Scientists have made a breakthrough that could enable infertile men to father children with their own sperm.
Researchers at Muenster University in Germany grew mouse sperm in a laboratory and believe the same technique could be used with human sperm.
The landmark study was carried out using germ cells, which are found in the testicles and are responsible for sperm production in mammals. The cells were placed in a compound called agar jelly to emulate the environment of the testicles.
The same trial was then successfully replicated in Israel.
Stephen Gordon, a leading NHD male fertility consultant, said: "This is an amazing development that could revolutionise fertility treatment and allow every man to be a natural father.
"Infertile men naturally want to be the father of their child but at present have to accept that can't happen. With the mouse discovery, that could now be a possibility."
The findings were published in science journal, Nature.
Professor Mahmoud Huleihel of the research team said in a statement: "I believe it will eventually be possible to routinely grow human male sperm to order by extracting tissue containing germ cells from a man's testicle and stimulating sperm production in the laboratory."
The researchers have had no success applying the same tests to human cells as yet but they remain hopeful.
Professor Huleihel said: “We have already applied the same tests as we did with mice in the laboratory, using human cells, but as yet have not had success. We are confident that if it can be done in a mammal such as a mouse it can be done in humans.
“We are experimenting with a number of different compounds to get the germ cells to grow into sperm. And we believe it will be possible. And, hopefully, soon.”
He added: “‘It has taken us several years to reach this stage so a technique to create human sperm won't come overnight but we have started that research already after our success with mice.’”
Professor Huleihel’s team is about to start talks with Professor Richard Sharpe at Edinburgh University.
Professor Sharpe proposes using a live mouse as a host to make human sperm, it was reported in the Telegraph:
"What you would do is take some human testicular tissue with germ cells and place that under the skin of the mouse and use it to incubate the cells.
"You could then extract any sperm and use it in fertility treatment. But we would have to demonstrate that there were no mouse cells present in the extracted sperm if we were to use this technique and I believe that's possible."
A license would be required before lab-grown sperm could be used in fertility treatment but Professor Sharpe believes this hurdle could be overcome:
“The main thing that would have to be proved is that the sperm was not genetically damaged and was the same as sperm produced in the testes. Similar checks are already carried out on eggs and embryos used in women's fertility treatment.”
Male infertility has shown an increase over the last 50 years as sperm counts have decreased. A study in 2011 showed that eating too much junk food can make otherwise healthy men infertile while another study found that Wi-Fi laptops can also kill sperm.
Previous studies have shown that the following nutrients may help to boost male fertility:
Vitamin B12: According to Men's Health magazine, Japanese research from the Yamaguchi University School of Medicine found 42% of men taking a 1500mcg daily supplement showed improved in sperm count and motility.
Find it in… natural yoghurt, eggs, salmon, liver
Vitamin C: A study at the University of Texas found that vitamin C helps prevent sperm from clumping together and decreases abnormalities. Get your RDA of 1000mg from a diet rich in fruit and vegetables.
Find it in… raspberries, strawberries, oranges, asparagus, broccoli
Vitamin E: Tel Aviv University researchers found men who upped their intake by 200mg a day saw conception rates rise. Find it in… Muesli, porridge, sweet potato, avocado
Fatty acids: Fatty acids boost sperm's ability to penetrate the egg. According ton the Journal of Reproduction and Fertility, low levels of fatty acids are linked with sperm abnormalities.
Find it in… Oily fish, nuts, seeds
Zinc: A minimum daily intake of 15mg of zinc is necessary to not only boost sperm count but to increase its swimming stamina, too.
Find it in… Pumpkin and sesame seeds, eggs, red meat
For female fertility-boosting foods, see our tips below:
Although there is no direct link between refined carbohydrates and infertility, the refining process strips grains of some of the most important fertility-boosting nutrients, such as antioxidants, B vitamins and iron.
Modern methods of food production, involving intensive farming, rob the soil of vital nutrients, so where possible stick to organic produce. Processed foods are packed with additives and preservatives that can upset blood sugar levels and disrupt the body's hormonal balance.
Too much red meat increases the amount of ammonia in the body, which can interfere with the implantation of the egg in the uterus. Red meat can also be detrimental for men as it increases acidity and affects sperm activity; sperm perform better in alkaline conditions.
The animal hormones in dairy products can affect your own hormonal balance. If you balk at the richness of soya milk and can't bear to give up your semi-skimmed, switch to organic dairy products instead as these contain lower levels of hormones.
Giving up alcohol is not strictly necessary until you fall pregnant but it might be worth bearing in mind that Danish research, studying the link between alcohol consumption and fertility, found that alcohol intake had a significant effect on infertility success among women above the age of 30 who drank seven or more drinks a week.
While you don't need to give up your morning coffee, caffeine does constrict the blood vessels, slowing blood flow to the uterus and potentially making it harder for an egg to grab hold. So, if you're having any trouble conceiving, or undergoing IVF treatment, you might want to go easy on the double espressos.
Aside from being packed with vitamins and minerals, fruit and vegetables are packed with antioxidants that attack free-radicals (harmful molecules that can damage the ova, sperm and reproductive organs).
Zinc helps to maintain a healthy menstrual cycle as well as being vital during pregnancy to aid cell division in a developing foetus. Folic acid (Vitamin B6), together with zinc, is essential in the function of female sex hormones. Vitamin B12 is also very important as it maximises the absorption of folic acid. Taking a multi-vitamin tablet designed especially for conception is a good way to ensure you're getting enough of these valuable nutrients. Marmite is also a great source!