 |
| Diet for pregnancy Plan |
Antenatal nutrition in women
Why is preconceptional nutrition important?A mother’s nutritional status prior to conception, (preconception 3 months before), and immediately afterwards, (periconception 2–3 months after), is critical. The fetus is most vulnerable to nutritional deficiencies in the first trimester of pregnancy, often before a woman realizes that she is pregnant.
There is evidence that poor maternal nutrition has both immediate (e.g. low birth weight) and long-term consequences. The so-called ‘fetal origins’ or ‘Barker’ hypothesis proposes that fetal growth plays a major role in determining the risk of some dietary related non-communicable disease, e.g. cardiovascular disease and type 2 diabetes in adulthood.
- Take folic acid supplements to protect against neural tube defects
(NTDs).
- To prevent first occurrence of NTD: 400 μg during preconception
and until the 12th week of pregnancy (on prescription or over the
counter).
- To prevent recurrence of NTD: 5000 μg during preconception and
until the 12th week of pregnancy (on prescription only).
- Foods rich in folic acid should be chosen .
READ ALSO -Allergy Overview and Diet Therapy | HUMAINOLOGY
Foods rich in folic acid
- Rich sources, >100 μg per serving: Brussels sprouts, kale, spinach
- Good sources, 50–100 μg per serving: fortified bread and breakfast
cereals, broccoli, cabbage, cauliflower, chickpeas, green beans,
iceberg, kidney, lettuce, peas, spring greens
- Moderate sources, 15–15 μg per serving: potatoes, most other
vegetables, most fruits, most nuts, brown rice, wholegrain pasta,
oats, bran, some breakfast cereals, cheese, yoghurt, milk, eggs,
salmon, beef, game.
- Eat a varied diet. The main points are:
- include 5 portions of fruit and vegetables a day;
- eat a variety of different foods from all food groups;
- restrict foods containing too much saturated fat and sugar.
- Achieve and maintain ideal weight at preconception
(BMI 18.5–24.9 kg/m2).
- Weight needs to be stabilized 3 months before attempting
conception.
- Low body fat content of <22% of body weight can prevent
ovulation (average body fat content of post-pubertal
women is 28%).
- Obesity (BMI ≥ 30) can inhibit ovulation due to associated changes
in insulin activity and its effect on hormone activity.
- Obesity at conception can influence the pregnancy (high blood
pressure, impaired blood sugar metabolism, gestational diabetes;
pre-eclampsia), delivery (preterm delivery; prolonged labour;
unplanned Caesarean), and infant’s health (stillborn fetus; difficulty
initiating and sustaining breastfeeding).
- Underweight (BMI <18.5) at conception can increase the risk of
pre-term delivery and of delivering a low-birth weight infant.
- Reduce alcohol consumption and ideally exclude alcohol.
- Alcohol intake may be associated with decreased fertility and can
affect the growing fetus.
- Binge drinking in particular is not recommended.
- Avoid excessive intake of retinol/vitamin A (B-carotene is not toxic).
- Avoid vitamin A supplements, liver, liver pâté, or sausage as retinol
is teratogenic at extreme intakes (8000–10000 μg).
- Avoid drugs that contain vitamin A or its analogues, such as cystic
acne medications (isotretinoin; treinoin).
- Women who smoke should seek support for giving up in preparation
for pregnancy.
- Women should be encouraged to follow the food safety advice for
pregnant women (see ‘Food safety in pregnancy and maternal weight
gain’, this chapter) as a precautionary measure for when conception
occurs.
pregnancy nutrition guidelines
Dietary recommendations are the same as for a normal healthy diet .Caffeine
May contribute to low birth weight by increasing fetal heart rate, although evidence is inconclusive. Tea, coffee, cocoa, and cola-type drinks are advised in moderation (<4 cups a day of these combined, equivalent to <300 mg/day). Suggest decaffeinated tea and coffee or other alternatives, such as fruit tea, fruit juice, or water. Tea and coffee also reduce iron absorption.
The following contain 7300 mg of caffeine:
- 3 mugs of instant or brewed coffee (100 mg each);
- 4 cups of instant coffee (75 mg each);
- 3 cups of brewed coffee (100 mg each);
- 6 cups of tea (50 mg each);
- 8 cans of cola (up to 40 mg each);
- 4 cans of ‘energy drink’ (up to 80 mg each);
- 8 (50 g) bars of plain chocolate (up to 50 mg each). Caffeine in milk
chocolate is about half that of plain chocolate.
Alcohol
Current optimal advice is abstinence in pregnancy, especially important in the first trimester; however, occasional drinking of small quantities, i.e. ≤4 units/week but no more than 2 units at any ‘sitting’ is unlikely to harm the fetus. Excessive binge drinking is most dangerous and can have teratogenic effects leading to fetal alcohol syndrome which affects 1–2/1000 births/year. Risk is elevated in women drinking >8 units/day. Symptoms in the infant are growth retardation, craniofacial and CNS defects, cardiac and genitourinary abnormalities.
Use of vitamin and mineral supplements in pregnancy
Women should try and obtain nutrients from a balanced diet and women need to be advised against taking high dose multivitamin and mineral supplements, some of which can quickly reach toxic levels and may have teratogenic effects (particularly vitamin A). Women should not consume more than 3300 μg/day (UK DH) of vitamin A and supplements are discouraged. However, in areas of the world where vitamin A deficiency is prevalent, supplementation may be beneficial for pregnant women.
Folic acid (400 μg/day) is the only supplement recommended for ‘blanket’ use by women until the 12th week of pregnancy. In the UK, iron supplements are advised only if there is evidence of
iron deficiency anaemia . Iron stores should be verified preconceptionally and in pregnancy. Iron supplements can cause constipation and other GI changes and may interfere with zinc absorption.
There is inconclusive evidence to recommend vitamin D supplements during pregnancy and currently the D.H recommends that sunlight and dietary sources of vitamin D should be encouraged to meet the increase in requirement of 10 μg/day and that only those on a restricted diet need extra vitamin D. Some Asian women could be at risk of vitamin D deficiency if insufficient skin exposure neonatal hypocalcaemia and rickets. ∴ may need vitamin D supplements. However this is controversial and the FSA now advises that a supplement of 10 μg of vitamin D should be taken during pregnancy and whilst breastfeeding. Advise caution about herbal supplements, as these are not generally evaluated for safety in pregnancy.
READ ALSO-PILES : DEFINITION , CLASSIFICATION , CLINICAL FEATURES , INVESTIGATIONS & COMPLICATIONS
foods to eat when pregnant
Besides following normal safe food hygiene practices, pregnant women should be advised to avoid additional practices that have been specifically linked to micro-organisms that can lead to fetal malformations.- Avoiding salmonellosis. In severe cases can cause premature labour
and miscarriage.
- Avoid raw or undercooked eggs due to salmonella risk. White
and yolk should be hard boiled. Raw egg may be found in homemade
mayonnaise, ice-cream, mousse,
- Avoid raw or partially cooked meat, especially poultry.
- Avoiding listeriosis. Caused by Listeria monocytogenes. Rare, but even
mild infection can lead to miscarriage, still birth, or ill newborn.
Women should avoid:
- all types of pâté (including vegetable);
- mould ripened soft cheese, e.g. brie, camembert;
- blue veined cheese, e.g. stilton, roquefort, and other
unpasteurized cheese;
- unpasteurized milk, including cow, goat, and sheep’s, and
associated milk products;
- eating uncooked or undercooked ready-prepared meals.
- Avoiding toxoplasmosis (mother has flu symptoms and infant has
blindness and mental retardation) caused by Toxoplasma gondii.
- Avoid cats as they can be carriers.
- Cook poultry and meat thoroughly.
- Wash salads, fruit, and vegetables to remove all soil.
- Reheat ready prepared meals and leftovers to avoid listeria.
- Avoiding vitamin toxicity.
- Avoid liver and its products, as they are rich in vitamin A.
- Reducing likelihood of developing infant allergies. Nut and peanut
allergy is increasing in UK. If there is atopic family history, women
should avoid:
- peanuts, nuts, peanut butter, and unrefined groundnut oil;
- foods containing nuts. Not always easy to follow; patients need to
check for ‘nut free’ label on foods.
- Avoiding mercury poisoning (can affect neural development of fetus).
- Avoid fish high in mercury: shark, marlin, and swordfish.
- Limit tuna to ≤4 medium size cans or 2 fresh tuna steaks a week.
Maternal weight gain
How much weight should a woman gain during pregnancy?It is not always easy to determine women’s energy requirements in early pregnancy as BMR falls in some women and rises in others. Weight gained in pregnancy is a combination of maternal and fetal tissues and fluid, as well as maternal fat stores. Rate of weight gain is usually not constant; around 2 kg (5 lbs) are gained in the first trimester and the remainder fairly evenly throughout the second and third trimesters at a rate of around 0.4 kg (1 lb) per week. An average weight gain of 10–12.5 kg (20–28 lbs) should be anticipated in women of normal BMI in higher income countries. Women who are
overweight or obese should not attempt to lose weight during pregnancy but should limit weight gain to 7–11.5 kg (15–25 lbs). Both too little and too much weight gain can adversely affect the fetus.
- Too much maternal weight gain during pregnancy can l postpartum maternal obesity; possibility of caesarean; infant macrosomia; and i risk of gestational diabetes.
- Too little maternal weight gain can l Low birth weight baby with subsequent effects on long-term health . In the UK, the D.H made a blanket recommendation of an extra 200 kcal per day in the last trimester. However, the best advice is to encourage women to eat to appetite in pregnancy and monitor weight gain within the above ranges.
Weight gain with multiple pregnancy
Multiple births account for 1 in 6 of every births in the UK. Women carrying twins (or more!) will gain even more weight than women carrying one fetus. In the absence of other guidelines, the US Institute of Medicine (IOM) recommendations are used. They advise 16–20.5 kg (25–45 lbs) weight gain for women carrying twins, who begin the pregnancy with a normal weight.1 Women pregnant with triplets should probably aim for a gain of around a further 4.5 kg (10 lbs). A healthy weight gain is particularly important in multiple pregnancies as they carry a higher risk of premature birth and low birth weight.
pregnancy food to avoid
Food aversions and cravingsAversions are relatively common especially for tea, coffee, fried food, and eggs. Food cravings can be strong but depend on the individual. There are no nutritional implications as long as not craving and eating a lot of energy-dense foods that result in excessive weight gain.
Pica
Pica is the persistent craving for non-food substances, ranging from coal, clay, candles, matchboxes, to soil. Pica can be harmful if the item craved and eaten is toxic or eaten in large enough quantities to have an impact on nutritional status. Eating soil could carry the risk of toxoplasmosis . Evidence for a physiological basis of need is inconclusive. Pica is often associated with iron deficiency but it is uncertain whether iron deficiency causes pica or conversely whether pica causes iron deficiency via its proposed effect on iron absorption.
Pregnancy (alias morning) sickness
During the first trimester, 770% of women have pregnancy sickness (nausea and vomiting) as the woman adjusts to higher hormone levels, especially human chorionic gonadotrophin and high oestrogen levels. Although often referred to as ‘morning sickness’ vomiting can occur at any time of the day: it varies from slight nausea to frequent and severe vomiting. Most cases are mild, but it impacts on the pregnant woman’s sense of well-being and daily activities. Hyperemesis gravidarum is the most severe form and is defined as persistent nausea and vomiting leading to dehydration, ketonuria, electrolyte imbalance, and weight loss greater than 5% of pre-pregnancy weight.
Advise:
- Frequent small meals and snacks every 2 h, avoiding large meals.
- High CHO foods are best tolerated, e.g. toast, dry biscuits, crackers,
low sugar breakfast cereals.
- Avoid smells and foods that exacerbate nausea, e.g. high fat foods.
However, these foods will depend on each woman.
- Taking food and drinks separately can help d nausea in some women.
- Encourage plenty of fluid, especially as water and other sugar-free
fluids, as dehydration may occur in extreme cases. Recommend
at least 35 ml/kg body weight/daily; equivalent to 9 mugs of fluid in a
65 kg woman (1 mug = 250 ml).
- Taking time to rest and relax; take fresh air.
- Reassure women that most cases resolve spontaneously in the first
16–20 weeks of pregnancy.
- When symptoms are persistent, severe, and prevent daily activities,
drug treatment should be considered.
Constipation
35–40% of women suffer during pregnancy, as peristalsis is slower. Encouraging fresh and dried fruit and vegetables for pectins and wholemeal bread and breakfast cereals for cereal fibre will relieve symptoms and plenty of fluid, preferably as water, should be taken. Faecal bulking agents may help. Women may intentionally restrict their fluid intake to reduce frequency of micturition; this could be a factor in them becoming constipated.
Heartburn
Heartburn is common and 30–50% of pregnant women experience symptoms. This can occur at any stage of pregnancy, but usually in the 3rd trimester.
Suggest
- Small, frequent meals.
- Eat earlier in the evening and avoid late night meals.
- Chew food thoroughly and slowly.
- Take fluids between meals, not at mealtimes.
- Dairy foods may relieve symptoms.
- Avoid spicy and acidic foods that may irritate GI mucosa. Food
causing symptoms varies a lot in different women; examples include
chilli, vinegar, pepper, acidic fruit juices.
- Avoid foods that relax oesophageal muscles before bedtime, e.g.
chocolate, fatty foods, alcohol, and mint.
- Sleep propped up with cushions.
- Avoid bending after eating.
Iron deficiency anaemia
Women with diets poor in iron prior to pregnancy and a history of anaemia will need haemoglobin and ferritin status verifying to assess whether supplements are required. Anaemia is most likely to affect women on a low income , those with low BMI, or vegetarians with an unbalanced diet . In the
UK, iron supplements are advised only if there is evidence of iron deficiency anaemia. However, care should be taken not to ‘blanket’ prescribe iron supplements (can result in nausea and constipation), as in later pregnancy many women experience haemodilution and ∴ physiological changes may
resemble iron deficiency (dhaemoglobin and dferritin).
Gestational diabetes
Estimated prevalence is 3–5% of pregnancies. Abnormal glucose intolerance occurs in pregnancy and usually disappears after birth, although there is evidence that it is a marker for development of type 2 diabetes in later life. Diagnosis is made at fasting blood glucose >7 mmol/l. Women who are obese/overweight, aged ≥30 y, and have a family history of type 2 diabetes are at greater risk of developing gestational diabetes, increased risk of macrosomia at birth, and increased likelihood of Caesarean.
Vulnerable groups in pregnancy
Adolescents
Pregnancy in adolescence increases risk to:
- fetus of low birth weight, perinatal mortality, and premature delivery;
- mother of anaemia, difficult labour, and hypertension. As adolescents are still growing, optimal weight gain is unknown, but it is likely to be higher than for adult women . They are less likely to eat healthily and have higher RNIs for calcium and iron than women >18 y ∴ they are less likely to meet requirements for calcium and iron. Iron deficiency anaemia can result in low birth weight and preterm delivery. Social problems may have an influence and will compound pregnancy outcome, including:
- reducing energy intake to try and hide pregnancy;
- low income;
- smoking;
- alcohol consumption;
- substance abuse;
- previous dieting leading to low nutrient stores;
- less knowledge of a healthy diet.
The current UK government’s Teenage pregnancy strategy (2004) has set targets of halving the number of under 18 conceptions by 2010, and getting 60% of teenage parents back into education, training, or employment.
READ ALSO-ITCHING ANUS : DEFINITION , CAUSES , TREATMENT & PREVENTION
Vegetarians
Being vegetarian should pose no problem in pregnancy, if the woman is well informed and eating a balanced lacto-ovo and lacto-vegetarian diet. Pregnant vegan, fruitarian, and macrobiotic women should be seen by a dietitian to assess overall nutrient adequacy of their diets. They may require supplementation of vitamin B12, iron, vitamin D, or calcium (if <600 mg/day consumed). Some fortified soya milks contain these nutrients. Asian vegetarian women could be at risk of vitamin D deficiency if insufficient skin exposure neonatal hypocalcaemia and rickets ∴ may need Vitamin D supplements. Pregnant vegetarian adolescents are at particular risk of inadequate diet if they are the only ‘veggie’ in the house, as they may tend to eat the same as the rest of the family except ‘remove’ the protein aspect of the meal or replace it with cheese, ready prepared vegetarian sausages, and burgers.
Low income and pregnancy
Although it is difficult to generalize, UK women on low incomes may find it harder to achieve an adequate diet (see ‘Balance of good health and Key nutrients at risk of low intakes are: zinc and iron, and vitamins A, C, and E and essential fatty acids (EFAs) needed for fetal neural and vascular system development. EFAs are found in green vegetables, oily fish (e.g. tuna, sardines, mackerel,
salmon, herring, pilchards, trout, and kippers), and certain vegetable oils (e.g. corn, sunflower, and soya oils). Cheaper blended vegetable oils and margarine are often consumed but they contain less EFAs.
In the UK, the welfare food scheme has been replaced by the healthy start scheme. The healthy start scheme allows beneficiaries to exchange tokens for fresh fruit and vegetables through general retail .
Closely spaced pregnancies
Women having closely spaced pregnancies may have low nutrient stores at conception and in early pregnancy, so taking a dietary history would be useful to assess previous and current diet for nutrient adequacy (including iron status).
Need regular monitoring as there is an increased risk of gestational DM and HT; risk increases with BMI. During pregnancy there is an i risk of pre-eclampsia. At birth there is an i likelihood of caesarean section, post-operative complications, low apgar score, excessive birthweight of newborn (macrosomia), i perinatal mortaility (3 fold), and neural tube defects (NTDs) .
Diabetic women
Regular glucose monitoring and good compliance will result in the same outcome as for non-diabetic mothers. However, poor control can i risk of pre-eclampsia, i fetal problems, and i infant mortality.
0 Comments