65 ng/mL (P = 0.0007). FSH was best in group B and worst in A (trend, P = 0.085); AMH was best in B and worst in A (N.S.). Cycle cancellations were lowest in C (11.6%) and highest in A (25.0%; P = 0.042). This significance further improved with age adjustment (P = 0.021). Oocytes, embryo numbers, pregnancies, and live birth rates did not differ, though oocyte numbers trended highest in B.

Conclusions

Here presented results support the hypothesis that IGF-1 levels affect IVF outcomes. GH treatments, therefore, may be effective only with low IGF-1.

Growth hormone for in vitro fertilisation (IVF)

BACKGROUND

In an effort to improve outcomes of in vitro fertilisation (IVF) cycles, the use of growth hormone (GH) has been considered as adjuvant treatment in ovarian stimulation. Improving the outcomes of IVF is especially important for women with infertility who are considered 'poor responders'. We have compared the outcomes of IVF with adjuvant GH versus no adjuvant treatment in routine use, and specifically in poor responders.

OBJECTIVES

To assess the effectiveness and safety of growth hormone as an adjunct to IVF compared to standard IVF for women with infertility SEARCH METHODS: We searched the following databases (to November 2020): Cochrane Gynaecology and Fertility (CGF) Group specialised register, CENTRAL, MEDLINE, Embase, CINAHL, Epistemonikos database and trial registers together with reference checking and contact with study authors and experts in the field to identify additional trials.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) of adjuvant GH treatment in IVF compared with no adjuvant treatment for women with infertility. We excluded trials where additional adjuvant treatments were used with GH. We also excluded trials comparing different IVF protocols.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures recommended by Cochrane. Two review authors independently performed assessment of trial risk of bias and extraction of relevant data. The primary review outcome was live birth rate. The secondary outcomes were clinical pregnancy rate, oocytes retrieved, embryo transfer, units of gonadotropin used and adverse events, i.e. ectopic pregnancy, multiple pregnancy, ovarian hyperstimulation syndrome (OHSS), congenital anomalies, oedema.

MAIN RESULTS

We included 16 RCTs (1352 women). Two RCTs (80 women) studied GH in routine use, and 14 RCTs (1272 women) studied GH in poor responders. The evidence was low to very low certainty, the main limitations being risk of bias, imprecision and heterogeneity. Adjuvant growth hormone compared to no adjuvant: routine use for in vitro fertilisation (IVF) The evidence is very uncertain about the effect of GH on live birth rate per woman randomised for routine use in IVF (odds ratio (OR) 1.32, 95% confidence interval (CI) 0.40 to 4.43; I² = 0%; 2 trials, 80 participants; very low-certainty evidence). If the chance of live birth without adjuvant GH is assumed to be 15%, the chance of live birth with GH would be between 6% and 43%. There was insufficient evidence to reach a conclusion regarding clinical pregnancy rates per woman randomised, number of women with at least one oocyte retrieved per woman randomised and embryo transfer achieved per woman randomised; reported data were unsuitable for analysis. The evidence is very uncertain about the effect of GH on mean number of oocytes retrieved in normal responders (mean difference (MD) -0.02, 95% CI -0.79 to 0.74; I² = 0%; 2 trials, 80 participants; very low-certainty evidence). The evidence is very uncertain about the effect of GH on mean units of gonadotropin used in normal responders (MD 13.57, 95% CI -112.88 to 140.01; I² = 0%; 2 trials, 80 participants; very low-certainty evidence). We are uncertain of the effect of GH on adverse events in normal responders. Adjuvant growth hormone compared to no adjuvant: use in poor responders for in vitro fertilisation (IVF) The evidence is very uncertain about the effect of GH on live birth rate per woman randomised for poor responders (OR 1.77, 95% CI 1.17 to 2.70; I² = 0%; 8 trials, 737 participants; very low-certainty evidence). If the chance of live birth without adjuvant GH is assumed to be 11%, the chance of live birth with GH would be between 13% and 25%. Adjuvant GH results in a slight increase in pregnancy rates in poor responders (OR 1.85, 95% CI 1.35 to 2.53; I² = 15%; 11 trials, 1033 participants; low-certainty evidence). The results suggest, if the pregnancy rate without adjuvant GH is assumed to be 15%, with GH the pregnancy rate in poor responders would be between 19% and 31%. The evidence suggests that GH results in little to no difference in number of women with at least one oocyte retrieved (OR 5.67, 95% CI 1.54 to 20.83; I² = 0%; 2 trials, 148 participants; low-certainty evidence). If the chance of retrieving at least one oocyte in poor responders was 81%, with GH the chance is between 87% and 99%. There is a slight increase in mean number of oocytes retrieved with the use of GH for poor responders (MD 1.40, 95% CI 1.16 to 1.64; I² = 87%; 12 trials, 1153 participants; low-certainty evidence). The evidence is very uncertain about the effect of GH on embryo transfer achieved (OR 2.32, 95% CI 1.08 to 4.96; I² = 25%; 4 trials, 214 participants; very low-certainty evidence). If the chance of achieving embryo transfer is assumed to be 77%, the chance with GH will be 78% to 94%. Use of GH results in reduction of mean units of gonadotropins used for stimulation in poor responders (MD -1088.19, 95% CI -1203.20 to -973.18; I² = 91%; 8 trials, 685 participants; low-certainty evidence). High heterogeneity in the analyses for mean number of oocytes retrieved and units of GH used suggests quite different effects according to differences including in trial protocols (populations, GH dose and schedule), so these results should be interpreted with caution. We are uncertain of the effect of GH on adverse events in poor responders as six of the 14 included trials failed to report this outcome.

AUTHORS' CONCLUSIONS

The use of adjuvant GH in IVF treatment protocols has uncertain effect on live birth rates and mean number of oocytes retrieved in normal responders. However, it slightly increases the number of oocytes retrieved and pregnancy rates in poor responders, while there is an uncertain effect on live birth rates in this group. The results however, need to be interpreted with caution, as the included trials were small and few in number, with significant bias and imprecision. Also, the dose and regimen of GH used in trials was variable. Therefore, further research is necessary to fully define the role of GH as adjuvant therapy in IVF.

WITHDRAWN: Growth hormone improves insulin-like growth factor 1 and steroid hormone levels in follicle fluid, expression of hormone receptors in granulosa cells, and in vitro fertilization outcomes of poor ovarian responders

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Evaluation of growth hormone co-treatment in in vitro fertilization in patients responding better to the GnRH antagonist short protocol

Objective

The present study aims at evaluating the results obtained after in vitro fertilization in bad responders, using controlled ovarian hyperstimulation together with the use of gonadotrophin releasing hormone (GnRH) antagonist (cetrorelix acetate) in a short protocol.

Methods

This is an analytical, longitudinal, retrospective and controlled study involving patients who underwent in vitro fertilization (IVF) procedures in the assisted reproduction program of the Reproferty clinic, in the municipality of São José dos Campos/SP, from January 2012 to December 2016. We collected the data obtained from the medical records of patients considered to have undergone controlled ovarian hyperstimulation using GnRH antagonist (cetrorelix acetate) and Growth Hormone (GH) in a short cycle protocol. The patients considered controls were those submitted to the same hyperstimulation process, without using GH.

Results

There were significant differences in the following analyzed parameters: gonadotrophin regimen dose, stimulation duration, and estradiol levels on the day of HCG administration, number of follicles, number of retrieved oocytes, number of mature oocytes and number of good-quality embryos. On the other hand, the GH administration was not significant in the number of cycles that achieved transfer, the number of embryos transferred and the number of frozen cycles. In the case group, there was no increase in the number of cycles that reached pregnancy rate βhCG+; however, the clinical pregnancy rates and live birth rates were significant.

Conclusion

The present investigation demonstrated that GH administration as a supplement in poor responders improves the majority of the parameters to achieve a full term pregnancy in these patients.

Application of Growth Hormone in in vitro Fertilization

Growth hormone (GH) is a peptide hormone secreted mainly by the anterior part of the pituitary gland and plays a critical role in cell growth, development, and metabolism throughout the body. GH can not only directly influence human oocytes and cumulus cells but also indirectly improve oocyte quality through activating synthesis of insulin-like growth factor-I or promoting follicle-stimulating hormone-induced ovarian steroidogenesis. Since GH can regulate female and male infertility, it has been applied in the management of infertility for many years, especially in patients with poor ovarian response or poor prognosis. During ovarian stimulation, GH administration might improve the success rate of in vitro fertilization (IVF) probably through the beneficial effects of GH on oocyte quality as indicated by a higher number of mature oocytes and embryos arriving at the transfer stage and a higher fertility rate in GH-treated patients. However, there is still great controversy in the application of GH in IVF. While some researchers showed that pregnancy, implantation and live birth rates could be increased by ovarian pretreatment with GH, others did not support GH as an effective adjuvant for infertility treatment because the live birth rate was not increased. This study reviewed and summarized recent advancements and benefits in clinical application of GH, trying to reach a just unbiased conclusion regarding the effect of GH therapy in IVF.

Growth Hormone Promotes in vitro Maturation of Human Oocytes

Increasing the success rate of in vitro maturation (IVM) for human oocytes has a major clinical significance. Previous studies have shown that growth hormone (GH) added into IVM medium could promote IVM of oocytes from non-human beings. However, few studies on systematic IVM for human oocytes with GH have been reported. Human germinal vesicle (GV) oocytes collected for IVM were cultured with different concentrations of GH to optimize the concentration. Metaphase II (MII) stage oocytes obtained from IVM were fertilized by intracytoplasmic sperm injection (ICSI). Maturation rate, fertilization rate, and blastocyst rate were assessed after IVM with or without GH. Furthermore, gene expression profiles were compared in oocytes between the two groups using single-cell RNA-seq. The optimal concentration of GH for IVM was 200 ng/ml, and the maturation rate of this group reached 70% which was double that of the control group (35%, P = 0.004). The fertilization rate (73.1 vs. 60.3%) and blastocyst rate (25.0 vs. 15.5%) both had an increasing trend in the GH group compared to controls. Single-cell RNA-Seq and real-time PCR data showed that GH could significantly enhance the expression of genes associated with meiotic progression and embryo development, such as AURKA (aurora kinase A, P = 0.007), PDIA6 (protein disulfide isomerase family A member 6, P = 0.007), LINGO2 (leucine rich repeat and Ig domain containing 2, P = 0.007), and CENPJ (centromere protein J, P = 0.039). Taken together, GH could promote maturation of human oocytes, probably through accelerating meiotic progression, balancing redox homeostasis of cellular environment, and promoting oocyte developmental competence.

Six-week pretreatment with growth hormone improves clinical outcomes of poor ovarian responders undergoing in vitro fertilization treatment: A self-controlled clinical study

AIM

The purpose was to explore whether the 6 weeks of growth hormone (GH) pretreatment could increase the live birth rate of poor ovarian responders (POR).

METHODS

This self-controlled, retrospective study was performed among 380 POR who had GH adjuvant (GH+) at a university-affiliated hospital in Guangzhou, China, from October 2010 to April 2016. Growth hormone was injected daily beginning with the previous menstruation and maintained until ovum pickup, for approximately 6 weeks. Clinical variables between the GH+ cycle and the other GH-free (GH-) cycle of each patient were compared. Both cycles were conducted with a similar conventional control ovarian hyperstimulation protocol for in vitro fertilization treatment. One to one case-control matching was performed to adjust essential confounding factors between GH+ cycles and GH- cycles.

RESULTS

GH pretreatment improved embryo quality (1.14 ± 1.50 vs 0.11 ± 0.48, P < 0.05) and decreased miscarriage (18.8% vs 80.0%, P < 0.05) significantly, resulting in an increase in the live birth rate (23.5% vs 3.9%, P < 0.05). The oocyte utilization rate in GH+ cycles was remarkably improved, even with older patients and more failed previous attempts. Significant improvement in embryo quality was shown by an increased number of good-quality embryos and improved oocyte utilization rate after matching.

CONCLUSIONS

The longer term use of low-dose GH administration for 6 weeks could be beneficial for the utilization of oocytes and for finally increasing the live birth rates of POR.

Effects of growth hormone plus gonadotropins on controlled ovarian stimulation in infertile women of advanced age, poor responders, and previous in vitro fertilization failure patients

OBJECTIVE

To investigate the effects of growth hormone (GH) cotreatment in ovarian stimulation in infertile women of advanced age, poor responders, and patients with one or more previous IVF treatment failures.

MATERIALS AND METHODS

We conducted a retrospective observational study of 436 patients undergoing GH cotreatment in ovarian stimulation. The first arm included 134 infertile women of advanced age. The second arm included 236 patients with one or more IVF previous treatment failures, and the third arm included 66 younger poor responders. Main outcome measures were the number of oocytes and embryos, quality of embryos, and implantation and pregnancy rates.

RESULTS

In infertile women of advanced age, GH plus ovarian stimulation yielded no statistical differences in the numbers of oocytes and embryos, quality of embryo, and rates of implantation and pregnancy. In the second arm, the mature oocyte number (8.2 vs. 6.8), implantation rate (16.1% vs. 0%), and pregnancy rate (33.9% vs. 0%) in the GH cotreatment group differed significantly from those in the control group; the rate of good-quality embryos in the GH cotreatment group improved from 35.5% ± 31.1%-41.4% ± 30.6% in this arm. Similar results were observed in the third arm; in this arm, the clinical pregnancy rate was 30.3% in the GH cotreatment group and 6.1% in the control group.

CONCLUSION

No significant differences were observed in infertile women of advanced age, which may be due to the low GH dose. The GH adjuvant therapy for patients with one or more previous IVF treatment failures and for poor responders significantly improved the oocyte and embryo numbers as well as implantation and pregnancy rates.

Growth Hormone Ameliorates the Radiotherapy-Induced Ovarian Follicular Loss in Rats: Impact on Oxidative Stress, Apoptosis and IGF-1/IGF-1R Axis

Radiotherapy is one of the standard cytotoxic therapies for cancer. However, it has a profound impact on ovarian function leading to premature ovarian failure and infertility. Since none of the currently available methods for fertility preservation guarantees future fertility, the need for an effective radioprotective agent is highly intensified. The present study investigated the mechanisms of the potential radioprotective effect of growth hormone (GH) on γ irradiation-induced ovarian failure and the impact of the insulin like growth factor 1 (IGF-1) in the underlying protection. Immature female Sprague-Dawley rats were either exposed to single whole body irradiation (3.2 Gy) and/or treated with GH (1 mg/kg s.c). Experimental γ-irradiation produced an array of ovarian dysfunction that was evident by assessment of hormonal changes, follicular development, proliferation marker (PCNA), oxidative stress as well as apoptotic markers. In addition, IGF-1/IGF-1R axis expression was assessed using real-time PCR and immunolocalization techniques. Furthermore, after full maturity, fertility assessment was performed. GH significantly enhanced follicular development and restored anti-Mullerian hormone serum level as compared with the irradiated group. In addition, GH significantly ameliorated the deleterious effects of irradiation on oxidative status, PCNA and apoptosis. Interestingly, GH was shown to enhance the ovarian IGF-1 at transcription and translation levels, a property that contributes significantly to its radioprotective effect. Finally, GH regained the fertility that was lost following irradiation. In conclusion, GH showed a radioprotective effect and rescued the ovarian reserve through increasing local IGF-1 level and counteracting the oxidative stress-mediated apoptosis.

Efficacy of growth hormone supplementation with gonadotrophins in vitro fertilization for poor ovarian responders: an updated meta-analysis

Growth hormone (GH) is involved in the regulation of male and female infertility. Several clinical studies reveal that adjuvant GH treatment has a possible role in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI), especially in poor ovarian responders (POR) undergoing IVF/ICSI. Recent studies suggest that GH addition in POR patients significantly improves the rate of clinical pregnancy and live birth. Databases including PubMed, Embase, the Cochrane Central China National Knowledge Infrastructure (CNKI) and Google Scholar were searched for randomized controlled trials (RCTs) or controlled clinical trials (CCTs) on the effectiveness of GH supplementation with gonadotrophins in IVF/ICSI for POR. Two reviewers independently screened literature according to the inclusion and exclusion criteria, extracted data, and assessed methodological quality. Meta Analyst Beta 3.13 software was used to meta-analysis. Eleven studies (six RCTs and five CCTs) and 3788 subjects (613 subjects in cases group and 3175 subjects in controls group) were included in our study. The results of meta-analysis showed that GH addition significantly increased serum E2 level on the day of HCG (OR = 0.55; 95% CI = 0.127-0.973) and MII oocyte number (OR = 0.827; 95% CI = 0.470-1.184). Furthermore, GH addition significantly improved the number of 2PN (OR = 0.934; 95% CI = 0.206-1.661) and obtained embryos (OR = 0.934; 95% CI = 0.206-1.661). However, no significant difference was found for the overall implantation rate was 8.8% (95% CI = -0.062-0.237) and clinical pregnancy rate was 5.1% (95% CI = -0.033-0.134). The present result revel that GH supplementation for IVF/ICSI in POR increases the probability of serum E2 level on the day of HCG, the number of MII oocyte, 2PN and obtained embryos. However, GH addition does not increase implantation rate and clinical pregnancy rates. Due to the limited quantity and quality of the included studies as well as the difference in methodology, we suggest this above could be taken as a reference for clinical analysis which needs to be further evaluated in its effects.

Growth hormone and reproduction: a review of endocrine and autocrine/paracrine interactions

The somatotropic axis, consisting of growth hormone (GH), hepatic insulin-like growth factor I (IGF-I), and assorted releasing factors, regulates growth and body composition. Axiomatically, since optimal body composition enhances reproductive function, general somatic actions of GH modulate reproductive function. A growing body of evidence supports the hypothesis that GH also modulates reproduction directly, exerting both gonadotropin-dependent and gonadotropin-independent actions in both males and females. Moreover, recent studies indicate GH produced within reproductive tissues differs from pituitary GH in terms of secretion and action. Accordingly, GH is increasingly used as a fertility adjunct in males and females, both humans and nonhumans. This review reconsiders reproductive actions of GH in vertebrates in respect to these new conceptual developments.

A specific adenylyl cyclase inhibitor (DDA) and a cyclic AMP-dependent protein kinase inhibitor (H-89) block the action of equine growth hormone on in vitro maturation of equine oocytes

The objectives of this study were firstly to determine whether the stimulatory function of equine growth hormone (eGH) on equine oocyte maturation in vitro is mediated via cyclic adenosine monophosphate (cAMP); and secondly if the addition of eGH in vitro influences oocyte nuclear maturation and if this effect is removed when GH inhibitors are added to the culture. Cumulus–oocyte complexes (COCs) were recovered from follicles <25 mm in diameter and randomly allocated as follows: (i) control (no additives); and (ii) 400 ng/ml of eGH. A specific inhibitor against cyclic AMP-dependent protein kinase (H-89; 10−9, 10−11 or 10−15 M concentration) and a specific adenylate cyclase inhibitor, 2′,3′-dideoxyadenosine (DDA; 10−8, 10−10 or 10−14 M concentration) were used to observe whether they could block the eGH effect. After 30 h of in vitro maturation at 38.5°C with 5% CO2 in air, oocytes were stained with 10 μg/ml of Hoechst to evaluate nuclear status. More mature oocytes (P < 0.05) were detected when COCs were incubated with eGH (29 of 84; 34.5%) than in the control group (18 of 82; 21.9%). The H-89 inhibitor used at a concentration of 10−9 M (4 of 29; 13.8%) decreased (P < 0.05) the number of oocytes reaching nuclear maturation when compared with eGH (11 of 29; 38%). The DDA inhibitor at a concentration of 10−8 M (2 of 27; 7.4%) also reduced (P < 0.05) the number of oocytes reaching maturity when compared with the eGH group (9 of 30; 30%). Results from the present study show that H-89 and DDA can be used in vitro to block the eGH effect on equine oocyte maturation.

Metabolism and karyotype analysis of oocytes from patients with polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is associated with metabolic disturbances which include impaired insulin signalling and glucose metabolism in ovarian follicles. The oocyte is metabolically dependent upon its follicle environment during development, but it is unclear whether PCOS or polycystic ovarian (PCO) morphology alone affect oocyte metabolism and energy-demanding processes such as meiosis.

METHODS

Immature human oocytes were donated by PCOS (n = 14), PCO (n = 14) and control (n = 46) patients attending the assisted conception programme at Leeds Teaching Hospitals NHS Trust. Oocytes were cultured individually and carbohydrate metabolism was assessed during overnight in vitro maturation (IVM). Meiotic status was assessed and oocyte intracellular nicotinamide adenine dinucleotide phosphate (NAD(P)H) content and mitochondria activity were measured prior to karyotype analysis by multifluor in situ hybridization.

RESULTS

Patient aetiology had no significant effect on oocyte maturation potential or incidence of numerical chromosome abnormalities (44%), although PCOS and PCO oocytes were more likely to suffer predivision. Group G chromosomes were most likely to be involved in non-disjunction and predivision. PCOS was associated with increased glucose consumption (2.06 +/- 0.43 and 0.54 +/- 0.12 pmol/h for PCOS and control oocytes, respectively) and increased pyruvate consumption (18.4 +/- 1.2 and 13.9 +/- 0.9 pmol/h for PCOS and control oocytes, respectively) during IVM. Prior prescription of metformin significantly attenuated pyruvate consumption by maturing oocytes (8.5 +/- 1.8 pmol/h) from PCOS patients. Oocytes from PCO patients had intermediate metabolism profiles. Higher pyruvate turnover was associated with abnormal oocyte karyotypes (13.4 +/- 1.9 and 19.9 +/- 2.1 pmol/h for normal versus abnormal oocytes, respectively). Similarly, oocyte NAD(P)H content was 1.35-fold higher in abnormal oocytes.

CONCLUSIONS

The chromosomal constitution of in vitro matured oocytes from PCOS is similar to that of controls, but aspects of oocyte metabolism are perturbed by PCOS. Elevated pyruvate consumption was associated with abnormal oocyte karyotype.

Effect of growth hormone on oocyte competence in patients with multiple IVF failures

In a preliminary, unpublished randomized study conducted in 2000 on 39 patients, including a placebo group, it was observed that the addition of growth hormone (GH) during ovarian stimulation in patients with poor-quality oocytes increased the pregnancy rate. However, the results were not statistically significant due to the small number of patients in each group. A protocol with 8 IU GH was tested in 291 patients with three or more previous failures of embryo transfer for no clearly identifiable reasons. The analysis was restricted to patients receiving either recombinant FSH or human menopausal gonadotrophin (HMG) (n = 245). They were compared retrospectively to all patients with three or more failures during the same period of time but stimulated only with recombinant FSH or HMG, without GH, in an observational study design. Co-stimulation with GH gave better results in terms of number of oocytes collected and embryos obtained. Pregnancy rate per retrieval was higher than in the control group (25.7% versus 18.2%, P < 0.01) and reached a level similar to the one observed in the study centre for the whole population. Ovarian stimulation associated with GH can be proposed for patients with a history of repeated assisted reproduction failures. An improvement of cytoplasmic competence is proposed as an explanation.

Growth hormone and in vitro maturation of rhesus macaque oocytes and subsequent embryo development

PURPOSE

The objective of this study was to use a nonhuman primate model to examine the effects of growth hormone (GH) on oocyte in vitro maturation (IVM).

METHODS

Immunocytochemistry confirmed the presence of GH receptors in rhesus cumulus oocyte complexes and the cytoplasm of embryonic blastomeres. Recombinant human GH (r-hGH) was added to IVM medium and cumulus expansion, nuclear maturation, cytoplasmic maturation and embryo development were analyzed.

RESULTS

Cumulus expansion was highest in the presence of 1 and 10 ng/ml r-hGH. The addition of r-hGH during IVM increased the percentage of embryos progressing to at least the 9-16 cell stage. In a separate study, 100 ng/ml r-hGH was supplemented to IVM and embryo culture medium and no effect was observed.

CONCLUSIONS

The presence of GH receptors along with increased cumulus expansion and embryos progressing to the 9-16 cell stage supports the hypothesis that r-hGH may be involved in oocyte maturation.

Control of reproductive processes by growth hormone: extra- and intracellular mechanisms

Recent data on the association between growth hormone (GH) and male and female reproductive processes, as well as the effects of GH on these processes and on some reproductive and non-reproductive disorders, and possible extra- and intracellular mediators of its action are reviewed. The available data suggest that GH is an important endocrine and autocrine/paracrine regulator of reproduction. It controls proliferation, apoptosis, growth and differentiation and the secretory and generative activities of different reproductive organs. It also regulates their response to gonadotrophin-releasing hormone (GnRH) and gonadotropins. Despite the effects of GH on the IGF/IGFBP (insulin-like growth factor binding protein) system, oxytocin, steroids, activin, gonadotropin and gonadotropin receptors, the majority of GH's actions on the reproductive processes are probably mediated not by these substances but by specific GH receptors acting through cAMP/protein kinase A, protein kinase G, tyrosine kinase-, MAP kinase and CDC2 kinase-dependent intracellular mechanisms. Although GH treatments can increase the risk of some reproductive and non-reproductive disorders, they may be useful in improving gonadal function, inducing superovulation and in embryo production.

Improvement of delivery and live birth rates after ICSI in women aged >40 years by ovarian co-stimulation with growth hormone

BACKGROUND

Growth hormone (GH) is required for ovarian follicular development, and its administration during ovarian stimulation improves pregnancy rate in cow and sheep. Data on the use of exogenous GH in human assisted reproduction treatment are inconsistent. This prospective randomized study evaluates the usefulness of GH administration in women of >40 years undergoing ovarian stimulation for assisted reproduction treatment.

METHODS

One hundred women of >40 years undergoing assisted reproduction treatment were randomized between a GH treatment group and a placebo group. Assisted reproduction treatment outcomes were evaluated.

RESULTS

In patients of the GH treatment group, a similar number of oocytes, embryos and pregnancies was achieved as compared with the placebo group. However, the patients treated with GH suffered fewer pregnancy losses, resulting in higher delivery and live birth rates. These patients also showed higher peak serum estradiol concentration and higher concentrations of GH and estradiol in pre-ovulatory follicular fluid as compared with the placebo group.

CONCLUSIONS

Administration of GH during ovarian stimulation alleviates age-related decrease in assisted reproduction treatment efficiency. This effect appears to be mainly due to an improvement of oocyte developmental potential, but GH action on the uterus cannot be excluded.

The role of growth hormone in fetal development

Studies across several species, particularly the mouse, show that growth hormone (GH, somatotrophin) is an important determinant of litter size, and to a lesser extent, of birth length. GH acts at all stages of development, from ovulation through preimplantation development to the late fetus, with actions on both embryo/fetus and mother contributing to successful fetal development. The fact that these are not more obvious in vivo is likely a result of redundancy of cytokine hormone action, particularly in relation to prolactin, which shares common actions and receptor locations with GH.