Assisted conception using buserelin and human menopausal gonadotrophins in women with polycystic ovary syndrome

Polycystic ovary syndrome: pathophysiology and therapeutic opportunities

Polycystic ovary syndrome is characterised by excessive levels of androgens and ovulatory dysfunction, and is a common endocrine disorder in women of reproductive age. Polycystic ovary syndrome arises as a result of polygenic susceptibility in combination with environmental influences that might include epigenetic alterations and in utero programming. In addition to the well recognised clinical manifestations of hyperandrogenism and ovulatory dysfunction, women with polycystic ovary syndrome have an increased risk of adverse mental health outcomes, pregnancy complications, and cardiometabolic disease. Unlicensed treatments have limited efficacy, mostly because drug development has been hampered by an incomplete understanding of the underlying pathophysiological processes. Advances in genetics, metabolomics, and adipocyte biology have improved our understanding of key changes in neuroendocrine, enteroendocrine, and steroidogenic pathways, including increased gonadotrophin releasing hormone pulsatility, androgen excess, insulin resistance, and changes in the gut microbiome. Many patients with polycystic ovary syndrome have high levels of 11-oxygenated androgens, with high androgenic potency, that might mediate metabolic risk. These advances have prompted the development of new treatments, including those that target the neurokinin-kisspeptin axis upstream of gonadotrophin releasing hormone, with the potential to lessen adverse clinical sequelae and improve patient outcomes.

Novel Concepts for Inducing Final Oocyte Maturation in In Vitro Fertilization Treatment

Infertility affects one in six of the population and increasingly couples require treatment with assisted reproductive techniques. In vitro fertilization (IVF) treatment is most commonly conducted using exogenous FSH to induce follicular growth and human chorionic gonadotropin (hCG) to induce final oocyte maturation. However, hCG may cause the potentially life-threatening iatrogenic complication "ovarian hyperstimulation syndrome" (OHSS), which can cause considerable morbidity and, rarely, even mortality in otherwise healthy women. The use of GnRH agonists (GnRHas) has been pioneered during the last two decades to provide a safer option to induce final oocyte maturation. More recently, the neuropeptide kisspeptin, a hypothalamic regulator of GnRH release, has been investigated as a novel inductor of oocyte maturation. The hormonal stimulus used to induce oocyte maturation has a major impact on the success (retrieval of oocytes and chance of implantation) and safety (risk of OHSS) of IVF treatment. This review aims to appraise experimental and clinical data of hormonal approaches used to induce final oocyte maturation by hCG, GnRHa, both GnRHa and hCG administered in combination, recombinant LH, or kisspeptin. We also examine evidence for the timing of administration of the inductor of final oocyte maturation in relationship to parameters of follicular growth and the subsequent interval to oocyte retrieval. In summary, we review data on the efficacy and safety of the major hormonal approaches used to induce final oocyte maturation in clinical practice, as well as some novel approaches that may offer fresh alternatives in future.

Clinical parameters of ovarian hyperstimulation syndrome following different hormonal triggers of oocyte maturation in IVF treatment

OBJECTIVE

Ovarian hyperstimulation syndrome (OHSS) is a serious iatrogenic condition, predominantly related to the hormone used to induce oocyte maturation during IVF treatment. Kisspeptin is a hypothalamic neuropeptide that has recently been demonstrated to safely trigger final oocyte maturation during IVF treatment even in women at high risk of OHSS. However, to date, the safety of kisspeptin has not been compared to current hormonal triggers of oocyte maturation.

DESIGN

We conducted a retrospective single-centre cohort study investigating symptoms and clinical parameters of early OHSS in women at high risk of OHSS (antral follicle count or total number of follicles on day of trigger ≥23) triggered with human chorionic gonadotrophin (hCG) (n = 40), GnRH agonist (GnRHa; n = 99) or kisspeptin (n = 122) at Hammersmith Hospital IVF unit, London, UK (2013-2016).

RESULTS

Clinical Parameters of OHSS: Median ovarian volume was larger following hCG (138 ml) than GnRHa (73 ml; P < .0001), and in turn kisspeptin (44 ml; P < .0001). Median ovarian volume remained enlarged 20-fold following hCG, 8-fold following GnRHa and 5-fold following kisspeptin compared to prestimulation ovarian volumes. Mean (±SD) ascitic volumes were lesser following GnRHa (9 ± 44 ml) and kisspeptin (5 ± 8 ml) than hCG (62 ± 84 ml; P < .0001). Symptoms of OHSS were most frequent following hCG and least frequent following kisspeptin. Diagnosis of OHSS: The odds ratio for OHSS diagnosis was 33.6 (CI 12.6-89.5) following hCG and 3.6 (CI 1.8-7.1) following GnRHa, when compared to kisspeptin.

CONCLUSION

Triggering oocyte maturation by inducing endogenous gonadotrophin release is preferable to the use of exogenous hCG in women at high risk of OHSS.

A second dose of kisspeptin-54 improves oocyte maturation in women at high risk of ovarian hyperstimulation syndrome: a Phase 2 randomized controlled trial

STUDY QUESTION

Can increasing the duration of LH-exposure with a second dose of kisspeptin-54 improve oocyte maturation in women at high risk of ovarian hyperstimulation syndrome (OHSS)?

SUMMARY ANSWER

A second dose of kisspeptin-54 at 10 h following the first improves oocyte yield in women at high risk of OHSS.

WHAT IS KNOWN ALREADY

Kisspeptin acts at the hypothalamus to stimulate the release of an endogenous pool of GnRH from the hypothalamus. We have previously reported that a single dose of kisspeptin-54 results in an LH-surge of ~12-14 h duration, which safely triggers oocyte maturation in women at high risk of OHSS.

STUDY DESIGN, SIZE, DURATION

Phase-2 randomized placebo-controlled trial of 62 women at high risk of OHSS recruited between August 2015 and May 2016. Following controlled ovarian stimulation, all patients (n = 62) received a subcutaneous injection of kisspeptin-54 (9.6 nmol/kg) 36 h prior to oocyte retrieval. Patients were randomized 1:1 to receive either a second dose of kisspeptin-54 (D; Double, n = 31), or saline (S; Single, n = 31) 10 h thereafter. Patients, embryologists, and IVF clinicians remained blinded to the dosing allocation.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Study participants: Sixty-two women aged 18-34 years at high risk of OHSS (antral follicle count ≥23 or anti-Mullerian hormone level ≥40 pmol/L). Setting: Single centre study carried out at Hammersmith Hospital IVF unit, London, UK. Primary outcome: Proportion of patients achieving an oocyte yield (percentage of mature oocytes retrieved from follicles ≥14 mm on morning of first kisspeptin-54 trigger administration) of at least 60%. Secondary outcomes: Reproductive hormone levels, implantation rate and OHSS occurrence.

MAIN RESULTS AND THE ROLE OF CHANCE

A second dose of kisspeptin-54 at 10 h following the first induced further LH-secretion at 4 h after administration. A higher proportion of patients achieved an oocyte yield ≥60% following a second dose of kisspeptin-54 (Single: 14/31, 45%, Double: 21/31, 71%; absolute difference +26%, CI 2-50%, P = 0.042). Patients receiving two doses of kisspeptin-54 had a variable LH-response following the second kisspeptin dose, which appeared to be dependent on the LH-response following the first kisspeptin injection. Patients who had a lower LH-rise following the first dose of kisspeptin had a more substantial 'rescue' LH-response following the second dose of kisspeptin. The variable LH-response following the second dose of kisspeptin resulted in a greater proportion of patients achieving an oocyte yield ≥60%, but without also increasing the frequency of ovarian over-response and moderate OHSS (Single: 1/31, 3.2%, Double: 0/31, 0%).

LIMITATIONS, REASONS FOR CAUTION

Further studies are warranted to directly compare kisspeptin-54 to more established triggers of oocyte maturation.

WIDER IMPLICATIONS OF THE FINDINGS

Triggering final oocyte maturation with kisspeptin is a novel therapeutic option to enable the use of fresh embryo transfer even in the woman at high risk of OHSS.

STUDY FUNDING/COMPETING INTEREST(S)

The study was designed, conducted, analysed and reported entirely by the authors. The Medical Research Council (MRC), Wellcome Trust & National Institute of Health Research (NIHR) provided research funding to carry out the studies. There are no competing interests to declare.

TRIAL REGISTRATION NUMBER

Clinicaltrial.gov identifier NCT01667406.

TRIAL REGISTRATION DATE

8 August 2012.

DATE OF FIRST PATIENT'S ENROLMENT

10 August 2015.

Kisspeptin across the human lifespan:evidence from animal studies and beyond

Since its first description in 1996, the KISS1 gene and its peptide products, kisspeptins, have increasingly become recognised as key regulators of reproductive health. With kisspeptins acting as ligands for the kisspeptin receptor KISS1R (previously known as GPR54 or KPR54), recent work has consistently shown that administration of kisspeptin across a variety of species stimulates gonadotrophin release through influencing gonadotrophin-releasing hormone secretion. Evidence from both animal and human studies supports the finding that kisspeptins are crucial for ensuring healthy development, with knockout animal models, as well as proband genetic testing in human patients affected by abnormal pubertal development, corroborating the notion that a functional kisspeptin receptor is required for appropriate gonadotrophin secretion. Given the large body of evidence that exists surrounding the influence of kisspeptin in a variety of settings, this review summarises our physiological understanding of the role of these important peptides and their receptors, before proceeding to describe the varying role they play across the reproductive lifespan.

Efficacy of Kisspeptin-54 to Trigger Oocyte Maturation in Women at High Risk of Ovarian Hyperstimulation Syndrome (OHSS) During In Vitro Fertilization (IVF) Therapy

CONTEXT

In vitro fertilization (IVF) treatment is an effective therapy for infertility, but can result in the potentially life-threatening complication, ovarian hyperstimulation syndrome (OHSS).

OBJECTIVE

This study aimed to investigate whether kisspeptin-54 can be used to effectively and safely trigger oocyte maturation in women undergoing IVF treatment at high risk of developing OHSS.

SETTING AND DESIGN

This was a phase 2, multi-dose, open-label, randomized clinical trial of 60 women at high risk of developing OHSS carried out during 2013-2014 at Hammersmith Hospital IVF unit, London, United Kingdom.

INTERVENTION

Following a standard recombinant FSH/GnRH antagonist protocol, patients were randomly assigned to receive a single injection of kisspeptin-54 to trigger oocyte maturation using an adaptive design for dose allocation (3.2 nmol/kg, n = 5; 6.4 nmol/kg, n = 20; 9.6 nmol/kg, n = 15; 12.8 nmol/kg, n = 20). Oocytes were retrieved 36 h after kisspeptin-54 administration, assessed for maturation, and fertilized by intracytoplasmic sperm injection with subsequent transfer of one or two embryos. Women were routinely screened for the development of OHSS.

MAIN OUTCOME MEASURE

Oocyte maturation was measured by oocyte yield (percentage of mature oocytes retrieved from follicles ≥ 14 mm on ultrasound). Secondary outcomes include rates of OHSS and pregnancy.

RESULTS

Oocyte maturation occurred in 95% of women. Highest oocyte yield (121%) was observed following 12.8 nmol/kg kisspeptin-54, which was +69% (confidence interval, -16-153%) greater than following 3.2 nmol/kg. At all doses of kisspeptin-54, biochemical pregnancy, clinical pregnancy, and live birth rates per transfer (n = 51) were 63, 53, and 45%, respectively. Highest pregnancy rates were observed following 9.6 nmol/kg kisspeptin-54 (85, 77, and 62%, respectively). No woman developed moderate, severe, or critical OHSS.

CONCLUSION

Kisspeptin-54 is a promising approach to effectively and safely trigger oocyte maturation in women undergoing IVF treatment at high risk of developing OHSS.

The use of gonadotropin-releasing hormone (GnRH) agonist to induce oocyte maturation after cotreatment with GnRH antagonist in high-risk patients undergoing in vitro fertilization prevents the risk of ovarian hyperstimulation syndrome: a prospective randomized controlled study

OBJECTIVE

To determine whether there are any differences in the incidence of ovarian hyperstimulation syndrome (OHSS) and implantation rates in high-risk patients undergoing IVF using a protocol consisting of GnRH agonist trigger after cotreatment with GnRH antagonist or hCG trigger after dual pituitary suppression protocol.

DESIGN

Prospective randomized controlled trial.

SETTING

University-based tertiary fertility center.

PATIENT(S)

Sixty-six patients under 40 years of age with polycystic ovarian syndrome, polycystic ovarian morphology, or previous high response undergoing IVF.

INTERVENTION(S)

Patients were randomized to an ovarian stimulation protocol consisting of either GnRH agonist trigger after cotreatment with GnRH antagonist (study group) or hCG trigger after dual pituitary suppression with a GnRH agonist (control group). Both groups received luteal phase and early pregnancy supplementation with IM progesterone (P), and patients in the study group also received E(2) patches and their doses were adjusted according to the serum levels.

MAIN OUTCOME MEASURE(S)

Incidence of OHSS and implantation rate.

RESULT(S)

None of the patients in the study group developed any form of OHSS compared with 31% (10/32) of the patients in the control group. There were no significant differences in the implantation (22/61 [36.0%] vs. 20/64 [31.0%]), clinical pregnancy (17/30 [56.7%] vs. 15/29 [51.7%]), and ongoing pregnancy rates (16/30 [53.3%] vs. 14/29 [48.3%]) between the study and control groups, respectively.

CONCLUSION(S)

The use of a protocol consisting of GnRH agonist trigger after GnRH antagonist cotreatment combined with adequate luteal phase and early pregnancy E(2) and P supplementation reduces the risk of OHSS in high-risk patients undergoing IVF without affecting implantation rate.

Polycystic ovaries and ovarian hyperstimulation syndrome: a systematic review*

OBJECTIVES

To assess and quantify the relationship between polycystic ovaries (PCOs) and ovarian hyperstimulation syndrome (OHSS).

DATA SOURCES

Published studies, any language, identified through MEDLINE, EMBASE, BIOSIS, Web of Science, and bibliographies. Studies were selected if exposure (ultrasound findings of PCO before treatment) and outcome (OHSS) could be abstracted to two-by-two tables.

RESULTS

Ten studies, meeting inclusion and exclusion criteria, were analyzed. When PCO were present, the combined odds ratio for OHSS was 6.8 (95% confidence interval 4.9-9.6).

CONCLUSION

There is a significant and consistent relationship between PCO and OHSS. When PCO are present before treatment with assisted reproduction, deliberate policies to moderate treatment appear justified.

Use of luteinizing hormone releasing hormone agonists in polycystic ovary syndrome

Luteinizing hormone releasing hormone (LHRH) agonists have been used in conjunction with gonadotrophins, and occasionally with pulsatile LHRH, for ovulation induction in women with clomiphene-citrate-resistant polycystic ovary syndrome (PCOS) and also for superovulation for in vitro fertilization (IVF) and gamete intrafallopian transfer in women with PCOS. In IVF, LHRH agonists given by the 'long protocol' before gonadotrophins are commenced have consistently shown higher pregnancy rates and higher live birth rates. Although the optimal time to commence LHRH agonist is not clearly determined, commencement in the early follicular phase possibly with pre-treatment with the combined oral contraceptive pill would avoid the risk of inadvertent administration during early pregnancy. The role of LHRH agonists in ovulation induction is less clear cut, although there may be some advantages in patients with refractory PCOS. The role of LHRH agonists in ovarian hyperstimulation syndrome and recurrent miscarriage is also discussed.

Diagnosis, prevention and management of ovarian hyperstimulation syndrome

The overall incidence of clinically important (moderate to severe) OHSS ranges from 1% to 10% of IVF cycles, but only a small proportion (0.5% to 2%) of the cases are severe. In extreme but rare cases, secondary complications such as deep vein thrombosis, respiratory distress and acute hepato-renal failure may occur. The main risk factors are the presence of polycystic ovaries, high ovarian response to superovulation therapy, the use of hCG to trigger the ovulatory process or for luteal phase support, and the endogenous production of hCG by an early pregnancy. The pathogenesis of OHSS is unknown, although the predominant biochemical mediator is thought to be the renin-angiotensin system. Ovarian stimulation should always be carefully monitored to identify those women at risk. In IVF cycles, the hCG injection should be withheld if the risk is judged to be too great. Some women will benefit from a policy of proceeding to collect oocytes, but electively cryopreserving any resulting embryos, thus allowing the ovarian stimulation cycle not to be wasted. The administration of albumin at the time of oocyte collection will reduce the chance of severe OHSS occurring. If a decision is made to proceed with oocyte recovery and embryo transfer, it may be advisable to give 5000 IU of hCG, rather than 10,000 IU, as the ovulatory trigger. Progesterone, and not hCG, should be given in the luteal phase. Women developing mild or moderate OHSS should be kept under outpatient surveillance to detect the minority that may progress to severe OHSS. Those with severe OHSS should be hospitalised for fluid and electrolyte management. Paracentesis under ultrasound guidance is recommended where there are tense ascites, but further surgical intervention should rarely be undertaken and only when there is good clinical evidence of ovarian torsion or haemorrhage.

Reproductive health and polycystic ovary syndrome

Women with hyperandrogenic disorders represent a unique group among those with infertility due to anovulation. Although antiestrogens are effective in restoring ovulation in most women, it remains unclear whether these treatments restore fecundability per ovulatory cycle and the ability to maintain pregnancy in these individuals. Moreover, antiestrogens are ineffective in restoring ovulation in some hyperandrogenic anovulatory women, whose condition poses unique and vexing challenges for the infertility therapist. Gonadotropin treatment in antiestrogen-resistant women often leads to ovarian hyperstimulation syndrome, which has been addressed by modification of dosing schedules (e.g., low-dose administration), pretreatment with gonadotropin-releasing hormone (GnRH) analogs, and elimination of luteinizing hormone from the administered gonadotropins. Surgical reduction in ovarian volume has met with some success, although there may be a risk of inducing surgical adhesions of the adnexa. The second major reproductive adversity facing these patients is their elevated risk of endometrial cancer. Unopposed estrogen exposure probably contributes to this risk, but hyperandrogenicity and hyperinsulinism may act independently or in concert with estrogen to amplify the risk in these women. While the risks and strategies for preventive care in these women need to be better defined, reproductive health specialists are urged to continue using presently accepted measures, including education, to maintain these women's reproductive health.