SOUNDBITES The reasons for infertility are many and nutrition is no magic bullet. So- called fertility foods such as shark's fin, camel's hump or figs won't turn you into a baby-making machine, but if your diet isn't up to scratch, then you may find it more difficult to conceive, writes Paula Mee.
The sooner you start eating well, the more likely you are to get pregnant. A well- balanced diet containing plenty of fruits and vegetables, some dairy products, oily fish, lean meat, pulses, nuts and wholemeal bread and grains should supply you with all the nutrients to boost your chances of conceiving and having a healthy baby.
Being fertile is a matter of balance, especially when it comes to body weight. Being too thin or too heavy can interfere with ovulation. The connection between body weight and ovulation is estrogen. The ovaries produce estrogen and so do fat cells. If your body fat levels are too low, you will produce less estrogen. If your body fat levels are too high, you'll produce more. Either way, you can disrupt your reproductive cycle. Shedding a few pounds (or gaining a few if you're underweight) while you're trying to get pregnant is a good idea. Even a small weight loss can greatly increase your ability to conceive and have a healthy pregnancy.
Being fit and healthy is just as important for men who are hoping to conceive. There have been numerous research studies looking at pre-conceptual nutrition in men. Diets which are low in zinc can reduce sperm counts, while excessive alcohol intakes can reduce zinc levels even further. Zinc is found in foods such as seafood, nuts and cheese.
Selenium is essential for fertility and selenium deficiency leads to reduced fertility in all animal species studied. In a recent study of Scottish men, selenium supplements increased their sperm motility considerably. When the supplements were stopped, their sperm motility fell back to pre-treatment levels. While selenium isn't a cure-all for fertility, it's a good idea to include selenium-rich foods in your diet such as Brazil nuts, seafood, cereals and eggs instead of relying on a supplement.
Different forms of supplemental selenium have different levels of toxicity and too much of it may increase your risk of cancer. Low levels of other nutrients such as vitamins E and C also reduce fertility, but again it's better to eat nutrient-rich foods instead of taking supplements. Supplements are only a safeguard, not a substitute for a sound diet. And since regular over-the-counter multivitamins may contain mega doses of vitamins and minerals, they could be doing more harm than good. If you're eating well, the only supplement women need to take is a folic acid supplement. Taking folic acid prior to and in the very early stages of pregnancy can reduce the risk of neural tube defects (NTDs) such as spina bifida.
Current advice is that all women of child-bearing age who may become pregnant should take a supplement that provides 400ug per day of folic acid. This is in addition to folic acid rich foods in your diet, which should provide around 200ug per day.
Rich dietary sources include fortified breakfast cereals, fortified bread, green leafy vegetables (Brussels sprouts, broccoli, spinach and green beans), oranges, dried beans, peas and lentils.
For women, vitamins B6 and E influence hormonal balance and deficiencies can affect fertility. Phytoestrogens - compounds found naturally in some plants - mimic or block the action of the human hormone, oestrogen. Studies on animals have found that large amounts of phytoestrogens (found in soya foods), affect the development of their reproductive organs and fertility.
However, there is no evidence from the limited number of studies in humans that there would be similar effects on people.
Having said that, recent concerns have arisen about soya-based infant formula. Because they weigh much less, babies who drink soya-based infant formula are consuming higher levels of phytoestrogens than adults or older children who eat some soya products as part of a mixed diet.
There are concerns that this could adversely affect a baby's reproductive development. The advice from the UK's Food Standards Agency is that if you're giving your baby soya-based infant formula at the moment, you should talk to your GP or dietitian about changing to a different formula. In almost all cases, breastfeeding or another type of formula will be a better choice.
The research on whether or not caffeine can affect fertility is mixed. Experts generally agree that low to moderate caffeine consumption (less than 300mg a day) won't affect your fertility, but your doctor may recommend you cut it out entirely to lay it safe. Some 300mg per day is equivalent to four cups of instant coffee or about six cups of tea.
Regardless of whether good nutrition can help you get pregnant faster, there's little doubt that when you do conceive, sound nutrition is essential for your little bundle of joy.