Facts about Semen You’ll Be Glad You Knew

There are many facts about semen on the internet. Here is a summary of the most important as viewed by The Vasectomy Reversal Centre.

facts about semen1.Your Ejaculate Is Always A Mix

Every man’s semen consists of water, fructose, proteolytic, enzymes, potassium, lactic acid, magnesium, nitrogen, phospherous, sodium, vitamin B12, vitamin C, zinc and sperm. It is generally white or grey in colour and it’s role is to carry sperm up into the female. The semen is made from the testes, epididymes, seminal vesicles, prostate gland, bulboyrethral and urethral glands. Sperm make up around 5% in total of the amount of ejaculate and that is normal. Salts and sugars within the semen are there to provide energy to the sperm on their journey to find an egg. The colour is normally white or grey but occasionally, it can have a yellow colour. If there is a pink colour, this may be due to infection or recent surgery such as having a vasectomy reversal.


2. Normally, Not All Your Sperm Are Healthy

This is one of the extraordinary facts about semen. Some have two heads, two tails, strangely shaped tails, large heads, small heads. The World Health Organisation state that around 30% of healthy swimmers is considered normal and any more is a bonus of which 25% will be swimming forward. 25% are usually dead  and this is all totally normal. Sperm have three main parts to them: the head, mid piece and tail. Heads can be small, too large or double. Necks can be bent, the mid piece can be too big or too thin, and the tail can be bent, coiled, broken or double. These are all “normal” to be found in healthy semen ejaculate.


3. Sperm don’t always know where they are going

Ejaculation can travel some distance, the range of distance being between 2 and 10 inches. Within the semen, there will be a significant number of sperm that swim in circles, some that don’t swim at all and others moving around around very slowly. Approximately, 1 in 5 actually swim in the right direction after ejaculation. If 30% are swimming in a straight line, then all is well. They will always swim forwards, not necessarily in the right direction! To start, they know that heat is good and so they know that if they move towards the heat then they will be travelling further into the female.

In conjunction with this, at the time of ovulation, the female’s vagina becomes less acidic and the cervical mucus changes to a watery substance. Under a microscope, this mucus forms tiny channels, like swimming lanes, guiding the sperm forward. Although the exact mechanisms of how the sperm knows where the egg is are not fully understood, what is known is that the sperm can lie on the lining of vagina for days and when ovulation occurs, they suddenly all swim in the same direction.

Scientists are exploring whether there is some mechanism akin to the sense of smell that makes the sperm move. It is thought that the egg emits a chemical signal, a reaction called “chemotaxsis” that acts like a tracking system. However, scientists do know that when the sperm come into contact with progesterone in the female close to the egg, they want to swim only forwards, frantically, and their tail activity increases so that they can push into the egg’s membrane. The mechanism is brought about by cells in the sperm called catsper cells picking up the hormone signal from the progesterone.


4. Male Sperm Swim Faster Whereas Female Sperm Swim Stronger

Men produce male and female sperm. The female carries the X chromosome and the male carries the Y chromosome. An extraordinary fact about semen is that the speed at which they travel is very fast – 4-5 millimetres per minute! Seems slow but remember that they are averagely, 55 millionths of a millimetre in length. If you were to compare their size to a whale, then they would be travelling 15,000 miles an hour. That’s fast! Their journey is around 175 millimetres in total but in reality this journey can take between 10 hours and  3 days. Sperm carrying the male “Y” chromosome are reported to swim faster but die faster, sperm carrying the female “X” chromosome swim slower but live longer. Therefore there is an equal chance of having either sex of child.


5. Semen Changes Consistency

Semen “clots” very soon after ejaculation becoming very sticky, jelly-like in consistency. Between 5 and 40 minutes later, it will return to a liquid state again appearing runny and clear. This change of states is thought to be important for reproduction. This is all a normal process. After a vasectomy, semen consists of only the fluids and elements as above, there are no sperm. So after a vasectomy reversal, the only difference, is the new access of the sperm to the ejaculate. However, the consistency of semen can change with age, level of arousal, seasonal changes and stress so there are many variations of normal.

Unusually thick semen can be due to dehydration, which is temporary or really thick and clumpy could be connected with your testosterone levels. There are everyday fluctuations in semen consistency and only if the changes occur consistently for two to three weeks, should you be concerned. If you are trying to conceive, or have recently had a vasectomy reversal and have been advised to have frequent intercourse, then the frequency of ejaculation can change the consistency of the semen. The semen can be less in volume, and have a different appearance and consistency.


6. Too Much Heat Kills Them

Laptops, Hot-tubs, hot baths, saunas and underwear that is too tight can all increase the temperature of the testes and therefore kill the sperm. Tight fitting lycra and cycling can also have a detrimental effect.


7. Semen Smells of Chlorine

One of the strange facts about semen is that it does smell like chlorine. This is normal; there is actually a small amount of chlorine in semen. However, if it starts to smell really badly, then this could be a sign of infection and you should see your GP.


8. Sperm Live For Up To Five Days

This is in females, not elsewhere! So in essence, if a woman ovulates at any time during this five day period, then pregnancy could occur. Sperm do not live anywhere else for this period of time. Normally, they die within minutes.


9. Sperm Quality Can Always Be Improved. Some super foods that can change the quality of the sperm:

Oysters – expensive but high in zinc and selenium. Not many people of access these super foods so a supplement containing zinc and selenium would be very beneficial.

Bananas – rich in vitamin B

Walnuts – 12 weeks of eating 75g a day of walnuts may improve vitality, movement and overall health of sperm

Asparagus –  high in antioxidants but can make your urine stink.

Dark chocolate – a few small squares a day

Garlic – one to two cloves chopped or crushed and added to food daily will help improve sperm counts If these foods don’t appeal for whatever reason you can always look to our health sperm diet for more information and advice on supplements.


10. Lubricants May Cause More Harm Than Expected

A recent study in New York tested a variety of shop bought and home based lubricants. One of the most important facts about semen that you need to know is that semen are affected by lubricants. Of all those tested, baby oil was one of the home based oils that had no real negative impact on healthy donor sperm whereas some KY products showed a decline in sperm movement. So it may be better to focus on baby oil if you need a lubricant rather than any shop bought ones. Worrying about ejaculate is understandable but there is a lot going on and variation is totally normal.

If you have any questions, or would like to speak with us, please ring us on 0115 837 0300 during the day and 0800 559 3922 evenings and weekends.