GnRH-agonists in fertility preservation

Role of Stem Cells in the Ovarian Tissue Cryopreservation and Transplantation for Fertility Preservation

Although the cancer survival rate has increased, cancer treatments, including chemotherapy and radiotherapy, can cause ovarian failure and infertility in women of reproductive age. Preserving fertility throughout cancer treatment is critical for maintaining quality of life. Fertility experts should propose individualized fertility preservation methods based on the patient’s marital status, pubertal status, partner status, and the urgency of treatment. Widely practiced fertility preservation methods, including ovarian transposition and embryo and oocyte cryopreservation, are inappropriate for prepubertal girls or those needing urgent initiation of cancer treatment. Ovarian tissue cryopreservation and transplantation, an emerging new technology, may be a solution for these cancer patients. The use of stem cells in ovarian tissue cryopreservation and transplantation increases oxygenation, angiogenesis, and follicle survival rates. This review discusses the recent advances in ovarian tissue cryopreservation and transplantation with special focus on the use of stem cells to improve fertilization techniques.

Current Understanding of the Etiology, Symptomatology, and Treatment Options in Premature Ovarian Insufficiency (POI)

Premature ovarian insufficiency (POI) occurs in at least 1% of all women and causes life-long health problems and psychological stress. Infertility caused by POI used to be considered absolute, with infertility treatment having little or no value. Generally, it has been thought that medicine can provide little service to these patients. The etiology of POI has been found to be genetic, chromosomal, and autoimmune. In addition, the increasing numbers of cancer survivors are candidates for iatrogenic POI, along with patients who have undergone ovarian surgery, especially laparoscopic surgery. Over 50 genes are known to be causally related to POI, and the disease course of some cases has been clarified, but in most cases, the genetic background remains unexplained, suggesting that more genes associated with the etiology of POI need to be discovered. Thus, in most cases, the genetic background of POI has not been clarified. Monosomy X is well known to manifest as Turner's syndrome and is associated with primary amenorrhea, but recent studies have shown that some women with numerical abnormalities of the X chromosome can have spontaneous menstruation up to their twenties and thirties, and some even conceive. Hormone replacement therapy (HRT) is recommended for women with POI from many perspectives. It alleviates vasomotor and genitourinary symptoms and prevents bone loss and cardiovascular disease. POI has been reported to reduce quality of life and life expectancy, and HRT may help improve both. Most of the problems that may occur with HRT in postmenopausal women do not apply to women with POI; thus, in POI, HRT should be considered physiological replacement of estrogen (+progesterone). This review describes some new approaches to infertility treatment in POI patients that may lead to new treatments for POI, along with the development of more sensitive markers of secondary/preantral follicles and genetic diagnosis.

Fertility Preservation Using GnRH Agonists: Rationale, Possible Mechanisms, and Explanation of Controversy

The only clinically accepted method of fertility preservation in young women facing gonadotoxic chemo- and/or radiotherapy for malignant or autoimmune diseases is cryopreservation of embryos or unfertilized ova, whereas cryopreservation of ovarian tissue for future reimplantation, or in vitro maturation of follicles, and the use of gonadotropin-releasing hormone agonists (GnRHa) are still considered investigational, by several authorities. Whereas previous publications have raised the fear of GnRHa's possible detrimental effects in patients with hormone receptor-positive breast cancers, recent randomized controlled trials (RCTs) have shown that it either improves or does not affect disease-free survival (DFS) in such patients. This review summarizes the pros and cons of GnRHa co-treatment for fertility preservation, suggesting 5 theoretical mechanisms for GnRHa action: (1) simulating the prepubertal hypogonadotropic milieu, (2) direct effect on GnRH receptors, (3) decreased ovarian perfusion, (4) upregulation of an ovarian-protecting molecule such as sphingosine-1-phosphate, and (5) protecting a possible germinative stem cell. We try to explain the reasons for the discrepancy between most publications that support the use of GnRHa for fertility preservation and the minority of publications that did not support its efficiency.

Preserving fertility when choosing chemotherapy regimens - the role of gonadotropin-releasing hormone agonists

INTRODUCTION

The late effects of cancer treatment have recently gained a worldwide ubiquitous interest among reproductive endocrinologists, oncologists, and all health care providers. Despite many publications on this subject, there are many equivocal issues necessitating summary. The case for and against using GnRH-agonist for fertility preservation is summarized with the rationale that preventing ovarian failure may be better than treating it.

AREAS COVERED

We searched Medline in the last 10 years using terms: 'fertility preservation', 'female chemotherapy', 'Gonadotropin-releasing hormone (GnRH) analogues', 'GnRH agonists' 'gonadotoxicity', and 'cancer treatment'. We included mainly publications from the past 7 years, but did not exclude previous, commonly referenced publications. Here, we summarize the various methods available for fertility preservation and minimizing chemotherapy induced gonadotoxicity.

EXPERT OPINION

Until now, 20 studies (15 retrospective and 5 randomized controlled trial) have reported on 2038 patients treated with GnRH-a in parallel to chemotherapy, showing a significant decrease in premature ovarian failure (POF) rate in survivors versus 8 studies reporting on 509 patients, with negative results. Patients treated with GnRH-a in parallel to chemotherapy preserved their cyclic ovarian function in 91% of cases as compared to 41% of controls, with a pregnancy rate of 19 - 71% in the treated patients. Furthermore, over 10 recent meta-analyses have concluded that GnRH-a are beneficial and may decrease the risk of POF in survivors. Because most of the methods involving ovarian or egg cryopreservation are not yet clinically established and unequivocally successful, these young patients deserve to be informed with all the various modalities to minimize gonadal damage and preserve ovarian function and future fertility. Combining the various modalities for a specific patient may increase the odds of preservation of future fertility.

'An ounce of prevention is worth a pound of cure': the case for and against GnRH-agonist for fertility preservation

The late effects of cancer treatment have recently gained a worldwide interest among reproductive endocrinologists, oncologists, and all health-care providers, and the protection against iatrogenic infertility caused by chemotherapy assumes a high priority. Here, we summarize the case for and against using GnRH-agonist for fertility preservation and minimizing chemotherapy-induced gonadotoxicity. The rationale and philosophy supporting its use is that preventing premature ovarian failure (POF) is preferable to treating it, following the dictum: 'an ounce of prevention is worth a pound of cure'. Despite many publications on this subject, there are many equivocal issues necessitating summary. Until now, 20 studies (15 retrospective and 5 randomized, controlled trials) have reported on 1837 patients treated with GnRH-a in parallel to chemotherapy, showing a significant decrease in POF rate in survivors versus 9 studies reporting on 593 patients, with results not supporting GnRH-a use. Patients treated with GnRH-a in parallel to chemotherapy preserved their cyclic ovarian function in 91% of cases when compared with 41% of controls, with a pregnancy rate of 19-71% in the treated patients. Furthermore, seven meta-analyses have concluded that GnRH-a are beneficial and may decrease the risk of POF in survivors. However, controversy still remains regarding the efficiency of GnRH-a in preserving fertility. Since not all the methods involving fertility preservation are unequivocally successful and safe, these young patients deserve to be informed of all the various modalities to minimize gonadal damage and preserve ovarian function and future fertility. Combining several methods for a specific patient may increase the odds for minimally invasive fertility preservation.

More research, more responsibility: the expansion of duty to warn in cancer patients considering fertility preservation

Reproductive technology is advancing at a steadfast pace. Researchers are successfully refining options for fertility preservation, to the benefit of the cancer community. Research has consistently shown cancer patients and survivors desire to have risks to fertility and preservation options disclosed, and major campaigns have been undertaken to refer these patients to fertility specialists. However, the decision to pursue fertility preservation is not an isolated judgment. A variety of future decisions may arise for the individual or couple, choices that may not have been relayed during the initial decision-making process. Future decisions include the length of time to continue to store frozen gametes, donating banked gametes to infertile couples, and whether embryos created with one partner would be accepted by a new partner. It is important to continue the advancement of fertility preservation not only in the scientific milieu, but also in addressing a patient's preparedness for long-term decision making.

The impact of cyclophosphamide on menstruation and pregnancy in women with rheumatologic disease

Background

While cyclophosphamide (CYC) can save the life of a young woman with severe rheumatologic disease, it may lead to the long-term side-effects of infertility and premature menopause. We compared the reproductive health histories of young women with rheumatologic disease with and without prior CYC exposure to identify the impact of this medication on this important component of health.

Methods

This research includes a case-series study of women diagnosed with SLE, vasculitis, and scleroderma prior to age 35. Each patient completed a questionnaire about desired childbearing, menstrual regularity, infertility, and pregnancy history. Women with prior CYC therapy were queried about the use of gonadotropin-releasing hormone agonists (GnRH-a) for fertility preservation. The responses to this questionnaire were compared for women with and without CYC exposure.

Results

Of the 43 participants, 23 had prior CYC exposure and 20 were CYC naïve. The current age of these groups was similar (average age 32), but women with prior CYC were four years younger at diagnosis than women without CYC. More women with prior CYC had cessation of menses in the year prior to the study (30.4% vs 0%, p < 0.05). Of the women with prior CYC exposure, those with loss of menses were older at study enrollment, older at CYC treatment, and had a higher cumulative CYC dose than those with preserved menstruation. While more women with GnRH-a co-therapy during CYC had maintained menses, this difference did not reach statistical significance. Women with prior CYC without GnRH-a co-therapy had a higher frequency of nulliparity and had greater trouble conceiving than women with GnRH-a co-therapy. Few pregnancies were conceived following CYC exposure and all resulted in elective termination, miscarriage, or preterm birth.

Conclusion

In this cohort of young women with rheumatologic disease, more women with prior CYC than without had amenorrhea, nulliparity, and infertility. GnRH-a co-therapy may prevent these adverse effects of CYC.

Gonadotropin-releasing hormone agonist may minimize premature ovarian failure in young women undergoing autologous stem cell transplantation

OBJECTIVE

To compare the rate of premature ovarian failure (POF) after stem cell transplantation (SCT) in young women receiving GnRH-agonist (GnRH-a) in conjunction with gonadotoxic chemotherapy.

DESIGN

Prospective, nonrandomized study.

SETTING

Tertiary university hospital.

PATIENT(S)

Ninety-five women received conditioning chemotherapy, with or without GnRH-a before SCT. Complete information was available for only 83 patients.

INTERVENTION(S)

Conditioning chemotherapy, with or without GnRH-a before SCT.

MAIN OUTCOME MEASURE(S)

Cyclic ovarian function (COF) or POF after SCT.

RESULT(S)

There were no significant differences in age, chemotherapy treatment, or diagnoses between the study and control groups. In the GnRH-a group, 38.3% (18/47) patients resumed COF, compared with 11.1% (4/36) for patients who did not receive GnRH-a. Patients who resumed COF were on average 3.7 years (median, 3 years) younger at the time of transplantation than those who experienced POF. GnRH-a had a significant effect on long-term COF in patients with lymphomas (66.7% [14/21] for GnRH-a group vs. 18.2% [2/11] for control) but not for leukemia patients.

CONCLUSION(S)

GnRH-a cotreatment in conjunction with conditioning chemotherapy before SCT may significantly decrease the gonadotoxicity and POF from 82% to 33% in lymphoma but not in leukemia patients.

Chemotherapy and fertility

The overall increase in cancer prevalence and the significant increase in long-term survival have generated worldwide interest in preserving fertility in young women exposed to gonadotoxic chemo- and radiotherapy. Infertility represents one of the main long-term consequences of combination chemotherapy given for lymphoma, leukaemia and other malignancies in young women. The gonadotoxic effect of various chemotherapeutic agents is diverse, may involve a variety of pathophysiologic mechanisms, and is not unequivocally understood. Proliferating cells, such as in tissues with high turnover (i.e. bone marrow, gastrointestinal tract and growing ovarian follicles) are more vulnerable to the toxic effect of alkylating agents. These agents may also be cytotoxic to cells at rest, as they are not cell-cycle specific. Alkylating agents, the most gonadotoxic chemotherapeutic medications, cause dose-dependent, direct destruction of oocytes and follicular depletion, and may bring about cortical fibrosis and ovarian blood-vessel damage. The reported rate of premature ovarian failure after various diseases and chemotherapeutic protocols differ enormously, and depend mainly on the chemotherapeutic protocol used and age range of the woman. Several options have been proposed for preserving female fertility, despite gonadotoxic chemotherapy: ovarian transposition, cryopreservation of embryos, unfertilised metaphase-II oocytes and ovarian tissue, and administration of gonadotropin-releasing hormone agonistic analogs in an attempt to decrease the gonadotoxic effects of chemotherapy by simulating a prepubertal hormonal milieu. None of these methods is ideal and none guarantees future fertility in all survivors; therefore, a combination of methods is recommended for maximising women's chances of future fertility.

Preservation of ovarian function and minimizing premature ovarian failure during chemotherapy using gonadotropin-releasing hormone analogs

Evaluation of: Del Mastro L, Boni L, Michelotti A et al. Effect of the gonadotropin-releasing hormone analogue triptorelin on the occurrence of chemotherapy-induced early menopause in premenopausal women with breast cancer: a randomized trial. JAMA 306(3), 269-276 (2011). This study is a randomized, open-label, Phase III trial, conducted in 16 Italian centers that enrolled 281 patients between 2003 and 2008. The recruited patients were prospectively and randomly allocated to either chemotherapy alone or combined with monthly triptorelin gonadotropin-releasing hormone analog, started before chemotherapy and repeated every month throughout chemotherapy. The clinical and tumor characteristics of the patients in the control or treatment groups were similar. A total of 12 months after ending chemotherapy, the premature ovarian failure rate was 25.9% in the chemotherapy-alone group versus 8.9% in the chemotherapy and gonadotropin-releasing hormone analog group, an absolute difference of -17% (95% CI: -26 to -7.9%; p < 0.001). The odds ratio for treatment-induced premature ovarian failure was 0.28 (95% CI: 0.14-0.59; p < 0.001). The authors concluded that use of gonadotropin-releasing hormone analog chemotherapy in premenopausal breast cancer patients can significantly reduce the occurrence of chemotherapy-induced early menopause.

Optimizing potential for fertility: fertility considerations for the pediatrician

Whether for the prepubertal or pubertal child, the goal of fertility preservation is to obtain cells or tissues to be used to produce future children. For the prepubertal child, preservation efforts involve germ cells, earlier forms of sperm, and immature follicles, rather than mature spermatozoa or follicles. Options for prepubertal children include for boys freezing testicular tissue and extracting testicular sperm or for girls obtaining ovarian cortical or follicular tissue for storage. These procedures involve extraction and storage of immature gametes for subsequent in vitro maturation, although attempts for sperm currently involve only animal studies. For adolescent subjects who have sufficient gonadal development and reserve, sperm, oocytes, and ovarian cortex can be retrieved as among adults.

Depot GnRH-agonist trigger for breast-cancer patient undergoing ovarian stimulation resulted in mature oocytes for cryopreservation: a case report

This report describes the case of a 27-year-old woman with breast cancer who underwent ovarian stimulation for fertility preservation with recombinant FSH in conjunction with a gonadotrophin-releasing hormone (GnRH) antagonist and an aromatase inhibitor from the beginning of the treatment. A 3.75-mg triptorelin depot formulation was given intramuscularly when the follicular diameter of three follicles reached ≥ 20 mm and a total of 13 follicles reached ≥ 15 mm. Oocyte retrieval was scheduled for 36 h later and 10 mature oocytes were collected and vitrified. This case report demonstrates that a depot GnRH-agonist trigger effectively leads to mature oocyte retrieval, with the advantage of initiating ovarian suppression for the purpose of fertility preservation during adjuvant chemotherapy in breast-cancer patients.

Tamoxifen decreases ovarian follicular loss from experimental toxicant DMBA and chemotherapy agents cyclophosphamide and doxorubicin in the rat

INTRODUCTION

we serendipitously observed a protective effect of tamoxifen against depletion of ovarian follicles by 7,12-dimethylbenzanthracene (DMBA), a chemical carcinogen, during a cancer prevention study. Such ovarian protection is being sought as an alternative approach to fertility preservation in human cancer patients.

METHODS

rats received tamoxifen (0, 1 mg or 2.5 mg/kg/d) and DMBA (0, 1, 2 mg/kg/wk) or cyclophosphamide (0, 35, 50 mg/kg/wk). Ovarian follicles were quantified and effects on fertility and litter size were tested. Cultured oocytes were exposed to chemotherapy drug doxorubicin, with or without 4-hydroxytamoxifen (4HT).

RESULTS

DMBA and cyclophosphamide decreased the number of primordial and total follicles, and this reduction was prevented by tamoxifen. Cyclophosphamide tended to reduce fertility and lessened neonatal survival. Tamoxifen reversed these defects. Doxorubicin caused oocyte fragmentation which was prevented by 4HT.

CONCLUSIONS

tamoxifen decreases follicle loss and improves reproductive function following exposure to ovarian toxicants including chemotherapy drugs in the female rat.

[Oncofertility: a new focus in women health-care...]

Although treatment and survival are the primary focus of health-care patients, with cancer survivors living longer it is now appropriate to consider their quality of life after treatment, including the possibility of becoming parents. There are several options for fertility preservation in cancer patients. Even though most of them are still experimental and their efficacy and reliability have not been determined, especially in women. The most successful alternative for female survivors is embryo cryopreservation, an approach not suitable for many single or virgin women or even possible for prepubertal girls. Reports of live birth after transplantation of human ovarian tissue have reinforced the clinical potential of ovarian tissue banking for fertility preservation. Many exciting studies are underway to improve the efficacy and solve the problems with current fertility preservation strategies, especially for in vitro culture of cryopreserved tissue or follicles. Continuous efforts to improve current strategies and to develop new strategies will benefit many women and children who are facing premature ovarian failure and sterility.

Optimizing potential for fertility: fertility preservation considerations for the pediatric endocrinologist

Whether for the prepubertal or pubertal child, the goal of fertility preservation is to obtain cells or tissues to be used to produce future children. For the prepubertal child, preservation efforts involve germ cells, earlier forms of sperm, and immature follicles, rather than mature spermatozoa or follicles. Options for prepubertal children include for boys freezing testicular tissue and extracting testicular sperm or for girls obtaining ovarian cortical or follicular tissue for storage. These procedures involve extraction and storage of immature gametes for subsequent in vitro maturation, although attempts for sperm currently involve only animal studies. For adolescent subjects who have sufficient gonadal development and reserve, sperm, oocytes, and ovarian cortex can be retrieved as among adults.

Ovarian stimulation for ovulation induction and in vitro fertilization in patients with systemic lupus erythematosus and antiphospholipid syndrome

OBJECTIVE

To review the current evidence regarding the relationship between systemic lupus erythematosus (SLE) and antiphospholipid syndrome and female infertility, as well as the risks associated with ovarian stimulation for ovulation induction and IVF. To establish, based on this information, guidelines for safe and successful assisted reproductive technology (ART).

DESIGN

A MEDLINE computer search was performed to identify relevant articles.

RESULT(S)

Systemic lupus erythematosus and antiphospholipid syndrome are not related to infertility, except for cases of amenorrhea accompanying severe flares, renal insufficiency-related hypofertility, and ovarian failure secondary to cyclophosphamide (CTX) therapy. The most threatening conditions in affected women undergoing ovarian stimulation are lupus flares and thrombosis, with the latter being especially associated with the occurrence of an overt ovarian hyperstimulation syndrome (OHSS). Friendly ovarian stimulation, single embryo transfer, avoidance of OHSS, administration of coadjuvant therapy, and use of natural E(2) or P through a nonoral route may constitute the safest approach. Systemic lupus manifested in acute flares, badly controlled arterial hypertension, pulmonary hypertension, advanced renal disease, severe valvulopathy or heart disease, and major previous thrombotic events are situations on which to discourage ART, especially due to the high risk of complications for both mother and fetus during pregnancy and puerperium.

CONCLUSION(S)

Ovarian stimulation for ovulation induction and IVF seems to be safe and successful in well-selected women with SLE and antiphospholipid syndrome.

Premature ovarian failure: etiology and possible prevention

Premature ovarian failure (POF) is defined as premature menopause in women younger than 40 years of age. This heterogeneous disorder (occurring in 1% of women younger than 40 of age and 0.1% of those younger than 30 years of age), is associated with many and different etiologies, such as chromosomal, genetic, enzymatic, iatrogenic, metabolic and infectious causes. Only in less than half of cases can the etiologic cause be identified. In the last decade, many genetic abnormalities were identified in association with POF, mainly owing to the transgenic mice models, which enabled the study of phenotype in these null mice. Iatrogenic POF after chemotherapy has gained worldwide interest owing to significantly improved survival in the last three decades and the ability to preserve future fertility and ovarian function in many young women who are survivors of young-age malignancy. The attempts of in vitro fertilization-assisted reproductive technology and embryo or unfertilized ova cryopreservation, combined with ovarian tissue cryopreservation and coadministration of gonadotrophin-releasing hormone agonists in parallel with chemotherapy may maximize future fertility and minimize long-term POF in these women.