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Does watching your weight prevent stretch marks?
Your midwife or GP may have special advice for you if you weigh:
- more than 100kg (about 15.5st)
- less than 50kg (about 8st)
If you’re concerned about your weight or any other aspect of your health while pregnant, ask your midwife or GP for advice.
Read the answers to more questions about pregnancy.
While it is ideal to be a healthy weight before becoming pregnant (ie, a BMI between 18.5 and 24.9), we know that this doesn’t always happen! If you are outside the healthy weight range, you can still help your baby by gaining weight within the recommended range for your BMI category.
Talk to your lead maternity carer about how you can monitor your weight, and for advice about eating and being active during your pregnancy.
If a woman who is underweight becomes pregnant and finds it difficult to put on weight, she can seek advice from her doctor or midwife. Studies suggest that professional dietary advice can help women gain weight and lower the risk of giving birth too early (preterm birth).
Protein supplements have been found to help some underweight women increase their weight. This lowers the risk of their child being born underweight, as well as reducing the risk of having a miscarriage.
However, very protein-rich dietary supplements with a protein content of more than 25% don’t appear to help. Research also suggests that these very high-protein products might limit the growth of the baby.
There is no clear answer to this question yet. Although there are many claims about what causes stretch marks and what might help, none of them have been confirmed in good-quality research.
Whether or not women get stretch marks not only depends on how much weight they gain in total. Factors like how fast they gain weight can make a difference too. For instance, gaining a lot of weight very suddenly can cause more stretch marks than gaining weight gradually. But it’s not clear whether stretch marks can be prevented by keeping your weight down.
Women are constantly surrounded by (nearly always digitally edited) photos of models with supposedly “ideal” bodies. Pregnant women are confronted with these photos too. This makes it difficult for many of them to be happy with their figure, and it can damage their self-image and enjoyment of their body.
The media add to the pressure on pregnant women and mothers by focusing a lot of attention on how quickly celebrities return to their pre-pregnancy figures. But women need to gain weight during pregnancy – and they can’t expect to lose it all again within a few weeks after giving birth.
A lot of women see pregnancy as a time to simply enjoy their belly, curves and the baby growing inside their body – and allow themselves some “time off” from worrying about their size. That can be one of the really pleasant parts of being pregnant.
It could only become a problem if you get too far out of your normal weight range and change your eating habits too much. Then it might be harder to get back to your healthier “pre-baby” weight and lifestyle.
Women who don’t become very overweight when they are pregnant will probably find it easier to get back to normal afterwards. But you don’t have to be thin to be happy and healthy, and have a healthy baby.
Click to enlarge.
In the first trimester (first 12 weeks), most women do not need to gain much weight (usually less than 2 kg) – which is just as well for those who have morning sickness early in pregnancy.
Some women even lose a small amount of weight. If this happens to you, you do not need to be concerned as long as you start to gain weight steadily in the second and third trimesters of your pregnancy.
The table below can be used as a guide to help you work out how much weight you should gain during your pregnancy. Regardless of your BMI at the start of pregnancy, you can still have a healthy weight gain during pregnancy.
Most women do not gain much weight during the first trimester of pregnancy (between a half and 2 kilograms). The rate of weight gain can vary during the rest of your pregnancy and may not be the same every week.
Your baby’s growth and development in the third trimester of pregnancy
CDC: «Tracking Your Weight for Women Who Begin a Twin Pregnancy Underweight.»
When you’re eating moreto nourish the baby girl or boygrowing inside you, that numberon your scale is gonna go up!Your starting weight can giveyou a good idea of how manypoundsyou should gainduring your pregnancy.If you’re underweight,try to gain 28-40 pounds.Normal weight?Shoot for 25-35 pounds.Overweight?Gain 15-25If you’re obese,try to put on 11-20 pounds.Expecting twins or multiples?Your goal weight goes up.Gain 50-62 pounds if you’reunderweight.37-54 if you startedat a normal weight.31-50 if you’re overweight.And 25-42 if you’re obese.When you’re pregnant with onebaby,get about 300 extra caloriesper daystarting in your 2nd trimester.You’ll need more thanthat if you’re having twinsor multiples,so check with your doctor.Put on the extra poundsslowly and steadily.But don’t sweat it if the numberon your scale shoots up onceand then you level out.Work with your doctor to meetyour weight goals.Gain too many poundsand you become morelikely to get high bloodpressure or diabetes.Your chances of deliveringyour baby early or needinga C-section also go up.Your doctor can guide youthrough the whole 9 months.Call her with any weightconcerns or questions you have.
Eating a healthy, balanced diet will help your baby get the nutrients he or she needs and grow at a healthy rate. But how many extra calories do you really need?
Though you do need some extra calories, it’s not necessary to »eat for two.» The average pregnant woman needs only about 300 healthy calories more a day than she did before she was pregnant. This will help her gain the right amount of weight during pregnancy.
Ask your health care provider how much weight you should gain. A woman who was average weightbefore getting pregnant should gain 25 to 35 pounds after becoming pregnant. Underweight women should gain 28 to 40 pounds. And overweight women may need to gain only 15 to 25 pounds during pregnancy.
In general, you should gain about 2 to 4 pounds during the first three months you’re pregnant and 1 pound a week during the rest of your pregnancy. If you are expecting twins you should gain 35 to 45 pounds during your pregnancy. This would be an average of 1 ½ pounds per week after the usual weight gain in the first three months.
It’s especially important to gain the right amount of weight when you’re expecting twins because your weight affects the babies’ weight. And because twins are often born before the due date, a higher birth weight is important for their health. When carrying twins, you may need between 3,000 and 3,500 calories a day.
Pregnancy is a unique time in which your body changes to meet the needs of your growing baby. Your body must store nutrients and increase the amount of blood and other fluids it makes.
Here is an example of how much each component part weighs during pregnancy if your baby’s birthweight is 3.5 kg, and you gained 12.8 kg during your pregnancy:
|Fluid around the baby (Amniotic fluid)||0.9 kg|
|Growth of your womb (uterus)||0.9 kg|
|Growth of your breasts||1.1 kg|
|Increased amount of blood||1.5 kg|
|Increased amount of other body fluids||1.1 kg|
|Storing of nutrients (fat and protein)||3.1 kg|
|Total weight gain based on this example||12.8 kg|
Gaining the right amount of weight during pregnancy through a mixture of good eating and activity choices will make returning to your pre-pregnancy weight easier.
If you were overweight or obese before becoming pregnant but established good eating and activity habits during pregnancy, continuing to do so after your baby is born will help support gradual weight loss.
The greatest amount of weight loss usually occurs in the first 3 months after birth and then continues at a slow and steady rate until 6 months after birth. Breastfeeding helps you return to your pre-pregnancy weight as some of the weight you gain during pregnancy is used as fuel to make breast milk.
WebMD Pregnancy App.
It’s the third trimester,and your baby keeps on growing,gaining weight, and gettingready to meet the world.Here’s a week-by-week lookat the changes.Your little one is about as longas a large bok choy by week 28.Her eyes can openand her toenails are startingto grow in.Next week, she weighs about 3pounds.She’s getting rounder as shegains fat.And her skin’s becomingsmoother.At week 30, she’s about 16inches long, the lengthof a bundle of collard greens.Her eyes open, close,and respond to light.Your baby’s the lengthof a rhubarb stalk next week.And she’s continuing to puton weight fast.She’s around 3 and 1/2 poundsthe week after.That makes her almost ashefty as a cantaloupe.Your little one is up to 4pounds by week 33.She swallows, yawns,and practices breathing.Plus, her brain now controlsher body temperature.Next week, she’s about as heftyas a sugar pumpkin —4 and 1/2 pounds.She’s putting on baby fatand her skin isn’t see-throughanymore.Your baby weighs about 5 poundsby week 35.She keeps practicingher breathing, too.During week 36, she’s about 18and 3/4 inches long.Wow!That’s the lengthof a Swiss chard.Her fingernails have reachedthe ends of her fingers.Her skin is pink,and those little legs arechubby.Next week, she weighs aboutas much as a honeydew melon —6 pounds.Plus, her bones and musclesare ready for the outside world.The week after, she’s about 6and 1/4 pounds,as heavy as a large cabbage.It’s getting awfullycrowded in there,and it’s almost time to producethis produce.Your little one is about 6and 1/2 pounds at week 39.Her lungs are ready to breatheand cry.And as she drops into your birthcanal, her head moldsinto a cute little cone shape.By week 40, your babyis around 7 and 1/4 pounds.She’s come a long waythese last 3 months,and she can’t wait to meet you.
The U.S. Institute of Medicine (IOM) issues guidelines that are followed by doctors around the world. Their recommendations about BMI and weight gain in pregnancy are as follows:
For women who are underweight before pregnancy (BMI of less than 18.5): between 12.5 and 18 kilograms of weight gain during pregnancy.
For women who are of normal weight before pregnancy (BMI of between 18.5 and 24.9): between 11.5 and 16 kilograms of weight gain during pregnancy.
For women who are overweight before pregnancy (BMI of between 25 and 29.9): between 7 and 11.5 kilograms of weight gain during pregnancy.
For women who are obese before pregnancy (BMI greater than 30): between 5 and 9 kilograms of weight gain during pregnancy.
A pregnant woman’s weight alone is not a good indicator of how well her baby is doing – and not even of how fast her baby is growing. That depends on a lot of factors. It is not possible to say for sure how much the baby will weigh at the end of pregnancy.
Because carbohydrates increase blood sugar levels, women who are very overweight or have gestational diabetes are usually advised to cut down on carbohydrates (“carbs”) while making sure that they still get enough fiber, and to generally eat a balanced diet otherwise.
The exact dietary changes to be made will depend on things like how much the woman weighs and how much exercise she gets. Getting special advice from a nutritional therapist can help to avoid adverse effects.
Doing at least 30 minutes of a strenuous physical activity on about three to four days per week is often enough. Suitable types of exercise include swimming, cycling and brisk walking. Women with a greater risk of preterm birth are usually advised to avoid sports altogether. When in doubt, don’t hesitate to ask a gynecologist.
Does avoiding too much weight gain have any advantages?
Putting on too much weight can affect your health and increase your blood pressure.
But pregnancy isn’t the time to go on a diet, as it may harm the health of the unborn child.
It’s important that you eat healthily.
Gaining too much weight can increase your risk of complications.
- gestational diabetes: too much glucose (sugar) in your blood during pregnancy can cause gestational diabetes, which increases your risk of having a large baby
- pre-eclampsia: a rise in blood pressure can be the first sign of pre-eclampsia; although most cases are mild and cause no trouble, it can be serious
Gaining too little weight can cause problems such as premature birth and a baby with a low birth weight (less than 2.5kg or 5.5lb at birth).
It can also mean your body isn’t storing enough fat.
Lack of weight gain can be related to your diet and weight before you become pregnant.
But some naturally slim women stay slim while they’re pregnant and have healthy babies.
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.
For example: if you are 1.68 m tall and weigh 82 kg:
Your BMI = = 29 kg/m2 = Overweight category (orange colour)
The Kidspot website has an online tool that can help you calculate your BMI.
Alternatively, you can use the chart below to help you. Find your height, then go across the chart till you are in the column headed by your weight (kg). The number in the cell is your BMI (rounded to the nearest whole number). The colour of the cell indicates which recommendations are right for you.
Here are some tips to help you manage healthy weight gain during pregnancy.
- Pregnancy is not about ‘eating for two’. In the first 12 weeks of pregnancy, you can eat the same amount as you usually would. It is important you eat healthy food.
- After the 12th week, and if you are a healthy weight, the extra food you need each day is about the same as a wholegrain cheese and tomato sandwich, or a wholegrain peanut butter sandwich and a banana. If you are overweight or obese, the extra food you need is about the same as 1 slice of wholegrain bread or 2 apples.
- Drink water rather than sweetened drinks or fizzy drinks.
- Drink low-fat [trim (green top) or calcium-extra (yellow top)] or light blue milk instead of full-fat (blue or silver top) milk.
- Choose wholegrain bread instead of white bread.
- Eat a healthy breakfast every day, such as wheat biscuits or porridge with low-fat milk, or 2 slices of wholegrain toast.
- Have at least 4 servings of vegetables and 2 servings of fruit every day. Buy vegetables and fruits that are in season, or buy frozen vegetables to help reduce cost, wastage and preparation time. Tinned fruit in juice are also a good option.
- Examples of a vegetable or fruit serving:
- half a cup of peas, broccoli or carrots
- 1 medium-sized potato, banana, orange or apple
- 1 large kiwifruit.
- If vegetable/fruit juice or dried fruit is consumed, it contributes a maximum of only 1 serving of the total recommended number of daily servings for fruit/vegetables.
- Examples of a vegetable or fruit serving:
- Prepare and eat meals at home. Have takeaways no more than once a week.
- Choose healthy snacks such as unsweetened or low-sugar, low-fat yoghurt, fruit, cheese and crackers, home-made popcorn, a glass of trim milk, a few unsalted nuts (eg, 6 or 7 almonds) or a small wholegrain sandwich.
- Aim to do at least 30 minutes of moderate intensity activity 5 or more days a week, eg, brisk walking or swimming (or as advised by your doctor, midwife or physiotherapist). The ‘talk test’ is a simple way to estimate intensity: as a guide, you should be able to carry out a conversation but not sing while doing moderate intensity activity.
(The Ministry of Health acknowledges the work of E Jeffs and Canterbury DHB in producing these tips.)
Pregnancy can lead to changes in many of your daily routines and habits, including what you eat and how much exercise you get. But most of all: Women’s bodies change during pregnancy to ensure that their unborn children get enough food and other things that they need.
These changes already start happening in early pregnancy, and become more and more noticeable as time goes on. Women gain more weight in the final months of pregnancy than they do in the first few months.
This isn’t only due to the weight of the growing baby. Much of the weight gained is extra fluid (water) in the body. This is needed for things like the baby’s circulation, the placenta and the amniotic fluid.
Medical guidelines used to be quite strict, with recommendations limiting weight gain to a few kilograms. But there is no standard recommended amount of weight gain that applies to every pregnant woman.
Women who gain a lot of weight in pregnancy have a higher risk of certain health problems and complications during childbirth. For instance, they are more likely to have a very big child with a birth weight of over 4,000 g or 4,500 g (macrosomia), and are more likely to need a Cesarean section.
They are also more likely to have difficulties losing the extra weight after giving birth.
On the other hand, if a woman doesn’t gain enough weight and doesn’t get enough different foods in pregnancy, it can harm her growing baby: babies are then often born too early (preterm birth) or often weigh too little at birth.
Paying special attention to diet and getting more exercise during pregnancy may lower certain health risks. This will depend on several factors, including whether the woman is overweight or has gestational diabetes. Research hasn’t shown any advantages for women who have a normal weight.
But women who are very overweight (BMI of over 30) can lower their risk of gestational diabetes by changing their diet and getting more exercise. Previous studies haven’t shown that this will lower the risk of complications during childbirth or prevent the need for a Cesarean section, though.
Women with gestational diabetes are advised to change their diet in order to lower their blood sugar levels. That can lower the risk of complications during childbirth.
Very fast weight gain as a sign of health problems
If a woman puts on weight very suddenly, or if she generally gains more than half a kilogram per week, her weight will be monitored by a doctor or midwife. Additional tests and examinations might be needed too.