Pregnancy is a time of changes within the body. It is normal to gain some weight during pregnancy due to the growth of the baby, placenta and fluid around the baby (amniotic fluid).
However, too much extra weight during pregnancy can increase your chances of:
- High blood pressure with complications in pregnancy (pre-eclampsia)
- Diabetes during pregnancy (gestational diabetes)
- Needing a caesarean section
- Having a large baby. This increases their risk of becoming obese in childhood and early adult life
- Difficulty losing weight after your baby is born. This may increase your risk of developing diabetes, heart disease and some cancers later in life.
Not gaining enough weight during pregnancy can increase the chances of having a premature (preterm) birth, or a small for age baby
It is good to start your pregnancy at a healthy weight. Do not try to lose weight during your pregnancy.
How much weight should I gain?
The amount of weight that you should gain during pregnancy depends on your pre-pregnancy body mass index (BMI). This is your weight (measured) in kilograms divided by your height (measured) in metres squared. You can ask your health practitioner to help you with this, especially if you do not have accurate scales at home.
pregnant female healthy isolated on white background
For example: if you are 1.68 m tall and weigh 82 kg:
Your BMI = 82 kg/(1.68 m x 1.68 m) = 29 kg/m2 = Overweight category (orange colour)
You will need to put on at least 7kg (15 lbs) while pregnant to cover the growth of your baby. The average weight gain during pregnancy is 11.5 to 12.5kg (25 to 28 lbs). Most of this weight gain will take place in the second half of your pregnancy.
The recommended weight gain during pregnancy is 25–35 lb, if you have a Body Mass Index (BMI) within the normal range. Your baby and her support system will make up a good proportion of this, as will the increased pregnancy ﬂuids, fats, and an enlarged uterus. Much of this extra weight will be lost as soon as yourbaby is born. Also, after the birth, some of this extra weight provides nutrients for breast-feeding, which uses up to 500 calories a day.
The most sensible approach to controlling your weight during pregnancy is to eat a healthy diet and get gentle exercise to ensure that weight gain is not too dramatic. You should be aiming to eat around 2,100– 2,500 calories a day, increasing this by 200 calories in the last trimester of pregnancy—the equivalent of a banana and a glass of milk.
If you are underweight, you may need to gain more weight than outlined here.
If you are overweight, you may need to gain less. Your doctor, midwife or dietitian will be able to advise you. Regular gentle physical activity, such as walking or swimming, will help you gain a healthy weight during pregnancy. If you have raised blood pressure, speak to your doctor or midwife before beginning any physical activity.
ASK A… NUTRITIONIST
I’m underweight. Could this affect my pregnancy? You may be more likely to suffer from nutritional defciencies, which could affect the baby’s health; you
are also more likely to give birth prematurely, and have a smallerthan-usual baby, who is more vulnerable to health problems. To gain weight, eat bigger portions and choose healthy foods that have plenty of protein, goodquality fats, and unrefned carbohydrates. Opt for
nutrient- and calorie-dense foods, such as avocados and whole-milk dairy products; eat lots of leafy greens to ensure you are getting key vitamins and minerals . Eat healthy snacks, such as nuts, fruit, and seeds, and don’t skip breakfast. Your doctor will refer you to a dietician, if necessary