Blood in the semen, which can be the sign of an infection or injury.
Semen is normally a whitish-gray color. It's usually quite thick after ejaculation, but liquefies within 30 minutes. Changes in the appearance of semen might be temporary and not a health concern. However, sometimes these changes can be a sign of an underlying medical condition that requires further evaluation Red or Brown Colored Semen If your semen is stained with a red or brown colored fluid it may be caused by blood. Sometimes a small blood vessel may burst when you ejaculate. Within a day or two the semen should return to its normal state, so there should be no need to worry. One possibility for the brown color is that it is due to blood which has been somehow mixed with the semen fluid before it comes out of the body. Normal semen should be white or near to thin or thick cream-colored fluid. Semen, also known as seminal fluid, is an organic fluid that may contain spermatozoa. It is secreted by the gonads (sexual glands) and other sexual organs of male or hermaphroditic animals and can fertilize female ova. During the process of ejaculation, sperm passes through the ejaculatory ducts and mixes with fluids from the seminal vesicles, the prostate, and the bulbourethral glands to form the semen. The seminal vesicles produce a yellowish viscous fluid rich in fructose and other substances that makes up about 70% of human semen. The discoloration in brown sperm or semen is caused by the presence of blood, a condition known as hematospermia. Brown sperm may be the result of overly-vigorous sexual intercourse. Men with prostate cancer may experience brown sperm. Semen is produced in the testes, which are contained in the scrotum. Semen (meaning seed in Latin), male ejaculate, or “cum, is a combination of seminal fluid and mature sperm (spermatozoa), which is ejaculated through the urethra during the male orgasm. Semen is the medium through which a male’s sperm is delivered to a female’s egg cell, or ovum, during procreative sex.  Pink, red, or brown sperm may mean that a man has blood in his semen, and this can be the sign of an infection or injury. Semen color can change from day to day, and a sudden change or a change accompanied by discomfort or a foul odor should be checked by a physician. When one refers to sperm color, he is usually referring to the color of semen. Usually, semen is white or grayish in color, due to the large amount of proteins present in the secretions. Yellow may also be a normal sperm color for some men. Report Abuse. Red or Brown Colored Semen If your semen is stained with a red or brown colored fluid it may well be blood. Sometimes a small blood vessel may burst when you ejaculate. Within a day or two the semen should return to its normal state so there should be no need to worry. If it continues then you should see your doctor Although doctors can't generally pinpoint the cause, brown semen is often caused by blood in the semen. It's usually harmless and it usually goes away on its own. If it lasts longer than a month, however, it's worth asking your doctor about it. It could be old blood from your kidneys or bladder or prostate. If you or your partner have brown semen, it is very likely that it is an infection and thus can definitely affect the partner. 1 Causes of dark colored sperm can be blood or infection. 2  Blood in the semen is called hematospermia. 3  It is due to the tear in the fragile blood vessels in which the semen passes, most commonly, the prostate. 4  Pus formation from the infection is also one of the causes of dark colored sperm. Causes of Dark Semen or Sperm. 1 
http://www.mayoclinic.org/discolored-semen/expert-answers/FAQ-20058363 https://answers.yahoo.com/question/index?qid=20080515142654AAt8Nrs https://en.wikipedia.org/wiki/Semen http://www.wisegeek.com/what-are-common-causes-of-brown-sperm.htm http://www.soc.ucsb.edu/sexinfo/article/semen http://www.wisegeek.com/what-factors-affect-sperm-color.htm https://answers.yahoo.com/question/index?qid=20061111175627AAKNIao http://www.answers.com/Q/What_causes_brown_semen_in_males http://www.tandurust.com/health-faq-2/dark-colored-sperm.html
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