Vasectomy and vasovasostomy
Description
An in-depth report on vasectomy as a method of male birth control and reversal surgeries.
Introduction
In the United States, vasectomy emerged as a popular method of permanent contraception during the 1960s. Within a decade, 750,000 men were undergoing vasectomies each year. Vasectomy rates markedly declined in the 1990s and have now plateaued at about 500,000 a year. Worldwide, an estimated 42 million couples use vasectomy as a method of birth control.
The procedure works by surgically interrupting the route that the sperm take from the testicles (where they are produced) to the penis. After vasectomy, the testicles still continue to generate sperm, but their movement is blocked at the site of the vasectomy. Eventually the sperm die, and the patient's body absorbs them. During sex, semen is produced in the same amount as before vasectomy, but this fluid does not contain sperm.
>
Pathway of Sperm
Vasectomy should not be confused with castration. It has no noticeable impact on a man's ability to perform sexually, or on his sensation of orgasm and pleasure. It does not affect the balance of male hormones, male sex characteristics, or sex drive. Testosterone continues to be produced in the testes and delivered into the bloodstream. Sperm form a very small portion of semen, so patients notice no difference in the amount of semen produced during orgasm.
The Male Reproductive Tract
The male reproductive tract performs three functions:
-
It enables a man to produce offspring
-
It provides him with a supply of male hormones
-
It enables him to experience sexual pleasure
The Traveling Sperm
The sperm's journey through the male body -- from the testes (the testicles) to the final stage (the orgasm) -- is long and complex:
-
Sperm are produced in the testes at a rate of 50,000 an hour within tiny ducts called
seminiferous tubules.
-
Sperm do not mature in the testes. They must first pass into the
epididymis
, a C-shaped storage chamber adjoining the testes composed of a 20-foot coiled tube. The sperms' journey through the epididymis takes about 2 - 3 weeks. They are held here until sexual activity forces them to move on.
-
When a man experiences sexual excitement, nerves stimulate the muscles in the epididymis to contract. This forces the sperm to pass into one of two rigid and wire-like muscular channels, called the
vasa deferentia.
(A single channel is called a
vas deferens
. It is the vas deferens that is cut during vasectomy.)
-
Muscle contractions in the vas deferens from sexual activity propel the sperm along past the seminal vesicles, which are clusters of tissue that contribute fluid, called seminal fluid, to the sperm. The vas deferens also collects fluid from the nearby
prostate gland
. This mixture of various fluids and sperm is the semen.
-
Each vas deferens then joins together to form the
ejaculatory duct.
This duct, which now contains the sperm-containing semen, passes down through the
urethra
. (The urethra is the same channel in the penis through which a man urinates, but during orgasm, the prostate closes off the bladder so urine cannot enter the urethra.)
-
The semen is forced through the urethra during
ejaculation
, the final stage of orgasm when the sperm is literally thrown out of the penis.
|
-
Review Date: 10/20/2006
-
Reviewed By: Harvey Simon, M.D., Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital
|
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's
accreditation program
is the first of its kind, requiring compliance with 53 standards of quality and accountability, verified by independent audit. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s
editorial process
. A.D.A.M. is also a founding member of Hi-Ethics (www.hiethics.com) and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).
|
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997-2007
A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.