Kitabı oku: «Need to Know Fertility, Conception and Pregnancy», sayfa 3

Spina bifida and hydrocephalus

In babies with spina bifida there is a defect in which part of one or more vertebrae (the bones making up the spine) fails to develop completely, leaving a portion of the nervous tissue in the spinal cord exposed, which leads to damage of the nerves. This defect can occur anywhere in the baby’s spine but is most commonly seen in the lower back. The condition varies in severity and much depends on where the defect is and how much of the nervous tissue is exposed. Mild cases may have no major disability but in more severe cases, there can be paralysis of the legs, loss of sensation and incontinence due to loss of bladder control.

Women who have had a child with spina bifida are more at risk than women who have had a child without the condition. In such instances, it would be worthwhile obtaining specific pre-pregnancy advice before conceiving again, and you should consult your doctor.

Hydrocephalus is where there is an excess of fluid in chambers within the brain. This often arises because the flow of fluid through these chambers is obstructed. The excess fluid builds up in the chambers and the pressure causes them to enlarge, which can damage the brain tissue. Hydrocephalus may occur with spina bifida or on its own.

Folic acid from supplements

The ideal time to start taking folic acid supplements is two to three months before starting trying to conceive. Make it a part of pre-pregnancy planning. The tablets can

must know

Folic acid allowance

• The recommended daily allowance for adults is 200mcg, but prior to becoming pregnant it is recommended that the intake is doubled to 400mcg a day.

• Continue to take 400mcg for at least the first 12 weeks of your pregnancy.

• Some doctors are happy for you to stop while others recommend you take it throughout pregnancy – folic acid is a vitamin that can help prevent health problems such as anaemia and might help to reduce any other pregnancy complications.

be obtained from all good pharmacies. If you don’t like taking tablets, try folic acid milk, also available from pharmacies; one carton usually represents the daily requirement. Always remember to follow the instructions on the pack carefully. If you are taking prescribed medicines, check with your doctor before taking any supplements to be on the safe side.

Folic acid from food

Folic acid is soluble in water and is stored mainly in the liver. It is largely destroyed by cooking, however, so serve salads and stir-fry or steam vegetables lightly rather than boiling them. You can obtain it from:

• fresh dark green vegetables like broccoli, Brussels sprouts, peas, green beans, chick peas and spinach

• oranges

• peanuts, although salted peanuts should be avoided if possible because of the extra salt. In addition, if you or your family has a history of peanut allergy or other allergic conditions, like asthma and hay fever, it is definitely recommended that you avoid peanuts during pregnancy

• many breakfast cereals have added folic acid (read the label) and milk and yoghurt also contain it

• wholemeal and wholegrain breads are high in folic acid, as are wheatgerm, brewer’s yeast and yeast extract, so add these to your diet

Many women with a healthy diet may already have a sufficient folic acid intake for pregnancy simply from their food without the need for supplementation. But folic acid deficiency commonly arises in pregnancy due to the many extra demands the development of the baby places on the mother’s body. Even women who have an adequate diet may not be taking in sufficient amounts of folic acid because the body is not absorbing it efficiently from food.

Folic acid supplements are therefore recommended for every woman trying to conceive to be sure that her intake is sufficient. In pregnancy, the kidneys filter folic acid from the blood at four times the normal rate, which is another reason why supplements are recommended. If you decide not to take folic acid supplements, however, ensure that you have a good daily intake of folic acid in your diet by eating suitable quantities of the foods listed on the previous page.

Foods to avoid

There are certain foods that are best avoided when you are trying to conceive and also in pregnancy. This is because of the risk of infection or because they contain potential toxins.

watch out!

When storing or preparing food, remember to keep raw meat and poultry separate from cooked or pre-prepared foods and use separate utensils for them. In addition, always wash your hands thoroughly after handling raw meat and poultry.

For example: unpasteurized milk, soft cheeses and pâté can contain a type of bacteria called listeria that can cause miscarriage and premature labour; raw and uncooked cured meats (such as ham and prosciutto) and unwashed (soil-covered) vegetables may carry toxoplasma, an organism that can cause abnormalities in the baby. Liver contains high quantities of vitamin A; and raw meat, poultry and eggs can carry salmonella, a type of bacteria that causes food poisoning.

Processed food

It is all too easy to rely on processed food from time to time when we have busy lives. But try if possible to avoid convenience foods that have been highly processed, such as canned foods and packet mixes. This is because these often have added sugar and salt as well as a high fat content. So if you have been taking care of what you eat and limiting salt and sugar intake, you might be unwittingly undoing the benefits of your efforts by eating processed pre-prepared food. These foods may also contain chemicals in the form of artificial flavourings, colourings and preservatives. The composition and additives in these foods can usually be identified by looking at the label.

must know

Foods to avoid eating in pregnancy

• unpasteurized milk and milk products such as soft and mould-ripened cheeses

• pâté

• raw and uncooked cured meat

• unwashed fruit, vegetables and salads

• raw or partially cooked eggs

• raw shellfish

• liver

• liver sausage

• dietary supplements rich in vitamin A, e.g. cod liver oil

• shark, swordfish, king mackerel

Fish

A US food and drug administration panel has recently recommended that pregnant women should limit their consumption of those fish that are at the top of the food chain. So you should not eat a lot of tuna, and completely avoid swordfish, shark, tilefish and king mackerel. This is because of concerns that these particular fish may contain levels of mercury that could be harmful to people, especially developing babies.

Mercury enters the sea environment through pollution and virtually all fish contain tiny amounts of mercury. Long-lived fish that are predators, such as sharks or swordfish, accumulate the greatest amounts of mercury in their bodies and so might be harmful to people who eat them regularly. The safe level of tuna intake with regard to the effects of mercury in pregnancy has not been established, but in the meantime it has been recommended that pregnant women should eat no more than two 175 g (6 oz) cans of tuna each week, just to be on the safe side.

Vegetarian and vegan diets

More and more people are turning to vegetarian or vegan diets. Some vegetarians eat dairy products and others eat dairy products but avoid eggs. Vegans avoid all animal products including meat, fish, dairy products, eggs and honey. Because a few micronutrients occur naturally only in animal products, planning a balanced vegetarian or vegan diet requires a little extra effort. There are not usually any problems with a well-balanced vegetarian diet before and during pregnancy, however. Such a diet provides sufficient protein, vitamins and minerals to meet the needs of most women, although sometimes iron supplements are required to help prevent anaemia caused by the extra demands of the unborn baby on the mother’s stores of iron.

Some very strict vegan diets contain no food at all that is derived from animal sources, including dairy products. Women following such a diet may need extra vitamin supplements and should discuss this with their GP. If you are a vegan, you may be prescribed supplements of calcium and vitamins D and B12. So there are not usually any problems with a well-balanced vegetarian diet during pregnancy; indeed, you will have some benefits, such as increased fibre in your diet from all the fruit and vegetables.

The quantity of food

How much food you need to eat depends on your body weight and BMI and also on how much exercise you take. However, if your BMI is in the healthy range for your age, typical servings per day of popular foods are as follows:

• one to two 75-110 g (3-4 oz) servings of lean meat

• six portions of fruit and vegetables, such as a medium-sized apple or peach or three heaped tablespoons of a vegetable

• five slices of wholemeal bread

• one to one and a half portions of rice (75 g (30 z)) or pasta (110 g (4 oz))

• one serving (medium bowl) of unsweetened breakfast cereal

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‘Eating for two’

Despite the old adage about eating for two during pregnancy, there is actually no need to substantially increase your food intake as your body becomes much more efficient in its use of food and energy when you are pregnant.

• 600 ml (1 pint) of milk or a 300 ml (½ pint) of milk and a yoghurt or serving (around 25 g (1 oz)) of cheese is enough to meet a pregnant woman’s extra calcium needs In addition, a portion (150 g (5 oz)) of fish can be eaten every other day

In late pregnancy, however, increase your energy intake by about 10 per cent, which amounts to an additional 200 calories for the average woman. This amount of calories can be gained by eating a large bowl of cornflakes with semi-skimmed milk, or two medium slices of wholemeal bread, very lightly buttered, although the amount can be spread out over several smaller meals if a large portion cannot be eaten in one sitting at this stage of pregnancy.

Dieting

Going on a diet to lose a lot of weight is not advisable or recommended immediately before or during pregnancy. This is because you may disturb your nutritional balance at crucial stages of your baby’s development. However, limiting weight gain in pregnancy is important for women who are overweight and this can be achieved by carbohydrate restriction, ensuring that you take no more than the recommended number of servings of carbohydrate in your daily diet.

Alcohol and caffeine

Every woman knows that excessive alcohol intake is harmful, especially in pregnancy, but few know just how much alcohol might be safe to consume. Similarly, we are increasingly conscious of our caffeine intake, with many of us now drinking decaffeinated beverages.

Alcohol consumption before pregnancy

Many women are unaware of the problems that excessive alcohol intake might cause for the developing baby, and few are aware that alcohol can reduce their fertility. Alcohol can upset the production of eggs from the ovary. A Danish study conducted in 1998 found that women drinking four or fewer units of alcohol a week were twice as likely to conceive than those drinking ten or more units a week. If your partner drinks heavily, this can affect his fertility, too, by upsetting the function of his testicles and their production of both the male hormone testosterone and sperm. However, moderate alcohol intake (up to three or four units a day) does not seem to cause male fertility problems.

The ideal is that you both give up alcohol while you are trying to conceive, or keep your alcohol intake very moderate as no one really knows what is the ‘safe’ level of alcohol. Remember, too, that if you are trying to get pregnant, you may not know that you have conceived until several weeks after

must know

Alcohol limits

• Generally, it is recommended that, to be on the safe side, you drink no more than two glasses of wine (or its equivalent in alcohol content) once or twice a week.

• Drinking more than 15 glasses of wine a week (or its equivalent) can be associated with a reduction in the baby’s birth weight.

• Drinking more than 20 glasses of wine a week can be associated with intellectual impairment in the baby.

conception, and continued alcohol intake at this point, especially if it is heavy, could harm your developing baby. If you frequently drink heavily and think that you will find it difficult to stop it is worthwhile obtaining specialist advice and counselling before attempting to get pregnant.

Alcohol consumption during pregnancy

During the first two months of pregnancy, the developing baby appears to be particularly vulnerable to the effects of alcohol and it is best to avoid alcohol completely at this time. In particular, avoid binge drinking, where you take a large amount of alcohol over a relatively short period, as the effects of this on the fetus are not yet clear. But if you are usually a light drinker and generally healthy, there appears to be very little chance that if you had too much to drink once early in your pregnancy that it will have harmed your baby.

The only way to be absolutely certain that alcohol does not affect your developing baby is to give it up altogether once you know that you are pregnant and throughout the rest of your pregnancy. Indeed, many women find that they lose the taste for alcohol in pregnancy. This may be the body’s natural way of avoiding a potentially toxic substance. However, if you do enjoy the occasional glass of wine, it’s worth knowing that there is no confirmed scientific evidence to prove conclusively that drinking under two glasses of wine a day during pregnancy causes a problem.

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Alcohol in pregnancy

• No one knows what the safe level of alcohol is in pregnancy.

• Drinking ten or more units a week can impair your fertility.

• Higher levels may also disturb the baby’s development.

• Very high levels can lead to fetal alcohol syndrome with physical abnormalities and intellectual impairments.

Fetal alcohol syndrome

There is no doubt that women who consume large amounts of alcohol in pregnancy can damage their developing baby and extremely high consumption of alcohol on a regular basis can lead to so-called ‘fetal alcohol syndrome’. This condition is rare, however, affecting between 1:300 and 1:2,000 pregnancies. The full syndrome affects only about a third of babies whose mothers drink around the equivalent of three bottles of wine a day in pregnancy. The fact that only a third of these babies are affected suggests that other factors such as poor nutrition, genetic make-up or drug abuse need to be present, in addition to heavy alcohol intake, for the syndrome to develop.

Fetal alcohol syndrome has several features: the baby is small; there may be abnormalities in the brain and nervous system that affect development and intellectual ability; there may also be physical abnormalities, such as a short, up-turned nose, receding forehead and chin and asymmetrical ears, causing a characteristic facial deformity.

Coffee consumption before pregnancy

There is no good and consistent evidence that establishes as fact the theory that drinking coffee reduces your fertility. The possibility of an effect has been raised, however, as it has been proposed that caffeine constricts the blood vessels and reduces the blood supply to parts of the body, including the ovaries and the womb, or because it interferes with the metabolism of the female hormone oestrogen.

Remember that caffeine is not only found in coffee. There is caffeine in tea and in some soft drinks like cola.

Coffee consumption during pregnancy

Caffeine crosses the placenta and blood levels in the developing baby are similar to those found in the mother’s blood. There is no good evidence to suggest that caffeine ingested in moderate amounts (up to four or five cups a day) harms the developing baby or causes problems, such as miscarriage or premature birth. However, large amounts of caffeine are not recommended in pregnancy as they might be associated with problems such as miscarriage, so you should avoid drinking more than five cups of coffee a day. Indeed, it is probably best to avoid taking that much caffeine even if you are not pregnant. Interestingly, many women go off coffee in the first few weeks of pregnancy. This might be the body’s own way of limiting caffeine exposure in your developing baby.

must know

Caffeine and smoking

Smoking is known to be linked to impaired growth of the developing baby. When a high caffeine intake is combined with smoking, however, this combination may have a more injurious effect on the baby’s growth than the effect of smoking on its own.

Smoking and drugs

Despite our awareness that smoking has a seriously adverse effect on our health, with particular concerns in pregnancy, many young women continue to smoke. They often think they will stop smoking when they conceive. However, smoking does not just affect the development of the baby, but also your ability to conceive successfully.

The effects of smoking
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• Smoking reduces male and female fertility.

• Smoking will reduce your baby’s growth.

• While it is best to stop smoking long before conception, stopping during pregnancy will make a difference to your baby and your health. It is never too late to stop.

Research has shown that smoking may triple your chances of not being able to conceive. If your partner smokes, he needs to give up as well. Smoking can damage his sperm as well as expose you to passive smoking. However, if you do stop smoking, your fertility returns to normal.

Smoking robs the body of vitamins, especially vitamins B and C, and can cause a build-up of free radicals in the body. Free radicals are molecules that can damage blood vessels, such as those supplying the placenta, thus reducing the supply of nutrients for the developing baby. So smoking is linked to having a small baby as it reduces the ability of the placenta to supply the baby with all the nutrients and oxygen it needs to develop to its full potential. In addition, if you stop smoking, you reduce the risk of certain bleeding problems from the placenta that can complicate the pregnancy and put both you and your baby at risk. Even after pregnancy it is important not to smoke around your baby. This is because the baby will be more prone to ‘cot death’ and to breathing problems.

All this means that it is important that you stop smoking before becoming pregnant. If your partner is also a smoker, it would be best if you gave up together so that you can support each other. Smoking is a powerful addiction and so it can be very difficult to stop. Your doctor can provide advice or support to help you come off cigarettes or refer you to a smoking cessation programme.

The effects of taking drugs
must know

Prescription drugs

Certain drugs or medicines can affect your chances of becoming pregnant and could go on to harm the baby in the womb. Equally, you may require medication for your own continued good health. If you take a prescribed medicine on a regular basis, be sure to discuss this with your doctor before you attempt to get pregnant.

When planning on getting pregnant or, indeed, if you are pregnant, you should not take street drugs. These are all potentially harmful to your baby. Some, like cocaine, can lead to birth abnormalities; others, such as heroin, methadone, amphetamines and marijuana, can affect the growth of your unborn baby so that it will be small. There is also an increased risk of premature delivery, bleeding from the placenta and an increased risk of infant death. The baby may also suffer from drug withdrawal symptoms after delivery as these drugs cross into the baby’s body while it is in the womb. The baby’s later development in childhood can also be impaired. In addition, there is a much higher rate of complications to the woman in pregnancy, such as anaemia, infections such as hepatitis and HIV and septicemia from infected needles, and thrombosis (blood clots).