When it comes to pregnancy, it can often seem like everyone is full of good intentions and advice – but with your nutritional needs changing, how do you know what to eat (and what to avoid) at every stage of the process? Accredited Practising Dietitian Debbie Iles investigates.
The nutrients you need
When you are preparing your body for pregnancy, optimal nutrition and body weight can have a positive effect on fertility. In fact, some nutrients, like folate, are important even before becoming pregnant.
Folate supplementation – which has been proven to reduce the incidence of neural tube defects – should ideally commence 2-3 months prior to conception. This is because neural tube closure occurs in the fourth week, which is often before a woman knows she is pregnant. Since bioavailability from food sources varies considerably, supplementation is always recommended before and during pregnancy.
Getting enough iron before falling pregnant is important, as women who are already iron-deficient prior to conceiving can find it very difficult to rebuild their iron stores once pregnant. Having good iron stores in the first trimester, more so than later in your pregnancy, may have the most impact in terms of a healthy pregnancy. Studies have shown that iron-deficiency anaemia has been linked to pre-term delivery and low-birth weight babies.
Zinc plays an important role in reproductive health for both men and women. Red meat, poultry and legumes all contain zinc, but oysters are by far the richest source – a good excuse to indulge!
Antioxidants are necessary for a healthy reproductive system. Brightly coloured fruits, vegetables and leafy greens are great sources of vitamins C and E, B vitamins and beta-carotene, as well as other micronutrients and antioxidants.
What to eat
When planning for a baby, the emphasis is on achieving and maintaining a healthy weight. Aim for a BMI between 18.5–25, or a waist to hip ratio (WHR) – your waist measurement divided by your hip measurement (in centimetres) – of 0.7. Being overweight or having a high WHR may reduce your chances of conceiving. On the other hand, being underweight can also adversely affect fertility.
There is also some evidence to suggest that the foods you eat could play a role in fertility. Harvard researchers followed nearly 18,000 healthy women for eight years to identify key elements that may increase chances of conception. Diets rich in mono- and polyunsaturated (‘healthy’) fats; plant-based proteins like nuts and legumes; wholegrains; low-GI carbohydrates and folate – all hallmarks of a healthy diet – may promote fertility. Trans-fats (found in commercially made chips, biscuits and other treats) are best avoided. Interestingly, the study also identified higher rates of conception in women who enjoyed full-fat dairy, rather than skim.
What to avoid
Smoking should be avoided and alcohol should be limited when trying to conceive. Some evidence suggests that as few as five standard drinks a week may impact on a woman’s fertility.
The jury is still out on whether caffeine avoidance is necessary, although a high intake may increase the risk of low-birthweight babies or miscarriage in some women. Consuming no more than 200mg caffeine a day (roughly two small coffees or 2–3 cups of tea) shouldn’t be a problem.
What about unplanned pregnancies?
It’s a good idea for all women of reproductive age to include folate in their diet, particularly since many pregnancies are unplanned. If your pregnancy is a surprise, rest assured that you may well be getting enough folate, since it can be found in many everyday foods – including all breads and many breakfast cereals.
Don’t be concerned that potentially low folate levels have harmed your baby. However, as soon as you find out you’re pregnant, see your doctor and begin pregnancy supplementation.
The nutrients you need
The requirements for most nutrients increase during pregnancy – with folate, zinc, iron, iodine and vitamin B6 especially important. Vitamin B12 supplementation may be required for vegan or vegetarian mums-to-be.
Supplementation is recommended throughout pregnancy, since requirements continue to remain high.
Requirements are highest in the third trimester, since this is when the baby acquires two-thirds of his or her zinc stores.
The RDI for iron is highest at this time, since maternal iron deficiency can increase the risk of pre-term deliveries and low-birth weight infants. Boost your iron absorption by eating vitamin C-rich foods in conjunction with iron (found in meat, fish and some plant-based sources), and avoid caffeine at mealtimes. Most pregnancy supplements contain some iron, although the amounts vary, so be sure to get your doctor’s advice before taking supplements.
This trace element is exceptionally important for pregnant women and growing children. Iodine deficiency in pregnancy increases the risk of damage to your child’s brain and central nervous system.
Marine foods and iodised salt can be valuable contributors – but increasing your salt intake is rarely recommended. Fortunately, Australian bread-making flours, including those used to make gluten-free bread, are now fortified with iodine (the exceptions are organic and some yeast-free breads). When choosing a pregnancy supplement, make sure iodine is included in the ingredient list.
Increased blood volume during pregnancy is the major reason vitamin B6 requirements are higher. Deficiency has been linked with pre-eclampsia or hypertension in pregnancy, excessive vomiting, and it may also impact on infant brain development. However, vitamin B6 is readily available in fortified breakfast cereals, vegetables, fruits and meats, so a balanced diet should easily ensure an adequate intake.
Amazingly, your calcium requirements don’t increase as the body absorbs calcium much better during pregnancy. However, many women don’t meet the RDI for calcium (3–4 serves dairy) so it won’t hurt to add more dairy to your diet.
What to eat
While pregnant women generally need to consume more of most vitamins and minerals, the same cannot necessarily be said of food – making the old ‘eating for two’ idea incorrect! Energy requirements vary significantly between women, depending on their level of activity, stage of pregnancy, body composition and pre-pregnancy BMI. However, most women only need an extra 1250kJ per day – even during the latter stages of pregnancy – which is no more than a banana and a small tub of yoghurt. Ask your doctor for advice on your specific energy needs during pregnancy.
Pregnant women are encouraged to eat 150g fish twice a week, but to avoid exposing your unborn child to excessive mercury, choose fish like sardines, salmon, herring and trout. They pack a mean omega-3 punch, but are low risk for mercury.
If you find you’re craving certain foods, there is usually no reason why you can’t indulge a little – but pregnancy isn’t an excuse to go overboard on treats! Contrary to popular belief, food cravings are not an indication of what your body needs. Choose nutrient-dense foods like fresh and dried fruit, nuts, frozen yoghurt and lean protein to counter the cravings. Limit foods containing empty calories, like soft drink, sweets and fried foods. Pregnancy is a time to make every mouthful count and nutrient-rich foods will benefit your baby, and keep you healthy.
What to avoid
Doctors recommend avoiding nicotine and alcohol during pregnancy as both substances can freely cross the placenta and harm your unborn child.
Caffeine should be limited to 200mg a day, as more than this has been found to increase the risk of miscarriage and low-birthweight babies.
Listeria infection (caused by food-borne bacteria) is also a concern for pregnant women. While it may only cause mild illness in the mother, it can result in miscarriage, stillbirth or a very ill premature baby. The good news is that high temperatures kill listeria. To avoid infection, fresh food should be stored below 4°C and cooked food should be heated to above 75°C before serving. For this reason, it’s best to avoid salad bars, soft cheeses, soft-serve ice-cream and cold meats while pregnant.
To cope with morning sickness
Eat small frequent meals throughout the day.
Avoid offensive odours and get some fresh air.
Take a break from cooking if you can and make sure household bins are emptied daily.
Drink enough fluids.
Eat high-carbohydrate snacks, like crackers, and sip on chilled drinks.
While a healthy diet is important, it’s more important to eat what you can keep down in the first few weeks. Be sure to take your pregnancy supplement each day. Take it with food and/or at a time when you feel less ill. If vomiting persists beyond 14 weeks, see your doctor.
The nutrients you need
Breastfeeding, while undoubtedly the gold standard of infant nutrition, doesn’t always come easily. If you are having difficulty, the Australian Breastfeeding Association has a 24-hour hotline (1800 686 268), or talk to a lactation consultant or your doctor.
While breastfeeding, certain nutrients, energy and fluids will be in high demand – much more so than during pregnancy.
Zinc requirements are highest during this phase, at 12mg/day.
Iron is one of the few nutrients for which requirements lessen after pregnancy, particularly in breastfeeding mothers. Most women don’t begin ovulating immediately if they are breastfeeding, which means you retain the iron that would normally be lost through menstruation. Unless you were anaemic during pregnancy, or lost a lot of blood and have been advised to take supplements, you should be able to get enough iron from your diet.
A new mother’s iodine requirements are almost double than normal, since breast milk needs to contain an adequate iodine content to support your infant’s growing brain. It’s possible to meet these iodine requirements with food, although an iodine-containing supplement is usually recommended. If in doubt, speak with your doctor about whether you need to boost your intake with supplementation.
What to eat
Exclusively breastfeeding an infant for the first six months uses a lot of energy – about an extra 2675kJ a day, in fact. For the second six months, about 2130kJ a day will be used in breast milk production. This is equivalent to 5–6 extra slices of bread a day.
You can keep your energy intake up with healthy, low-GI snacks, fruit and low-fat dairy foods. Choose nutrient-dense foods and aim for as much variety as possible, since there is evidence to suggest that food flavours do enter breast milk. This may make your baby more accepting of a wide variety of foods when they start eating solids.
Drinking enough water is also important for breastfeeding women, although it doesn’t increase milk production. A good guide is to drink a glass at each meal and again with each breastfeed.
What to avoid
Whatever the mother consumes is excreted in her breast milk. This applies to nicotine, caffeine, alcohol and other drugs. Care also needs to be taken with prescription and over-the-counter medications, so always advise the pharmacist if you are breastfeeding.
Alcohol is best avoided for at least 4–6 weeks after birth since breastfeeding can be unpredictably spaced at this time. It takes most women about two hours to clear one standard alcoholic drink from their bloodstream and their breast milk. Plan the occasional drink with this in mind, or express first if you expect to drink more.
A cup of coffee or tea is fine when breastfeeding. However, keep your intake moderate (no more than 200mg a day), as it takes babies a lot longer to clear the caffeine from their blood.
In general, there is no need to avoid any particular foods, spices or potential allergens when breastfeeding. A minority of infants may suffer a food allergy or intolerance in response to food compounds in the mother’s breast milk, but it’s important to remember that this is not the general rule. Addressing breastfeeding techniques should always be the first port of call with unsettled newborns, rather than food elimination. However, if your baby reacts strongly during or after breastfeeding, contact your doctor.
Additionally, no specific food has been shown to cause colic, so eat what you usually eat and aim for a wide variety of foods.
Losing the baby weight… sensibly
New mums have a tough enough job without having to worry about unrealistic weight-loss expectations. After the baby is born, most weight loss usually occurs in the first three months. After this, it typically begins to slow. It’s important not to embark on any drastic diets, especially in the first six months after birth. Your focus should be on eating a healthy, balanced diet. These tips should get you on track to your pre-baby shape:
Include low-GI carbohydrates at each meal and snack to keep your energy levels up and blood sugars stable. Grainy breads, legumes, sweet potato, fruit and low-fat yoghurt are all good options.
Plan healthy snacks rather than mindlessly picking at food. Prepare portions of dried fruit and nuts, keep small tubs of low-fat yoghurt on hand and keep plenty of fruit in the fruit bowl.
Try to cut out any midnight munchies – just because your baby needs a midnight feed doesn’t mean you do, too! Keep a bottle of water and an apple close by. If you are not hungry enough to eat that apple, then you certainly don’t need any bread, biscuits or chocolate!
Consider getting your fresh produce delivered. Having a big box of fresh fruit and vegetables arrive on your doorstep will help you cut back on unhealthy impulse buys, save you time and energy, and encourage healthy eating.
Keep portion sizes appropriate. A palm-sized portion of lean meat and a fist-sized portion of carbohydrate is a good guide for meals. There are no limits on salads and non-starchy vegetables, so go to town on these!
It is important to remember that it took nine months to gain the baby weight, and it will likely take at least that long to return to your previous shape. Whatever you do, avoid extreme kilojoule restriction and try to return to some light exercise as soon as you feel ready.
Should I take supplements?
In an ideal world, achieving optimal nutrition should be possible through diet alone – pregnant or not. However, pregnancy places exceptional demands on your body and it is not always possible for women to eat the right amounts of the right foods. To make life easier, there are many pregnancy-specific supplements on the market. Make sure you choose one that contains enough folate and iodine, and always read the label to ensure you are taking the right dosage. Be sure to seek your doctor’s advice on choosing the right supplementation for your needs.
Unless you have been given specific recommendations from your doctor following a blood test, it is not advisable to supplement with individual minerals like calcium, iron, or zinc as they tend to compete with each other for absorption and may cause a nutritional imbalance.
RDI for nutrients at different stages
Should I supplement?
Bread; fortified cereals and juice; green leafy vegetables; legumes; citrus fruit; berries
Yes. Start 2–3 months before you plan to conceive. Choose either a folate supplement or a tailored pregnancy supplement.
Bread; iodised salt; seafood; eggs and dairy (amounts vary)
Yes. Once pregnant, consider a tailored pregnancy supplement.
Red meat; fish; poultry; cereals; dairy; nuts; legumes
No, although most tailored pregnancy supplements will contain zinc.
Red meat; fish; poultry; wholegrain cereals; legumes; leafy greens
Not unless your doctor recommends it. Most pregnancy supplements contain iron regardless – check the label.
Meats; breakfast cereals; brightly coloured vegetables and fruit
No, although most tailored pregnancy supplements will contain B6.
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