Nutrition before and during pregnancy

Eating a balanced diet, before and during pregnancy, helps ensure that your body receives all the nutrients in the right amounts to support a healthy pregnancy. Healthy eating can also help to reduce the risk of developing conditions that can affect pregnancy, such as high blood pressure, gestational diabetes and obesity.

It is important to consider nutrition and exercise before pregnancy or while planning for pregnancy. Adopting healthy food behaviours (include food choices recommended by Canada's Food Guide), engaging in regular exercise and taking a daily multivitamin supplement will support the health of both you and your growing baby. This is especially important during the first trimester (three months) when vital organs begin to develop (brain, heart and lungs). Speak with your health-care provider to choose the most appropriate prenatal multivitamin supplement for you.

Learning about good nutrition will benefit you and your baby through your pregnancy and have long-term benefits for your child as they grow up.

General healthy eating recommendations for people of childbearing age

Consuming a healthy diet involves choosing a variety of healthy foods each day including vegetables and fruit, whole grains and protein-rich foods.

Every day, choose a variety of:

• fruits and vegetables:
• dark leafy green vegetables (e.g., kale)
• orange-coloured vegetables (e.g., carrots or sweet potatoes)
• whole-grain products:
• oats, wild rice, whole-wheat pasta, etc.
• protein-rich foods:
• eggs
• fish and shellfish
• beans, peas and lentils
• lean meats or lean cuts of red meat
• lower-fat dairy products (e.g., milk and yogurt)
• fortified soy beverages, tofu, soybeans and other soy products

Try to eat less of:

• foods that are high in sugar and sugar-sweetened beverages
• foods that are high in sodium, such as processed meat

While you are pregnant and/or breastfeeding, your body will need extra nutrients and energy. To make sure that both you and your baby get enough nutrition, Health Canada recommends adding an extra snack or small meal each day during your second and third trimesters and while breastfeeding.

If you are pregnant and carrying more than one child, you will need even more calories and nutrients. Health Canada recommends adding an extra snack or small meal for each baby during the second and third trimesters.

Fluids

Keeping yourself hydrated while pregnant is important. You may find you are thirstier during this time as your body produces greater volumes of blood to support your baby. Drinking water can help you stay cool, control swelling, prevent constipation and deliver nutrients from your body to your baby. Other healthy beverage options include pasteurized milk (e.g., cow’s milk or goat’s milk) and unsweetened fortified plant-based beverages. Eating juicy fruit can also be a great way to stay hydrated.

Key nutrients for pregnancy

Calcium and vitamin D

Your developing baby will need calcium to grow strong bones and teeth, a healthy heart, nerves and muscles.

The recommended calcium intake for people of childbearing age is 1000 mg/day. Continue to eat foods and beverages rich in calcium during pregnancy such as lower-fat milk, yogurt, cheese, calcium, fortified beverages, tofu, salmon or dairy-free calcium-fortified products. Some people may benefit from a calcium supplement in addition to a prenatal multivitamin. Speak with your health-care provider to determine if you need additional calcium supplementation.

Vitamin D helps the body utilize calcium, to support the bone health of both you and your baby. The recommended vitamin D intake for pregnancy is 600 IU/day. Many prenatal multivitamin supplements will include this amount of vitamin D.

Iron

Iron is important in forming enough healthy red blood cells to deliver oxygen throughout the body. Both you and your baby will need a rich source of iron during pregnancy. Iron requirements increase throughout pregnancy and peak in the third trimester. Not receiving enough iron during pregnancy can cause deficiencies and may lead to anemia, which can increase the risk for complications during pregnancy and childbirth.

To ensure a healthy intake of iron that meets your and your baby's needs, eat foods rich in iron, including:

• beans
• peas
• lentils
• tofu
• lean meats
• poultry
• fish
• eggs
• whole grain foods

Note: Animal sources of iron, such as beef, are better absorbed by the body over non-animal sources, such as vegetables or beans. To help your body absorb iron from non-animal sources, eat these foods with foods that are rich in vitamin C. For example, choose orange juice to drink when eating a lentil dish.

Note: Calcium supplements and calcium-rich foods can reduce the absorption of iron supplements and iron-rich foods. Do not take calcium supplements or have calcium-rich foods or beverages at the same time as iron supplements.

Health Canada recommends that pregnant people should take a prenatal multivitamin that has 16–20 mg of iron. Some people may need an additional low-dose iron supplement.

Folic acid

Folic acid, also known as folate, is a B vitamin that promotes healthy development of your baby's spine, brain and skull. Folic acid plays a key role in reducing your baby's risk for neural tube defects (defects that affect the brain and spinal cord, such as spina bifida), which develop during the first month of pregnancy.

To reduce the risk for neural tube defects, it is important to take folic acid before conceiving and throughout pregnancy.

• Start taking folic acid two to three months before becoming pregnant.
• Continue use until four to six weeks after giving birth, or until you are no longer breastfeeding.

If you did not take folic acid before becoming pregnant, start taking it as soon as you suspect you are pregnant.

Health Canada recommends taking a daily prenatal multivitamin supplement with 0.4–1.0 mg of folic acid. In addition to a multivitamin, focus on eating a well-balanced diet with folate-rich foods, including:

• dark green vegetables (e.g., broccoli, spinach, peas, brussels sprouts)
  
• corn
• lentils and other legumes
• oranges
  
• fortified products (e.g., enriched white wheat flour and grain products)
  

Note: The form of folic acid present in food is called folate.

Health Canada and the SOGC do not advise taking more than one multivitamin supplement a day. Taking too many daily supplements can lead to overconsumption of some vitamins and minerals, which may be more harmful than good. For example, taking too much vitamin A in retinol form (including retinyl palmitate and retinyl acetate) can lead to birth defects.

Speak to your health-care provider about finding the right prenatal multivitamin supplement for you.

Other important nutrients in pregnancy

• Protein: You will need more dietary protein during pregnancy. Protein plays an important role in supporting the growth and development of the placenta, uterus and breast tissue, and it helps increase your blood volume. Good sources of protein include meat, fish, eggs, milk products and plant sources such as tofu, beans and nuts.
• Iodine: Iodine is required to support the development of your baby’s brain and nervous system. Iodized salt is the most common source of iodine. Iodine-rich foods include dairy products and seafood.
• Vitamin C: Vitamin C supports the immune system, aids in growth and repair of tissues and helps the body absorb iron from iron supplements and plant-based foods. Include vitamin C–rich foods in your diet, such as citrus fruit, red peppers or tomatoes, and consume these foods with iron-rich animal foods, such as meat.
• Vitamin B12: Vitamin B12 helps to make healthy red blood cells and keep nerves working properly. Dairy and meat products are good sources of vitamin B12. If you follow a diet that does not include animal sources, include vitamin B12–fortified foods in your diet.
• Choline: Choline is an important nutrient during pregnancy, as it plays a crucial role in a baby’s brain development and the prevention of neural tube defects. Maternal choline intake requirements are higher than during non-pregnant periods. Choline-rich foods include egg yolk, dairy products, meat, fish and whole grains such as quinoa.

Fish and omega-3 fatty acids

Fish is an excellent source of protein, vitamin D, iron, selenium, zinc and omega-3 fatty acids. Omega-3 fatty acids are essential fats (fats that we can only get from our diet) that play an important role in the unborn baby’s growth and development.

Health Canada suggests that all people with female reproductive systems who are of childbearing age, particularly those who are pregnant or breastfeeding, pay special attention to the types of fish they eat. Some fish contain methyl mercury, a metal that builds up in the bloodstream over time and can damage an unborn baby’s nervous system. Though the body removes methyl mercury naturally, it can take a year for it to drop to safe levels.

Health Canada recommends eating at least 150 grams (5 oz.) of cooked fish (with low mercury) each week during pregnancy. The table below lists types of fish to include and avoid before and during pregnancy.

*These fish are all predatory (they hunt other fish), so they tend to accumulate methyl mercury from their diet as well as the surrounding water.

Caffeine

Health Canada recommends limiting caffeine to 200 to 300 mg a day. Consuming this amount of caffeine a day will not negatively affect fertility or a baby’s development. The effects of consuming more than 300 mg of caffeine a day are still unknown.

This table lists the typical caffeine content of common drinks.

Artificial sweeteners

Moderate use of some artificial sweeteners is safe during pregnancy. Other sweeteners, such as those in the table below, are considered unsafe and should be avoided.

Alcohol during pregnancy

The Society of Obstetricians and Gynaecologists of Canada (SOGC) recommends avoiding alcohol entirely during pregnancy. Consuming alcohol during pregnancy can cause negative outcomes to the baby, including fetal alcohol spectrum disorder. There is not enough evidence to confirm how much harm even small amounts may cause your baby.

Managing your weight during pregnancy

During pregnancy, it is important to gain a steady amount of weight by eating a balanced diet. Pregnancy is not a time to restrict food unless instructed by your health-care provider.

The amount of weight you should gain is based on your body mass index (BMI)* prior to pregnancy.

Health Canada and the Institute of Medicine recommend the following rates of weight gain during pregnancy.

*Your BMI is the ratio between your weight and your height. To calculate your BMI, divide your weight in kilograms (kg) by your height in metres squared (m²). For example, someone who is 5 feet 6 inches (1.676 meters) and 135 lb (61.4 kg) has a BMI of 21.8 → 61.4/(1.676 × 1.676) = 21.8.

Pregnant people who eat a nutritious, balanced diet and gain at least their recommended amount of weight can reduce the risk of having a baby who is premature and of a low birth weight. In contrast, excessive weight gain is linked to high birth weight, longer labour, birth trauma and caesarean section.

Exercise can also support a healthy pregnancy. According to the SOGC, everyone should do regular aerobic and strength exercises as part of a healthy lifestyle during pregnancy, unless there is a medical reason to avoid it.

Special considerations

Veganism

Many of the nutrients critical to a healthy pregnancy are found more readily in animal-based foods as opposed to plant-based foods. For this reason, special consideration must be taken to ensure adequate intake of nutrients such as vitamin B12, zinc, omega-3 fatty acids and iron.

Allergies and intolerances

If you have questions about how your personal dietary choices or allergies/intolerances may affect your nutritional intake during your pregnancy, consult your health-care provider.

Easing digestive discomfort through diet

Nausea and vomiting

Nausea and vomiting in pregnancy are thought to be linked to changing hormone levels; however, there is no one known cause. These symptoms affect more than half of all pregnant people.

Feeling unwell can lead to eating a less-varied diet, which can lead to poor nutritional intake. If you have nausea or vomiting in pregnancy, the following tips may help ease the symptoms:

• Do not skip meals and try to avoid having an empty stomach.
• Eat or drink small amounts frequently, every two to three hours.
• Try eating a piece of bread or dry crackers before getting up in the morning.
• Have a high-protein snack such as Greek yogurt, hard-boiled eggs or an apple with peanut butter before bedtime or during the night.
• Try carbohydrate-rich foods such as fruit, diluted fruit juice, breads and cereals.
• Try eating hydrating fruits, such as watermelon.
• Drink lots of fluids, such as water, slowly throughout the day.
• Try adding ginger to your diet.
• Avoid high-fat and fried foods.
• Avoid strong food smells and cooking odours.
• Avoid highly seasoned foods if these bother you.

People who experience severe vomiting during pregnancy, called hyperemesis gravidarum, are at risk for dehydration and weight loss. Call your health-care provider if you are experiencing frequent vomiting. You may need to be treated with medication and receive fluids through an intravenous (IV) line in hospital.

Heartburn

Heartburn can occur when the enlarged uterus presses up against the stomach, forcing stomach contents up the esophagus. It may also be caused by hormonal changes during pregnancy. While uncomfortable, heartburn only becomes a problem in pregnancy if it causes you to stop eating or become nauseous.

The following tips can help minimize heartburn:

• Eat small, frequent meals and snacks.
• Eat slowly and chew food well.
• Avoid spicy foods if they make your heartburn worse.
• Avoid citrus fruits or juices and carbonated beverages, such as pop.
• Avoid caffeine.
• Avoid lying down for one or two hours after eating.
• Avoid bending after eating.

If you experience heartburn, ask your pharmacist or health-care provider which antacid is safe during pregnancy.

Constipation

Constipation is another common concern during pregnancy. Constipation is linked to increasing hormone levels (progesterone) and can occur throughout all three trimesters. However, it is most common during the third trimester due to pressure from the growing uterus on the colon. Other contributing factors include not having enough fibre or fluids, limited physical activity and taking prenatal vitamins with higher iron levels than your body can process.

The following tips may help ease constipation:

• Increase fibre intake by eating more fibre-rich foods, such as whole-grain bread and pasta, beans and lentils, fruits, nuts, seeds and vegetables.
• Drink eight to 12 cups of fluid per day. Water is the best choice, but low-fat milk, decaffeinated tea and unsweetened juices are good alternatives.
• Aim for 20 to 30 minutes of moderate exercise, such as walking or swimming, three times per week to stay active.

If constipation is not improved with diet changes, ask your pharmacist or health-care provider which constipation remedies are safe during pregnancy.