Healthy eating for conception and pregnancy

How your weight affects your fertility

If you're very underweight, it can be more difficult to conceive. Being very overweight may also cause problems, especially if you also suffer from polycystic ovary syndrome. Being overweight and pregnant also increases the risk of complications during pregnancy, birth and in the few days after the birth.

The ideal weight range is usually calculated using the body mass index (BMI). A BMI of between 18.5 to 25 is a healthy weight for most people and associated with relatively low risks. For people with a BMI over 30, even a small weight loss can greatly increase your ability to conceive and have a healthy pregnancy.

So, take steps either to lose or gain weight in a sensible and sustainable way before you become pregnant. Crash dieting is not good for your health, and limiting your range of foods may mean you go short of important nutrients. If you're concerned about your weight, you may find it useful to speak to your doctor or practice nurse for further advice. They can refer you if necessary to a specialist dietitian.

What is a healthy diet during pregnancy?

With a few exceptions, you can continue to eat normally before and during pregnancy. A healthy diet includes regular meals and snacks, and a healthy eating regime contains:

• Plenty of starchy carbohydrates - bread, rice, pasta, breakfast cereals, chapattis, couscous and potatoes.
• Plenty of fruit and vegetables - at least five portions a day.
• Low or reduced fat dairy products such as milk, yoghurt, fromage frais and pasteurised cheeses.
• Lean sources of protein, such as meat, poultry, fish, eggs (well-cooked), beans and pulses.
• Not too many fat-rich and sugary foods.
• At least eight medium glasses of fluid each day.
• Very little or no alcohol.

he digestive system in pregnant women changes and becomes more efficient at absorbing certain nutrients. In fact, with only a few exceptions, most of the additional nutrient needs of pregnancy can be met by eating a well-balanced and varied diet. You don’t normally need to eat larger quantities of food.

Weight gain in pregnancy

Optimum weight gain in pregnancy depends on your pre-pregnancy weight. The baby and amniotic fluid are only a small part of the weight gain; the rest is an increase in the mother's fat stores which provide an energy reserve for later breastfeeding.

There are no specific recommendations for pregnancy weight gain in the UK.

Nutrients for pregnancy

Energy

Most of the extra calories needed in pregnancy are required in the last three months It’s estimated you need around 300 kcals extra each day. If you're less active during the last three months of pregnancy, this may mean you need very little extra food, because you’re not expending as much energy. If you continue to stay active, a snack of a couple of slices of toast with spread and a glass of milk or a yoghurt may be all you need.

Protein

Most people eat more than enough protein so there's no need to increase your protein intake. Try to follow healthy eating principles and include some lean meat, fish or poultry, dairy products, grains, nuts and pulses in your meals.

Fibre

It's particularly important to eat more fibre in pregnancy to avoid the common niggles of constipation and piles (haemorrhoids). Increase your fibre intake by eating fruit and vegetables, wholemeal bread and cereals, brown rice, wholemeal pasta and pulses. You should also drink more fluids because increasing fibre intake without enough liquid can make constipation worse.

Folic acid

Mothers who lack sufficient folic acid before conception and in early pregnancy are at increased risk of having a baby with a neural tube defect (NTD), such as spina bifida.

From the moment you start trying to conceive until the end of week 12 of your pregnancy, you should take a daily 400 microgram supplement of folic acid. Women with a history of NTDs should be prescribed a 5mg supplement.

These supplements should be in addition to dietary intake, which should be about 200 micrograms per day. You can boost your folic acid intake by choosing foods such as:

• Green leafy vegetables - cabbage, broccoli, spinach, Brussels sprouts, spring greens, kale, okra and fresh peas.
• Pulses - chickpeas, black-eyed beans and lentils
• Fortified breakfast cereals.
• Wholemeal and wholegrain breads and rolls or those fortified with folic acid.

Folic acid is easily lost during cooking, so steam vegetables or cook in only a little water for a short time to retain as much goodness as possible. Supermarkets and food manufacturers often identify good sources of folic acid with a special label. Look out for these next time you go shopping.

Iron

Your iron levels will be measured throughout pregnancy, and if they’re found to be low you'll be prescribed an iron supplement. Pregnant women should try to maintain a good iron intake from their diet to obtain the other nutrients in these foods.

Good sources of iron can be split into two categories: meat-based (haem) and plant-based (non-haem). The body doesn't absorb iron from non-meat foods as easily as it does from meat sources. However, you can enhance iron absorption by including a source of vitamin C with your meal. Tannins found in black tea reduce the absorption. So, it's better to have a glass of orange juice with your bowl of cereal in the morning rather than a cup of tea.

Vitamin A

Too much vitamin A can build up in the liver and harm an unborn baby. So, although liver and liver products, such as paté and liver sausage, are good sources of iron, their high concentrations of vitamin A have led the UK Department of Health to advise pregnant women and women trying to conceive to avoid liver and liver products.

Some vitamin supplements and fish liver oil supplements are high in vitamin A, so always choose a specially prepared pregnancy supplement if you take one.

Vitamin C

Eat plenty of vitamin C-rich foods to help you use iron effectivelyGood sources include citrus fruits (oranges, tangerines, grapefruit and lemons), blackcurrants, strawberries, kiwi fruit, peppers, tomatoes and green leafy vegetables. Aim to eat at least five portions of fruit and vegetables every day; a drink of fruit or vegetable juice counts as one portion.

Vitamin D

Vitamin D is essential for forming and maintaining healthy bones and teeth. It's found in only a few foods, including fortified margarines and reduced-fat spreads, some fortified breakfast cereals, oily fish and meat. A small amount can also be found in milk and eggs. The body also makes vitamin D when the skin is exposed to sunlight.

Current recommendations are that pregnant women should take a 10 microgram supplement of vitamin D every day. Pregnant and breastfeeding women with dark skin, or those who always cover their skin, are at particular risk of a vitamin D deficiency.

Calcium

Your needs for calcium double during pregnancy, and are particularly high during the last ten weeks when calcium is being laid down in your baby's bones. Your body adapts to absorb more calcium from foods eaten, so you don’t actually need to eat more of it in late pregnancy, as long as it's present in your diet anyway.

Continue to ensure your diet has milk and dairy foods such as cheese, yoghurt and fromage frais. Official advice is to have three servings every day – and typical servings include a glass of milk, milk with cereal, a small matchbox size chunk of hard cheese or a small pot of yoghurt (125g to 150g). Other sources of calcium include bread, green vegetables, canned fish with soft, edible bones (salmon, sardines and pilchards), dried apricots, sesame seeds, tofu, fortified orange juice and fortified soya milk.

Healthy start vouchers

If you're pregnant and on a low income, or claim income support, you're entitled to 'Healthy Start' vouchers to exchange for foods such as milk and fresh fruit and vegetables. You can also claim to get free vitamin supplements. Speak to your midwife or health visitor.

Food poisoning during pregnancy

Food poisoning can be dangerous to your unborn baby, especially in the case of listeriosis and toxoplasmosis.

If you follow the guidelines below, your risk of food poisoning will be low.

• Always wash your hands before preparing food.
• Keep kitchen surfaces, cooking utensils and tea towels scrupulously clean.
• Store cooked and ready-to-eat food in separate containers and shelves in the fridge; don't let juices from raw or thawing meat or fish drip on to other foods.
• Use separate chopping boards for preparing meat or poultry, and fruit and vegetables.
• Wash fruit and vegetables thoroughly to remove dirt and soil.
• Never eat food that has passed its use-by date.
• Cook food thoroughly and according to manufacturers' instructions.
• Cool leftover food quickly and use within 24 hours.
• Wash your hands carefully after touching any animals.
• Avoid cat litter trays - if you need to touch them, wear gloves.

Foods to avoid during pregnancy

In pregnancy, avoid the foods known to increase the risk of developing food poisoning. These include:

• Cheeses such as camembert, brie or others that have a similar soft rind. You should also avoid blue-veined cheeses such as stilton. All of these cheeses can contain listeria, a type of bacteria which can be harmful to your unborn baby. There's no risk associated with hard cheeses such as cheddar or with cottage cheese, processed cheese or cheese spread.
• Pâté can contain listeria so it's best to avoid all types.
• Raw or partially cooked eggs. Eggs can contain salmonella, which causes a type of food poisoning. Eat eggs that have been cooked thoroughly, so both the white and yolk is solid. Avoid eating foods that may contain raw eggs or partially-cooked eggs such as homemade mayonnaise, salad dressings and ice creams. Most shop-bought mayonnaise and other salad dressings contain pasteurised egg, which is fine.
• Raw or undercooked meat or fish. Eat well-cooked meat that's very hot all the way through and is no longer pink in colour.
• Some types of fish. Some fish contain mercury, which at high levels can affect the development of an unborn baby's nervous system. Avoid eating shark, swordfish and marlin, and limit how much tuna you eat to no more than two fresh tuna steaks a week or four cans (one can = 185g) of tuna a week to minimise the toxicity risk. You can eat all other types of fish, and you should as part of a healthy diet. Aim for at least two portions a week, one of which should be oily fish.
• Raw shellfish Avoid raw shellfish when you're pregnant, as it can sometimes contain bacteria and viruses that may cause food poisoning. Well-cooked shellfish is fine.
• Alcohol. Heavy drinking during pregnancy can harm an unborn child, and there's evidence that it's associated with birth defects and lower birth weight. Minimise your alcohol intake. The Royal College of Obstetricians and Gynaecologists says there's no evidence that a couple of units once or twice a week will harm a baby, but some women choose to give up alcohol altogether during pregnancy which reflects current Department of Health advice.
• Caffeine. Current recommendations suggest that pregnant women should have no more than 300mg of caffeine per day, which is equivalent to four cups of coffee, six cups of tea, or eight cans of cola.

Help with problems

Pregnancy sickness

Nausea and vomiting (especially in early pregnancy and not necessarily limited to the morning, though it’s often called ‘morning sickness) affects about 70 per cent of pregnant women, and can range from just feeling queasy to being unable to keep anything down. Most women find their sickness goes after about three months.

Cravings and aversions in pregnancy

Food cravings and aversions are common during pregnancy. They're unlikely to have a harmful affect, provided the overall diet is nutritionally balanced. The most common aversions are to alcohol, caffeinated drinks, fatty foods and meat.

Heartburn and constipation in pregnancy

Indigestion, heartburn and intestinal discomfort are common, especially later in pregnancy when the baby displaces or squashes your internal organs. Fortunately, they're usually temporary problems. It can help to have smaller, more frequent meals, and to avoid lying down within one to two hours of eating. Some indigestion remedies available from pharmacies are suitable for pregnant women - check with your pharmacist before you buy.

For constipation , make sure you eat fibre-rich foods like breakfast cereals, wholegrain bread and rolls, wholewheat pasta, brown rice, fruit and vegetables, nuts, seeds and pulses. It's important to keep your stools soft to avoid the possibility of haemmorhoids (piles). Gentle exercise also helps to keep your gut moving.

Vegetarians and vegan diets during pregnancy

A well-planned vegetarian should be sufficient for you and your baby in pregnancy. If you follow a vegan diet, speak to a registered dietitian to discuss the need for supplements.

Other special situations

If you're pregnant and have a condition which requires a special diet, such as diabetes or coeliac disease, ask to be referred to a registered dietitian, to make sure you can maintain a healthy diet despite restrictions.

Your partner's weight

Eating a healthy diet and being the right body weight can be important for men who are hoping to become dads, too. There have been many studies looking at specific nutrients such as zinc and selenium and male sperm quality, and it does appear that a good diet produces better sperm. The key messages for men are:

• Aim to be the right weight for your height by eating sensibly and exercising on a regular basis.
• Follow the principles of healthy eating. Eating a variety of foods will help ensure you have all the nutrients you need such as zinc and selenium – you can increase your intake of these with fresh fruit, vegetables and whole grains.
• Stick firmly within the alcohol limits. Don’t t exceed three to four units per day on a regular basis, preferably with some alcohol-free days each week. Alcohol interferes with the body’s ability to make the most of a healthy diet.