eMedicine - Infertility, Male : Article by Jonathan Rubenstein, MD 04.11.03 08:05 (advertisement) Home | Specialties | CME | PDA | Contributor Recruitment | Patient Education November 4, 2003 Articles Images CME Patient Education Advanced Search Link to this site Back to: eMedicine Specialties > Medicine, Ob/Gyn, Psychiatry, and Surgery > Quick Find Urology Author Information Introduction Clinical Rate this Article Infertility, Male Differentials Email to a Colleague Workup Last Updated: July 23, 2002 Treatment Synonyms and related keywords: ejaculate volume, sperm concentration, Medication Follow-up oligospermia, too few sperm, low sperm count, azoospermia, no sperm in the Miscellaneous ejaculate, sperm motility, sperm morphology, gonad, testis, testes, testicles, Pictures fertilization Bibliography Click for related AUTHOR INFORMATION Section 1 of 11 images. Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Miscellaneous Pictures Bibliography Related Articles Adrenal Adenoma Author: Jonathan Rubenstein, MD, Staff Physician, Department of Urology, Northwestern University Medical School Adrenal Carcinoma Coauthor(s): Robert E Brannigan, MD, Assistant Professor, Department of C-11 Hydroxylase Urology, Northwestern Memorial Hospital Deficiency Jonathan Rubenstein, MD, is a member of the following medical societies: C-17 Hydroxylase American Urological Association Deficiency Cannabis Editor(s): Daniel B Rukstalis, MD, Chief, Associate Professor, Department of Compound Abuse Surgery, Division of Urology, Medical College of Pennsylvania-Hahnemann University; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, Chlamydial Pharmacy, eMedicine; Mark Jeffrey Noble, MD, Consulting Staff, Urologic Genitourinary Institute, Cleveland Clinic Foundation; J Stuart Wolf, Jr, MD, Director of Michigan Infections Center for Minimally Invasive Urology, Associate Professor, Department of Urology, University of Michigan Medical Center; and Stephen W Leslie, MD, Cryptorchidism FACS, Founder and Medical Director of the Lorain Kidney Stone Research Center, Clinical Assistant Professor, Department of Urology, Medical College of Follicle-Stimulating Hormone Ohio Abnormalities INTRODUCTION Section 2 of 11 Growth Hormone Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Miscellaneous Pictures Bibliography Deficiency Growth Hormone Background: Infertility is defined as the inability to achieve pregnancy after one Replacement in year of unprotected intercourse. An estimated 15% of couples meet this criterion Older Men http://www.emedicine.com/med/topic1167.htm Page 1 of 40 eMedicine - Infertility, Male : Article by Jonathan Rubenstein, MD 04.11.03 08:05 and are considered infertile. Historically, the workup for the infertile couple focused primarily on conditions of the female. Conditions of the male are estimated to Gynecomastia account for nearly 30% of cases of infertility, and conditions of both the female and the male account for another 20%. Conditions of the male that affect fertility are still Hematospermia underdiagnosed and undertreated. Hemochromatosis In general, causes of infertility in men can be explained by deficiencies in Infertility, Male ejaculate volume, sperm concentration (eg, oligospermia [too few sperm], azoospermia [no sperm in the ejaculate]), sperm motility, or sperm morphology. Intestinal Radiation This general division allows an appropriate workup of potential underlying causes Injury of infertility and helps define a course of action for treatment. The initial evaluation of the male patient should be rapid, noninvasive, and cost-effective. Nearly 70% of Kallmann Syndrome conditions causing infertility in men can be diagnosed by history, physical and Idiopathic examination, testicular volume estimation, and hormonal and semen analysis. A Hypogonadotropic rational approach is necessary to perform the appropriate workup and to choose Hypogonadism the best treatment options for the couple. Luteinizing Hormone Various treatments exist for the infertile couple, ranging from optimizing the current Deficiency semen parameters with medical therapy to minor surgical procedures and finally to complex sperm retrieval and assisted reproduction techniques. Technological Luteinizing Hormone-Releasing advancements in assisted reproduction make conceiving a child possible with as Hormone Deficiency little as one viable sperm and one egg. While the workup traditionally has been delayed until a couple has been unable to conceive for 12 months, beginning the Lymph Node workup at the first visit is now recommended because of a recent trend towards Dissection, delaying family planning. This article summarizes current knowledge of causes of Retroperitoneal infertility in men and describes its workup and treatment. Open Prostatectomy Pathophysiology: The physiology of normal spermatogenesis, ejaculation, and fertility must be understood prior to performing a thorough workup of the infertile Prostatitis, Bacterial man. This includes knowledge of the hypothalamic-pituitary-testicular system (ie, the integration system controlling sperm and testosterone production), the Scrotal Trauma embryology and physiology of the testis and accessory glands, and the process of fertilization. Sertoli-Cell-Only Syndrome Gonadal and sexual functions are mediated by the hypothalamic-pituitary-gonadal Spinal Malformation axis, a closed-loop system with feedback control from the testicles (see Image 1). The hypothalamus, the primary integration center, responds to a variety of signals Teratology and Drug from the CNS, pituitary, and testicles to secrete releasing factors, such as Use During gonadotropin releasing hormone (GnRH), to modulate pituitary function. Pregnancy Hypothalamic input from the CNS includes signals from the amygdala, hippocampus, and mesencephalon, which respond to various internal and external Testicular stimuli. Choriocarcinoma GnRH is released from the medial basal hypothalamus in a pulsatile pattern Testicular approximately every 70-90 minutes. It then travels down the portal system to the Seminoma anterior pituitary, where it stimulates the release of the gonadotropins, luteinizing Testicular Torsion hormone (LH), and follicle-stimulating hormone (FSH). The half-life of GnRH is 2-5 minutes. Its diurnal release may be due to melatonin from the pineal gland. GnRH Testicular Tumors: release is inhibited by negative feedback signals from the testicle, specifically Nonseminomatous testosterone and inhibin. Additionally, corticotropin-releasing hormone (CRH), released during stress, and opiates, both internal and external, down-regulate Tuberculosis GnRH secretion. The body responds to illness and stress by a decreased production of gonadotropins. Urethral Strictures http://www.emedicine.com/med/topic1167.htm Page 2 of 40 eMedicine - Infertility, Male : Article by Jonathan Rubenstein, MD 04.11.03 08:05 The pituitary gland, which lies on a stalk beneath the hypothalamus in the sella Urethral Trauma turcica, contains the gonadotropic cells that produce both FSH and LH. These are glycopeptides with a molecular weight of 10,000 daltons. They are made up of an Urethritis alpha chain that is identical with that of human chorionic gonadotropin (HCG) and thyroid-stimulating hormone (TSH) and a beta chain that is unique for each. FSH Urinary Tract has a lower plasma concentration and longer half-life than LH, and it has less Infection, Males obvious pulsatile changes. The pulsatile nature of GnRH is essential to normal Varicocele gonadotropin release; a continuous stimulation inhibits their secretion. This is clinically significant and is used in the medical treatment of prostate cancer and Vasovasostomy and endometriosis. Vasoepididymostomy After release into the systemic circulation, FSH and LH exert their effect by binding to plasma membrane receptors of the target cells. LH mainly functions to stimulate testosterone secretion from the Leydig cells of the testicle, while FSH stimulates Continuing Sertoli cells to facilitate germ cell differentiation. Gonadotropin release is Education modulated by a variety of other signals, such as estradiol (a potent inhibitor of both LH and FSH release), and inhibin from the Sertoli cell, which causes a selective CME available for decrease in FSH release. this topic. Click here to take this CME. The pituitary also secretes prolactin, which normally functions to stimulate breast development and lactation. Prolactin release is held in check by the hypothalamic Patient Education production of dopamine. The hypothalamus produces thyrotropin-releasing Click here for hormone (TRH) and vasoactive intestinal peptide (VIP). Both stimulate prolactin patient education. release. Men with elevated prolactin levels present with gynecomastia, diminished libido, erectile dysfunction, and, occasionally, galactorrhea. Prolactin inhibits the production of GnRH from the hypothalamus and LH and FSH from the pituitary. The testicle (Image 2), the end organ of the axis, contains the Leydig cells and the Sertoli cells, which respond to LH and FSH, respectively, by the secretion of testosterone (Leydig cells) and maturation of the germ cells (Sertoli cells). The testicles are derived embryologically from the genital ridge near the kidneys, and they descend to the scrotum during gestation. The intermesenteric nerves of the renal plexus innervate the testicle, and the blood supply is from the internal spermatic artery, the artery to the vas deferens, and
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