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11 results

  • Are epigenetic mechanisms and nutrition effective in male and female infertility?

  • Kadriye Erdoğan, Nazlı Tunca Sanlier, Nevin Sanlier
  • Journal:
    Journal of Nutritional Science / Volume 12 / 2023
    Published online by Cambridge University Press:
    26 September 2023, e103
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  • This review discusses epigenetic mechanisms and the relationship of infertility in men and women in relation to parameters pertaining to nutrition. The prevalence of infertility worldwide is 8–12 %, and one out of every eight couples receives medical treatment. Epigenetic mechanisms, aging, environmental factors, dietary energy and nutrients and non-nutrient compounds; more or less energy intake, and methionine come into play in the occurrence of infertility. It also interacts with vitamins B12, D and B6, biotin, choline, selenium, zinc, folic acid, resveratrol, quercetin and similar factors. To understand the molecular mechanisms regulating the expression of genes that affect infertility, the environment, the role of genotype, age, health, nutrition and changes in the individual's epigenotype must first be considered. This will pave the way for the identification of the unknown causes of infertility. Insufficient or excessive intake of energy and certain macro and micronutrients may contribute to the occurrence of infertility as well. In addition, it is reported that 5–10 % of body weight loss, moderate physical activity and nutritional interventions for improvement in insulin sensitivity contribute to the development of fertility. Processes that pertain to epigenetics carry alterations which are inherited yet not encoded via the DNA sequence. Nutrition is believed to have an impact over the epigenetic mechanisms which are effective in the pathogenesis of several diseases like infertility. Epigenetic mechanisms of individuals with infertility are different from healthy individuals. Infertility is associated with epigenetic mechanisms, nutrients, bioactive components and numerous other factors.

  • Genetic risk factors in tumours of the testis: lessons from twin studies

  • Cornelis B Lambalk, Dorret I Boomsma
  • Journal:
    Twin Research / Volume 1 / Issue 3 / 01 June 1998
    Published online by Cambridge University Press:
    21 February 2012, pp. 154-155
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  • A threefold increase for testicular carcinoma has been reported in male dizygotic twins. In this comment we suggest the hypothesis that over-exposure to endogenously hypersecreted Follicle Stimulating Hormone (FSH) may underlie the pathogenesis. This is supported by several findings. 1) FSH hypersecretion in mothers of dizygotic twins is most likely an autosomal trait implicating the possibility of male offspring with the same hormone characteristic. 2) In testicular carcinoma higher levels of cyclin D2 are found. This is an FSH dependent stimulatory regulator of mitosis. 3) There is a marked similarity between geographical distribution in occurence of dizygotic twinning and testicular carcinoma. 4) Men undergoing surgery for testicular carcinoma have higher FSH concentrations and males with Down syndrome have higher FSH levels and are more at risk to develop testicular carcinoma. We suggest to study FSH secretion in males of familial dizygotic twins and furthermore the risk of developing testicular carcinoma in males with elevated FSH. These men with one testicle and/or with dysfunctioning Sertoli/Leydig cells.

  • Chapter 14 - The evidence-based practice of assisted reproduction

  • Edited by David K. Gardner, University of Melbourne, Botros R. M. B. Rizk, University of South Alabama, Tommaso Falcone
  • Book:
    Human Assisted Reproductive Technology
    Published online:
    16 May 2011
    Print publication:
    31 March 2011, pp 152-166

  • Summary

    Increased understanding of the intricacies of the follicular development and selection processes has been critical to the development of many of the new developments in ovarian stimulation in clinical practice. This chapter reviews these clinically related physiological aspects of ovarian stimulation, and discusses the resulting new concepts of ovarian stimulation. Recent studies have indicated that anti-Mullerian hormone (AMH) may be a more reliable and robust predictor of ovarian response during ovarian stimulation. The long ovarian stimulation protocol combining GnRH agonist with exogenous gonadotropin administration has been the most popular treatment regime for the past 20 years. The objectives of ovarian stimulation in assisted reproductive technology (ART) are evolving. A further development which promises to further reduce the burden of ovarian stimulation is the introduction of a long-acting follicle stimulating hormone (FSH) preparation which greatly reduces the number of injections required during an in vitro fertilization (IVF) treatment cycle.

  • Chapter 25 - Analysis of embryo-derived factors as markers of developmental potential and viability

  • Edited by David K. Gardner, University of Melbourne, Botros R. M. B. Rizk, University of South Alabama, Tommaso Falcone
  • Book:
    Human Assisted Reproductive Technology
    Published online:
    16 May 2011
    Print publication:
    31 March 2011, pp 278-288

  • Summary

    This chapter examines the process of in vitro maturation (IVM), its efficacy and safety, and explores why it is not more routinely used to treat infertility and what is required to make it a more viable clinical option. The treatment of infertility is based on in vitro fertilization (IVF) as the technology of choice. IVM is an alternative approach for generating mature oocytes that eliminates or significantly reduces the need for hormonal stimulation of the ovary. The benefit of IVM is that the procedure removes the need to administer large multiple doses of follicle stimulating hormone (FSH) normally used in conventional IVF treatment to women. Current IVM conditions compromise subsequent embryo development rates following fertilization. It is concluded that IVM, despite the reduced efficiencies of implantation potential and increased early miscarriage, should be viewed as having no risk of an adverse outcome to mother and child compared with conventional IVF.

  • Chapter 15 - Three-dimensional in vitro ovarian follicle culture

  • Edited by David K. Gardner, University of Melbourne, Botros R. M. B. Rizk, University of South Alabama, Tommaso Falcone
  • Book:
    Human Assisted Reproductive Technology
    Published online:
    16 May 2011
    Print publication:
    31 March 2011, pp 167-176

  • Summary

    The availability of gonadotropin releasing hormone (GnRH) antagonists did not only offer clinicians an alternative to GnRH agonists but, more importantly, has led to the development of new concepts aiming to increase safety and simplicity in ovarian stimulation. These include the modified natural cycle, mild in vitro fertilization (IVF), the use of GnRH agonist for triggering of final oocyte maturation with elective cryopreservation in patients at risk of developing ovarian hyperstimulation syndrome (OHSS), the administration of antagonists during the luteal phase for management of severe OHSS, as well as control of endogenous luteinizing hormone (LH) with GnRH antagonists in intrauterine insemination (IUI) cycles. Administration of GnRH antagonists can be performed by either a single dose or by using a daily scheme. The need to simplify ovarian stimulation led to the development of long-acting follicle stimulating hormone (FSH).

  • Chapter 29 - Ovarian tissue transplantation

  • from Section 7 - Ovarian cryopreservation and transplantation
  • Edited by Jacques Donnez, Université Catholique de Louvain, Belgium, S. Samuel Kim, University of Kansas
  • Book:
    Principles and Practice of Fertility Preservation
    Published online:
    04 February 2011
    Print publication:
    03 February 2011, pp 357-366

  • Summary

    The use of gonadotropin-releasing hormone agonists (GnRHa) for prevention of chemotherapy-induced gonadotoxicity remains controversial. With the initial dose of GnRHa, the pituitary gland releases endogenous gonadotropins. This initial follicle stimulating hormone (FSH) release stimulates the ovary. After continued GnRHa exposure, further FSH release is prevented. Gonadotropin-releasing hormone analogues can be administered in many formulations with different durations of action. The most common side effects of GnRH analogues are related to the subsequent estrogen deprivation. Vasomotor symptoms, hot flushes, night sweats, vaginal dryness and headaches can occur. Cotherapy of a GnRHa during chemotherapy has been under investigation since the mid 1990s. If prolonged GnRHa administration decreases ovarian blood flow, then less chemotherapy may reach the ovary. Direct effects of GnRHa or FSH on ovarian tissue may influence ovarian response to chemotherapy. For GnRHa to be of benefit to fertility preservation, they would likely need to spare both oocyte quantity and quality.

  • Chapter 20 - Fertility-saving surgery for cervical cancer

  • from Section 5 - Fertility preservation strategies in the female: medical/surgical
  • Edited by Jacques Donnez, Université Catholique de Louvain, Belgium, S. Samuel Kim, University of Kansas
  • Book:
    Principles and Practice of Fertility Preservation
    Published online:
    04 February 2011
    Print publication:
    03 February 2011, pp 257-265

  • Summary

    The follicle has a fundamental reproductive role in the ovary. Follicle growth takes 85 days in humans and most follicles become artistic at some stage with the oocyte continuing to play a critical role in follicular control and the regulation of oogenesis, ovulation rate and fecundity. The first primordial follicle in human foetuses is formed at 15-22 week gestation, at which point oocytes are enclosed by a single layer of pre-granulosa cells. Upon activation of primordial follicles, progression from the primary to secondary stage of follicular development requires further oocyte expansion, granulosa cell (GC) proliferation and investment of a luteinizing hormone (LH)-responsive theca cell layer. The pre-antral follicle continues its development and becomes increasingly follicle stimulating hormone (FSH) responsive. Follicular antrum formation and antral expansion are absolutely dependent on FSH. Luteinizing hormone appears to play a major role in mediating the final phase of follicular development.

  • Chapter 14 - Chorionic gonadotropin and luteinizing hormone supplementation during ovarian stimulation

  • from Section 4: - Non-conventional forms used during ovarian stimulation
  • Edited by Mohamed Aboulghar, Botros Rizk, University of South Alabama
  • Book:
    Ovarian Stimulation
    Published online:
    05 August 2011
    Print publication:
    23 December 2010, pp 151-161

  • Summary

    This chapter reviews the role of gonadotropin-releasing hormone (GnRH) antagonists in ovulation induction for in vitro fertilization (IVF). Although the purpose of the development of GnRH antagonists was originally a non-steroid contraceptive drug, it was found that GnRH antagonists have potential benefit in assisted reproduction. GnRH antagonists act by immediate suppression of pituitary gonadotropin release and rapid recovery of normal secretion of endogenous luteinizing hormone (LH) and follicle stimulating hormone (FSH). The inhibition of LH secretion is more pronounced than that of FSH, this being most likely due to the different forms of gonadotropin regulation and the prolonged FSH half-life, or the immunoactive and bioactive forms of FSH. The effect of oral contraceptive pills (OCP) for cycle scheduling prior to GnRH antagonist protocol on IVF cycle parameters and pregnancy outcome was studied. All OCP-pretreated cycles required significantly longer stimulation than non-pretreated cycles and higher total dosage of FSH.

  • Chapter12 - How to select ovarian stimulation protocols to avoid difficulties and complications

  • from Section 3: - Difficulties and complication of ovarian stimulation
  • Edited by Mohamed Aboulghar, Botros Rizk, University of South Alabama
  • Book:
    Ovarian Stimulation
    Published online:
    05 August 2011
    Print publication:
    23 December 2010, pp 130-142

  • Summary

    The aim of treatment with a gonadotropin-releasing hormone (GnRH) agonist is elimination of the luteinizing hormone (LH) surge and fluctuating LH concentrations, which compromise outcome in cycles of ovarian stimulation for in-vitro fertilization (IVF). This chapter addresses the characteristics of the standard long-course protocol. It is most common to initiate treatment in the luteal phase to minimize the consequences of the flare effect seen in the first few days of treatment with a GnRH agonist. The down-regulation effect of agonists can be established and maintained by multiple applications of nasal spray, single daily injection, or depo formulations lasting variable lengths of time. When the patient is down-regulated at the start of follicle stimulating hormone (FSH) treatment, subsequent follicular growth and recruitment is dictated by two elements: the ovarian reserve, which dictates the number of follicles available for recruitment, and the profile of circulating FSH concentrations.

  • 2 - Mechanisms of Follicular Development: The Role of Gonadotrophins

  • from PART I - PHYSIOLOGY OF REPRODUCTION
  • Edited by Botros R. M. B. Rizk, University of South Alabama, Juan A. Garcia-Velasco, Hassan N. Sallam, Antonis Makrigiannakis, University of Crete
  • Book:
    Infertility and Assisted Reproduction
    Published online:
    04 August 2010
    Print publication:
    15 September 2008, pp 10-24

  • Summary

    Folliculogenesis in women is a dynamic and uninterrupted process from fetal life until menopause. During follicle growth, the oocyte undergoes functional changes in order to become fertilizable at ovulation. However, various factors derived from the oocyte seem to play a crucial role for preantral follicle development. The growth of large antral follicles is depended on gonadotrophins. These hormones are obligatory for follicle maturation during the follicular phase of the cycle. Although follicle stimulating hormone (FSH) is important for follicle growth, steroidogenesis in the early follicular phase is the result of the cooperation of FSH and luteinizing hormone (LH) in the context of the two-cell two-gonadotrophin theory. The dual action of LH might have a potential application in IVF programs to control the number of follicles that develop during the exogenous administration of FSH, particularly in patients prone to excessive response of the ovaries, such as in polycystic ovary syndrome.

  • 13 - Controversial issues in assisted reproduction

    • By Caroline Overton, St. Michael's Hospital and the Bristol Royal Infirmary, Bristol, UK, Colin Davis, Fertility Unit, St Bart's and the London Hospitals, London, UK
  • Edited by Paul Serhal, Caroline Overton
  • Book:
    Good Clinical Practice in Assisted Reproduction
    Published online:
    22 October 2009
    Print publication:
    01 July 2004, pp 226-255

  • Summary

    Fibroids are a frequent finding in women with infertility. Gonadotrophin releasing hormone agonists (GnRH-agonist) will cause both uterine and fibroid shrinkage and a reduction or elimination of menstrual flow. Uterine artery embolization offers an alternative method of treatment that allows conservation of the uterus. Under local anaesthesia and sedation, an 18-gauge needle can deliver heat to a fibroid with localized ablation of a fibroid. Hysteroscopic myomectomy may be considered for women with submucous fibroids less than 3 cm. Uterine septum is the most common congenital abnormality of the female reproductive tract with an incidence of 2-3% in the general population. This chapter discusses hydrosalpinx, endometriosis and ovulation induction, endometriosis and intrauterine insemination, endometriosis and in vitro fertilization, and management of ovarian cyst. It also explains elevated follicle stimulating hormone (FSH), thin endometrium, assisted reproductive techniques, and embryo transfer.