title: Preserving fertility when choosing chemotherapy regimens - the role of gonadotropin-releasing hormone agonists.
abstract: BACKGROUND
  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.
  
  
  METHODS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Reproductive Endocrinology, Rambam Health Care Campus, Department Obstetrics and Gynecology, Technion - Israel Institute of Technology, The Rappaport Faculty of Medicine , 8 Ha'Aliyah St, Haifa, 31096 , Israel +972 4 7772577 ; +972 4 7773243 ; bzeev@techunix.technion.ac.il ; z_blumenfeld@rambam.health.gov.il.
authors.forename: Zeev
authors.initials: Z
authors.lastname: Blumenfeld
authors.forename: Ayelet
authors.initials: A
authors.lastname: Evron
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects*; D015925:Cryopreservation; D005260:Female; D005298:Fertility / Q000187:drug effects; D059247:Fertility Preservation / Q000379:methods*; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists* / Q000031:analogs & derivatives*; D006801:Humans; D016649:Primary Ovarian Insufficiency / Q000139:chemically induced / Q000517:prevention & control; D012189:Retrospective Studies
chemical_list: D007987:Gonadotropin-Releasing Hormone
keywords: fertility preservation; gonadotoxicity; gonadotropin-releasing hormone agonist; premature ovarian failure