Pregnancy is the time period between the conception and the birth of a child. Measured from the start of a woman's last normal menstrual period (LMP), a full term pregnancy is considered to be 40 weeks, or roughly 9 calendar months.
Key concerns about diet during each of the three stages are outlined below.
In the months before a woman gets pregnant, her food choices are important in several ways. What she eats and the vitamins she takes can help ensure that both she and her child will have nutrients that are essential from the very start of pregnancy. Some diets and activities affect key nutrients and hormones.
A woman should talk to her healthcare professional before trying to become pregnant, especially if she: is a strict vegetarianis a long-distance runner or does other kinds of strenuous exerciseis dieting to lose weighthas, or has had, anemia
A B-vitamin called folate can help prevent certain birth defects of the spine and brain called neural tube defects. The unborn child's neural tube starts to form a few weeks after conception, usually before a woman knows that she is pregnant. For that reason, the US Public Health Service advises all women of childbearing age to take 400 micrograms (mcg) a day of folic acid, a synthetic form of folate. This has been shown to help cut down the risk of neural tube defects. Most multivitamins supply this amount.
Just as it is important to stay active and get plenty of sleep during pregnancy, a woman needs to eat well, too. Her body and her growing child have special nutritional needs. The best way meet these needs is to eat a variety of foods from all the food groups. Skipping meals, eating poorly, and trying to diet while pregnant can be serious threats to the development of the child.
After the first trimester, in fact, a woman should add about 300 calories a day of healthy foods to her diet. She should expect to gain between 25-30 pounds during her pregnancy. This weight is not only baby, placenta, and water, but also extra stores of body fat and blood volume that a woman needs during pregnancy.
Below is a list of special nutritional needs during pregnancy. A woman who is not sure if she is meeting these needs should consult her healthcare professional.
Carbohydrates give the unborn child the constant supply of energy it needs for growth. Most of a woman's extra calories during pregnancy should come from carbohydrates. Foods such as fresh fruit, whole grain cereals and breads, rice, potatoes, and beans are good sources.
Iron supports the growth of the unborn child and helps a woman produce more blood. If the mother does not get enough iron, the baby will take the iron it needs from her blood. Pregnant women should get about 30 milligrams (mg) of iron a day. Most women do not start pregnancy with enough iron in their blood. The doctor may prescribe an iron supplement to prevent iron deficiency anemia.
Foods that contain iron include meat, poultry, fish, legumes such as beans, and whole-grain and enriched grain products. Iron from animal products is better absorbed by the body than that from plant sources. Eating good sources of vitamin C, such as citrus fruit, broccoli, and tomatoes, can help the body absorb more iron.
Folic acid is key to the development of the spinal cord. It helps make new cells and genetic material. Its most important job is helping to prevent neural tube defects, such as spina bifida.
During pregnancy, the recommended daily amount of folic acid rises to 600 mcg. Based on the woman's medical history and test results, the doctor may recommend 400-800 mcg of folic acid a day. Many foods are fortified with folic acid, including those made with enriched flour or grain products, such as bread and rice. This makes it easier for a woman to get all the folic acid she needs before and during pregnancy. Other food sources include green leafy vegetables such as spinach and broccoli, dark yellow vegetables, and fruits such as mangoes, papaya, peaches and pumpkin, beans, and nuts.
Protein is needed for the growth and repair of muscles and body cells in mother and child. During pregnancy, the recommended daily allowance, called the RDA, for protein is 70 grams a day. Good sources of protein include lean meats, fish, legumes, eggs, and skinless poultry. An eating plan that follows the USDA Food Guide Pyramid should provide enough protein for a healthy pregnancy.
Calcium and phosphorus help to form the bones of the unborn child. The RDA for calcium is 1,000 mg for most pregnant women over age 18, and 1,300 mg for pregnant women under age 18. If a pregnant woman does not get enough calcium, the baby will take what it needs from calcium stored in her bones. Milk, yogurt, and other dairy products are the best sources of calcium.
Other vitamins and minerals are also needed in higher amounts than usual during pregnancy. Except for iron, folic acid, and calcium, most of the nutrients needed during pregnancy can be taken in by making healthy food choices. However, a healthcare professional may prescribe a vitamin and mineral supplement. If so, it should be taken only as directed.
Constipation is a common problem during pregnancy. Coupled with pressure from the baby, it can sometimes lead to hemorrhoids. To help prevent constipation, a woman should try to: eat foods high in fiber, such as raw fruits, raw vegetables, beans, bran, and whole-grain breads. Prunes, prune juice, and figs are also helpful.drink 8-12 glasses of fluid a day. Water is a great choice. Nonfat milk and some 199% juices are helpful, too.be physically active. A woman should first check with her healthcare professional before starting any type of exercise during pregnancy.
Many pregnant women experience the nausea and vomiting known as morning sickness. Good dietary choices may help ease these symptoms. A woman may find that it helps to: eat only foods that are appealing. She may find she prefers certain flavors or textures. In the early months of pregnancy, getting enough calories is more important than eating a perfectly healthy diet. Odd combinations sometimes help a woman break the cycle of nausea and poor appetite. When morning sickness starts to taper off, usually around the end of the first trimester, a woman should start to focus on healthy foods again.avoid strong smells. These can sometimes trigger nausea.try to eat something before getting out of bed in the morning. Foods such as crackers, plain toast, dry cereal, or anything that appeals can be good choices.eat often and before she feels hungry. When the stomach is empty, it triggers nausea. It is helpful to eat small, frequent meals during the day rather than skipping meals.try to avoid high-fat and fried foods during this time. Again, those types of foods may trigger nausea in some women.eat in bed to keep the stomach full and the blood glucose even. Before going to sleep and before getting out of bed, she may want to eat a high protein snack such as peanut butter or milk.
A woman who is vomiting more than twice a day should consult her healthcare professional. It is hard to get the nutrients needed to stay healthy and support the baby when that much nausea and vomiting are occurring.
In the months after a baby's birth, the new mother needs to keep eating a balanced and healthy diet. Just by doing so, many women will lose weight in the first 4 weeks.
If a woman chooses to bottle feed, her body no longer needs the extra calories that helped her during pregnancy. If a woman is breastfeeding, she continues to need extra fluid, calories, and protein.
A nursing mother needs to eat a typical healthy diet, plus add extra food to produce milk for the baby. She should be eating about 500 more calories a day than her body needed before pregnancy. Calcium is very important for nursing mothers. Milk, yogurt, cheese, cottage cheese, and dark green leafy vegetables are good sources of it.
About 20% of all pregnant women suffer from iron deficiency anemia. It usually occurs later in pregnancy as the baby's need for iron increases. If there is any excess postpartum bleeding, this can become worse. Pregnant women at highest risk are those who are not well-nourished before and/or during pregnancy. It is recommended that all pregnant mothers take a daily iron supplement of 30 to 60 mgs. This is equal to having a diet high in iron-rich foods such as red meats, dried beans and peas, or enriched cereals.
Vitamin A is needed for growth of bones and teeth. However, the body has no method to shed any excess, so a woman needs to be careful not to get only the right amount. Overdoses can produce toxic effects in the baby such as congenital malformations. The RDA for vitamin A is 800 mcg per day.
Planning for Pregnancy, Birth and Beyond. Second Edition, The American College of Obstetricians and Gynecologists
What to Expect when You're Expecting, Eisenberg
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