Weight Gain in Pregnancy

It is normal and healthy to gain weight during pregnancy. This weight includes your baby, your placenta, the fluid around your baby, breast growth, and some extra energy stores in your body (small amounts of fat). How much weight is appropriate to gain depends on your weight and height (body mass index or BMI) at the start of pregnancy. It is known that there are higher risks in pregnancy with a higher BMI pre-pregnancy or with excessive weight gain in pregnancy, which is why it is important to follow your weight gain during pregnancy.

BMI <18.5 (underweight) - gain 1lb (0.5kg) per week; total weight gain of 28-40lbs (12.5-18kg)

BMI 18.5-24 (normal weight) - gain 1lb (0.4kg) per week; total weight gain of 25-35lbs (11.5-16kg)

BMI 24-29.9 (overweight) - gain 0.6lb (0.3kg) per week; total weight gain of 15-25lbs (7-11.5kg)

BMI >30 (obesity) - gain 0.5 lb (0.2kg) per week; total weight gain of 11-20lbs (5-9kg)

Please note: the descriptions of the BMI categories above are from the World Health Organization classification. It is not meant to be a judgement on you, your health, or your weight.

To gain weight during your pregnancy, you will have different calorie requirements during different times of pregnancy. This is often not as many extra calories as you may expect. The extra calorie needs are different based on the pregnancy trimesters:

First trimester - no extra calories needed

Second trimester - 340 extra calories per day; 2-3 extra servings of food per day

Third trimester - 450 extra calories per day; 2-4 extra servings of food per day

Breastfeeding - 330-400 extra calories per day; 2-3 extra servings of food per day

These extra food servings are based on the Canada Food Guide recommendations. Whenever possible, choose nutrient-rich foods rather than processed foods or junk foods.

Nutrients and Vitamins in Pregnancy

Your baby and your body need certain nutrients to grow well and have a healthy pregnancy. Eating a healthy balanced diet rich in fruits and vegetables, with whole grains rather than processed grains, and protein is important to supply these nutrients. Even with a healthy diet, there are certain nutrients that need extra focus during pregnancy:

Folic Acid (Folate)

This nutrient is essential for the growth of your baby’s brain and nervous system. A lack of folate can lead to neural tube defects (see Genetic Screening in Pregnancy for more discussion on what this is). Folic acid is found in foods like beans/legumes, dark green vegetables, and fresh soy (edamame).

Every woman should supplement folic acid during pregnancy. Ideally, you should start this prior to pregnancy.

• Folic acid 0.4mg daily is recommended for most women - this is found in most prenatal vitamins

• Folic acid 1mg daily is recommended for women thought to be higher risk for neural tube defects:

  • History of neural tube defects in family

  • You have a history of a folate-sensitive anomaly (talk to your doctor about this if you or your children have had any birth anomalies)

  • You have a history of diabetes or obesity

  • You take an anti-seizure medication

  • You have struggled with alcohol use

• Folic acid 4mg daily is recommended for the first 12 weeks in women who have themselves had a neural tube defect or had a previous child with a neural tube defect

  • After 12 weeks, this can be reduced to 1mg

Iron

Iron is needed to produce and maintain red blood cells for you and your baby. It is also needed to support growth and development in your baby as well. During pregnancy, you need three times as much iron as you do when you are not pregnant.

Iron is found in many of the foods we eat, including:

• Animal protein (meat)

• Seafood

• Beans and legumes, including soy

• Dark green leafy vegetables

• Fortified and enriched grains (whole grain more than processed grains)

Most women cannot get enough iron from their diets alone during pregnancy. If you are not low in iron and just need to maintain your iron levels, your diet and the iron in your prenatal vitamin are likely enough. If you are low in iron (which is diagnosed on your lab work), you may need to take extra iron supplements.

• An extra 100-200mg elemental iron is needed if you are low in iron

• Different types/brands of iron pills have different amounts of elemental iron

• Iron supplements can cause constipation, but a few tips can help you absorb iron better and prevent constipation:

  • Take your iron supplement at least 1-2 hours away from any food or vitamin with calcium in it (this will include your prenatal vitamin)

  • Take your iron with vitamin C - this may be a glass of orange juice or a vitamin C tablet

  • Continue to drink plenty of water throughout the day

Choline

Choline is a lesser known nutrient that is important for development of the brain and nervous system and for preventing neural tube defects. It is not found in most supplements or prenatal vitamins. Choline is found in foods such as:

• Meat, poultry, seafood

• Eggs

• Whole grains

• Some low amounts in fruits, vegetables, dairy

Food Safety in Pregnancy

You may have heard of certain foods you should not eat in pregnancy, like sushi, raw eggs, or deli meats. The reason for this is because of changes to the immune system during pregnancy. These changes make pregnant women about 20-times more likely to develop a listeria, E. coli, or salmonella infection from certain foods, compared to non-pregnant women. An infection with these can lead to miscarriage, preterm labor, stillbirth, or serious disability.

Foods that you should avoid during pregnancy because of the risk of listeria, salmonella, or E. coli:

• Raw or undercooked meats, poulty or seafood (including raw sushi)

• Raw or undercooked eggs, raw egg whites (desserts like tiramisu, mousse)

• Deli meats, meat spreads, pate

• Soft, semi-soft, or blue cheeses

• Unpasteurized dairy or juices

Mercury

Mercury can be found in certain types of food, especially certain fish, and is a neurotoxin that can affect development of the brain and nervous system.

Foods that should be fully avoided because of mercury include:

• Fresh or frozen tuna (not canned)

• Shark, swordfish, marlin

Canned light tuna and albacore tuna that is labelled “Product of Canada” come from smaller, younger fish that have much, much lower mercury contents because of the types of food they eat. These types of tuna have been shown consistently to have extremely low-if-any mercury content and are safe to eat during pregnancy.

An important note: The type of mercury found in food and the environement (methylmercury) is a different type of mercury than that found in the vaccine perservative thimerosal (ethylmercury). Thimerosol has been removed from most vaccines. It is still used in some types of flu vaccines and one type of tetanus vaccine. It is not found in the Adacel (tetanus-diptheria-pertussis) vaccine recommended at 26-28 weeks. Please check with your doctor during flu vaccine season about which flu vaccines we have if you are concerned about thimerosal or other ingredients.

Exercise in Pregnancy

Physical activity and exercise are an important part of pregnancy. We are not suggesting that you start training for a marathon in pregnancy, but keeping mobile and active can help you to have a healthier pregnancy. Benefits of exercise in pregnancy include:

• Maintaining mobility and physical strength for labor

• Avoiding excessive weight gain

• Lower risk of a macrosomic (larger than average) baby

• Possible reduction of gestational diabetes, pregnancy-induced high blood pressure, or need for C-section

If you were physically active prior to pregnancy, you can generally continue most of your activities. You should discontinue any contact sports or activities with high risk of falls or impact to the abdomen. You may find that as pregnancy progresses, you need to modify your positions or intensity in activity. Aim for 30 minutes of physical activity 5-7 times per week.

If you were not physically active prior to pregnancy, you can start in pregnancy, but at a slower, more gentle pace. Low-impact activities like walking, swimming, cycling, or yoga are often a good starting place. Start with 20 minute of physical activity 3 times per week and slowly increase the duration, frequency, and intensity as you are able to.

Certain activities should not be done during pregnancy due their risks for you and your baby. These include:

• Hot yoga/hot pilates - the temperature extremes are not good for a developing baby

• Sky diving

• Scuba diving

• Contact sports

• Activities with a high risk of fall

There are also certain conditions in pregnancy that make exercise higher risk. You should talk to your doctor before starting physical activity if you have or have had any of the following:

• Pregnancy high blood pressure problems

• IUGR (a baby that is not growing as well as it should)

• Placenta previa (placenta overlying the cervix)

• History of preterm labor or incompetent cervix

• History of heart or lung disease for yourself

• Vaginal bleeding in pregnancy

There may be other conditions that also make exercise higher risk - if you are not sure, talk to your doctor first before starting physical activity.