Pregnancy and preconception
If you plan on starting a family in the near future then it may be time to start considering making some changes to your nutrition, lifestyle and fitness regime. Eating healthily and maintaining a good level of physical activity during the preconception stage is just as important as doing so when you are actually pregnant. A healthy diet and a good fitness in both partners may help to optimise male sperm quality and will ensure that the female body is prepared for a trouble free and happy pregnancy.
There are various factors which play a role in fertility whether directly of indirectly. Polycystic ovaries for example – are known to have a direct impact on fertility, whereas a condition such as an eating disorder may cause knock on effects that eventually could hinder conception.
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Body weight and conception
Being either overweight or underweight could reduce your chances of conceiving so it's important that you make every effort to achieve a healthy body weight before trying for a baby. Medical research has revealed that women who are obese with a body mass index (BMI) of over 30, stand an increased chance of experiencing complications during both pregnancy and birth, and in the first few days after the birth.
Bear in mind that it is equally important for both partners to be within a healthy weight range to maximise the chances of conception, so men who are hoping to become fathers should also make an effort to eat healthy foods and exercise regularly.
Ideally, both partners should aim to be within a healthy range with a BMI of between 18.5 and 25. If you are outside of this range then endeavour to gain or lose weight in a sensible fashion, meaning no crash dieting or eating junk foods as this will not do the body any favours.
For information about weight loss and weight gain and how a nutritionist may be able to help, please visit our weight management section.
There is a common misconception that mothers-to-be need to eat for two throughout all stages of pregnancy to provide both themselves and their growing baby with enough nutrients. However, this couldn't be further from the truth and mothers-to-be should ensure they are not eating too much as this could lead to excessive weight gain and an increased risk of high blood pressure, backache and cesarean birth because the baby is too large.
Experts instead recommend that pregnant women increase the amount of nutrients they eat, perhaps by changing their diet slightly to include more fruit and vegetables for instance. The average women should only need to consume approximately 300 extra calories per day for a healthy pregnancy and should by no means double what she usually eats.
With that said it is also essential that women don't gain too little weight during pregnancy, as again this can lead to complications such as low birth weight and premature birth among other risks.
Useful vitamins and minerals
During pregnancy women should try to ensure they are eating plenty of foods which are rich in calcium such as green vegetables, milk, yoghurt and other dairy. A diet rich in calcium (especially during the last ten weeks of pregnancy), will ensure your baby develops strong teeth and bones.
When a women is pregnant the body will begin producing a larger number of female hormones which will help the pregnancy to run smoothly. The problem with the extra hormones is that they tend to decrease and slow bowel and intestinal movements meaning that flushing out bodily waste becomes more difficult.
Eating lots of fibre will help to both prevent and remedy constipation whilst promoting normal bowel activity. Fibre can be found in fruit, vegetables, wholemeal bread, prunes/prune juice and cereals.
Folic acid is a B vitamin which plays a key role in the production and division of cells. It can be found in green leafy vegetables such as spinach and kale, fortified cereals and grains, orange juice and in supplements.
Ample medical research has shown that women who get 400 micrograms of folic acid per day both prior to conception and throughout early pregnancy will significantly reduce the risk of their baby being born with a neural tube defect (by up to 70 per cent).
A neural tube defect is a birth defect which involves incomplete development of the brain or spinal cord, of which spina bifida and anencephaly are among the most common.
Spina bifida is a condition in which the fetal spinal column is unable to close completely during the first month of pregnancy, damaging the developing spinal chord. Individuals with spina bifida will experience nerve damage, paralysis and muscle weakness in the nerve below the affected area of the spine, making it difficult to walk unassisted and often resulting in issues with bowel control.
Anencephaly is a more serious defect and prevents the development of the brain. Babies affected by anencephaly are either stillborn or die within a few hours of birth.
Medical experts are unsure as to why folic acid is so successful at preventing neural tube defects though it is known that the vitamin plays a vital role in the development of DNA, cell growth and tissue formation.
If you are pregnant or trying to conceive then as well as taking a supplement you should also be topping up levels of natural folate which can be found in baked beans, lentils, pea, soya beans, chick peas, leafy green vegetables and sprouts.
If you are epileptic, diabetic or have coeliac disease then you may require a higher dose of folic acid or may be on medication that will work against it. If this is the case then visit your GP before taking folic acid so they can advise you on the safest course of action.
Be aware that folic acid is quite easily lost in cooking so it is best to steam vegetables or boil in a little water to retain goodness. A qualified nutritionist will be able to tell you more about good sources of folate and how to best cook foods in order to retain heir health benefits.
Iodine is important for correct development of the baby's brain. Adults are advised to have 150 micrograms of iodine per day, and pregnant/breastfeeding women should get 200 micrograms per day. Having too much or too little can affect the production of thyroid hormones so it's important that you speak to a doctor about your requirements.
If you are struggling to meet your iodine requirements through diet alone, a supplement may be advised. Many (but not all) pregnancy multivitamins on the market contain iodine, so check this before getting additional supplements. A supplement should contain around 140-150 micrograms of your daily intake with your diet providing the rest.
Iron is an important mineral which is essential for the production of haemoglobin (the protein in red blood cells which carry oxygen around the body).
When a women falls pregnant the amount of blood in her body will increase by approximately 50 per cent to accommodate the baby, meaning that the body will need to produce more haemoglobin so that it can carry the additional blood.
Whilst pregnant, women should ensure their iron levels are topped up by eating plenty of lean meat, leafy green vegetables and nuts. If iron levels drop too low then this could result in iron-deficiency anaemia, a condition caused by a lack of red blood cells in the body which can cause fatigue.
Iron-deficiency anaemia is not uncommon in pregnant women due to the extra demand the body places on iron, vitamin and mineral stores during this time.
Some medical research has suggested that high doses of vitamin A can build up in the liver and cause harm to an unborn baby. In light of this the Department of Health are advising pregnant women to steer clear of foods containing a high vitamin A concentration and are warning expectant mothers to be aware that some fish liver oil supplements or other supplements are high in vitamin A.
Taking a supplement of at least 10 micrograms of vitamin D per day whilst pregnant will help to ensure your baby develops strong and healthy bones.
A small amount of vitamin D can also be obtained from natural sources such as certain foods and of course the sun, though the amount we procure from both is unlikely to fulfil the daily recommended amount which is why many women opt to take supplements.
If you were already eating a sensible and healthy diet containing all of the food groups before falling pregnant then you will need to make very few changes and can continue to eat what you were eating before becoming pregnant with very few exceptions. Generally you should try to make sure your eating regime includes lots of fruit and vegetables (five portions per day), plenty of reduced fat dairy products, protein such as lean meat, fish, eggs, pulses and beans, starchy carbohydrates such as bread, pasta, cereals and potatoes and lots of fluid. Pregnant women should ideally cut out alcohol entirely and should also steer clear of fatty and sugar heavy foods.
Foods to avoid during pregnancy
When pregnant there are certain foods that women should avoid or eat with caution in order to reduce the risk of food poisoning. These include:
Alcohol – Consumption of alcohol during pregnancy can cause harm to an unborn child, with some evidence suggesting that it is linked to an increased risk of birth defects and low birth weight. It may also prevent the mother from effectively absorbing all of the nutrients needed from certain foods.
Caffeine – Similarly to alcohol, caffeine can interfere with the body's ability to absorb important nutrients so mothers-to-be should try to limit their intake to no more than 200mg per day, (equivalent to approximately four cups of coffee or six cups of tea).
Cheese – Cheeses which are either veined such as blue cheese or stilton, or those which have a rind such as camembert or brie should be avoided. These cheeses contain a bacteria known as listeria which can be harmful to an unborn baby. Cheddar cheese, cheese spread, cottage cheese and processed cheese are all fine and do not carry any risks.
Eggs – Either raw or partially cooked eggs could put mothers-to-be at risk of salmonella so be sure to cook your eggs fully (solid egg and yolk). Homemade salad dressings and mayonnaise are things to look out for whilst eating out but the supermarket varieties usually only contain pasteurised egg and will therefor be safe to consume.
Fish – Pregnant women are encouraged to include fish in their diets as it provides lots of healthy vitamins and nutrients. However, there are certain fish which should be avoided as their high mercury content could affect the development of a baby's nervous system.
Though the amount consumed would have to be extremely high to pose a risk, it's best to limit tuna consumption and to avoid marlin, swordfish and shark. All other fish is fine to eat regularly but make sure it is cooked thoroughly.
Pate – Pate commonly contains listeria so is best avoided.
Raw or undercooked foods – Raw foods are a breeding ground for bacteria so during pregnancy it is best to thoroughly cook any meat, fish, shellfish etc as this will reduce the likelihood of food poisoning.
Common pregnancy problems
Coeliac disease and diabetes
If you are pregnant and have coeliac disease or diabetes then you may benefit from consulting a qualified nutritionist who will make sure you are eating a well balanced and healthy diet which is going to provide your baby with all of the nutrients it needs. If this service is not available on the NHS in your local area then there are plenty of independent nutritionists who can provide this service.
As mentioned previously constipation can become an issue for pregnant women due to the high volume of female hormones slowing movements in the bowel and intestines. To prevent discomfort eat lots of fibre and drink lots of fluids as this will ensure the bowel and intestines continue to function as normal.
Food cravings and aversions
A desire for specific foods may increase during pregnancy and some women may find themselves craving anything and everything from pickles through a cube of chocolate wrapped in parma ham. Experts are unsure as to what causes these cravings but they can certainly be weird and wonderful. Generally cravings are unlikely to cause any negative effects if the rest of the diet is healthy and balanced, though craving non food items such as washing powder, soap and charcoal etc (this is known as pica) is dangerous for both mother and child and advice should be sought from a medical professional.
Aversions are the opposite of food cravings, foods which you used to like but now find unappealing. Unfortunately some women find that it is specific healthy and nutritious foods which they can no longer tolerate so if this is the case then it is best to try substitutes such as a different fruit or veg, or you could try cooking them in a different form such as eating raw with dips or mixed into a dish.
Morning sickness is characterised by frequent sickness, nausea and vomiting which occurs predominantly during the first three months of pregnancy (though it does happen past this point for some women).
The severity of morning sickness will vary from person to person. Some may not suffer at all, some may feel a little sick in the morning and others may experience frequent nausea throughout the entire day.
The exact cause of morning sickness is unknown, though experts believe it is a combination of the hormonal changes and blood sugar imbalance.
If you are struggling to eat or keep food down then try eating small meals rich in carbohydrates every few hours, avoid eating fatty foods, steer clear of tea and coffee as these can worsen nausea and stick to foods which don't involve a lot of preparation (if you are having a good day you could prepare meals in advance and freeze them).
Vegetarians and vegans
Contrary to popular belief that a vegetarian or vegan diet could lead to development risks in an unborn child it is actually perfectly healthy to remain vegetarian or vegan throughout pregnancy so long as the diet is well planned and all food groups and vitamin and mineral requirements are met. If you are struggling to plan you diet, or are feeling weak during pregnancy then it it is advisable to get in touch with your GP or a qualified nutritionist for professional advice.
If you are 10 weeks pregnant, have a child under four years of age, or have a family income less than £16,190 then you may qualify for Healthy Start vouchers. These vouchers are distributed by the NHS and can be used to buy milk, infant formula and plain fresh and frozen fruit and vegetables from local shops and supermarkets. You can also get coupons which can be exchanged locally for free vitamins.
How can a nutritionist help me?
Conflicting and mixed messages from the media, family members and friends can often mean that pregnant women are left feeling confused about what they should be eating during pregnancy. If you are unsure or concerned about your diet then consulting a qualified nutritionist may help you to feel more at ease. A nutritionist will be able to assess your personal circumstances and current diet and will use this information in combination with the latest research to formulate a diet plan which is going to keep you healthy and give your baby the best possible start in life.
Having a good, well rounded and healthy diet has been linked to an increased chance of healthy birth weight, increased brain development and a reduction of some birth defects. In addition, the positive aspects of a healthy diet also cross over to the mother, having been linked to a reduction in morning sickness, fatigue, pre-eclampsia, mood swings, constipation and post-natal recovery.
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