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This topic covers pregnancy information, including planning for labor and delivery. If you aren't pregnant yet, see the topic Preparing for a Healthy Pregnancy.For more information on labor and delivery, see the topic Labor and Delivery.
You may be happy and excited to find out that you're pregnant. And you may be a little nervous or worried. If this will be your first child, you may even feel overwhelmed by all of the things you need to know about having a baby. There is a lot to learn. But you don't have to know everything right away. You can read all about pregnancy now, or you can learn about each stage as your pregnancy goes on.
Pregnancy is measured in trimesters from the first day of your last menstrual period, totaling 40 weeks. Most babies are born at 37 to 42 weeks.
During your pregnancy, you'll have tests to watch for certain problems that could occur. With all the tests you'll have, you may worry that something will go wrong. But most women have healthy pregnancies. If there is a problem, these tests can find it early so that you and your doctor or midwife can treat it or watch it to help improve your chance of having a healthy baby.
Taking great care of yourself is the best thing you can do for yourself and your baby. Everything healthy that you do for your body helps your growing baby. Rest when you need it, eat well, and exercise regularly. Drink plenty of water before, during, and after you are active. This is very important when it's hot out.
You'll need to have regular checkups. At every visit, your doctor or midwife will weigh you and measure your belly to check your baby's growth. You'll also get blood and urine tests and have your blood pressure checked.
It's important to avoid tobacco smoke, alcohol and drugs, chemicals, and radiation (like X-rays). These can harm you and the baby.
Your first prenatal exam gives your doctor or midwife important information for planning your care. You'll have a pelvic exam and urine and blood tests. You'll also have your blood pressure and weight checked. The urine and blood tests are used for a pregnancy test and to tell whether you have low iron levels (are anemic) or have signs of infection.
At each prenatal visit you'll be weighed, have your belly measured, and have your blood pressure and urine checked. Go to all your appointments. Although these quick office visits may seem simple and routine, your doctor is watching for signs of possible problems like high blood pressure.
In some medical centers, you can have screening in your first trimester to see if your baby has a chance of having Down syndrome or another genetic problem. The test usually includes a blood test and an ultrasound.
During your second trimester, you can have a blood test (triple or quadruple screen test) to see if you have a higher-than-normal chance of having a baby with birth defects. Based on the results of the tests, you may be referred to a geneticist for further discussion. Or you may have other tests to find out for sure if your baby has a birth defect.
Late in your second trimester, your blood sugar will be checked for diabetes during pregnancy (gestational diabetes). Near the end of your pregnancy, you will have tests to look for infections that could harm your newborn.
You will go through some amazing changes during pregnancy. Your body, emotions, and relationships will all do some growing. These changes are common, but some may be a challenge.
Every woman feels these changes in her own way. Even the way she changes can change. In the beginning of your pregnancy, you may feel so tired that you can barely keep your head up. But at other times, you may have trouble sleeping.
Many women feel nauseated in the morning (morning sickness) or at other times of day in the early part of pregnancy. But some women never have this problem. Your breasts will get larger and may feel tender. Throughout your pregnancy, you may get heartburn or crave certain foods, and you may have aches and pains. You also may enjoy the flutters of your baby moving and kicking.
Your emotions may move around too. Even women who are happy about their pregnancy may worry a lot about their babies. They may even feel some sadness at the coming changes in their lifestyles.
Your relationship with your partner and other children you may have also may change. Talk with your partner and with your doctor if you have concerns about how you're feeling.
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The first test you may have is the one you take at home to see if you're pregnant. After you know you're pregnant, you will have a series of tests throughout your pregnancy to make sure you and your baby are healthy.
If you think you might be pregnant, you can use a home pregnancy test as soon as you think you have missed your period.
Pregnancy is measured in weeks from the first day of your last menstrual period. There are several methods to find out your due date.
Use this Interactive Tool: What Is Your Due Date?
As soon as you know you're pregnant, make an appointment with your doctor or certified midwife. Your first prenatal visit will provide information that can be used to check for any problems as your pregnancy progresses. It's also a good time to think about how you want to partner with your doctor or midwife.
Good care during pregnancy includes regularly scheduled prenatal exams. At each prenatal visit, you'll be weighed, have your abdomen measured, and have your blood pressure and urine checked. Use this time to discuss with your doctor or midwife your list of pregnancy concerns or problems.
At different times in your pregnancy, you may have additional exams and tests performed. Although some are routine, others are only done when you ask for them, when a problem is suspected, or if you have a risk factor for a problem.
Tests in the first and second trimester can show if your baby has a birth defect. It's your choice whether to have these tests. You and your partner can talk to your doctor or midwife about birth defects tests.
To learn more about these tests, see the topic Birth Defects Testing.
You can choose from different kinds of tests. If you are worried about the chance of a birth defect, you might want test results as early as possible. If your risk for having a baby with a birth defect is very low or if knowing that your baby has a birth defect wouldn't change your plans, you might decide not to have early tests. Or you might choose not to have these tests at all.
The best way to help yourself have a healthy pregnancy is to eat well, exercise regularly, get plenty of rest, and avoid things that could hurt your baby.
For more tips on how to have a healthy pregnancy, see Quick Tips: Healthy Pregnancy Habits.
To learn more about eating well, see:
Pregnancy is a time of many changes. Your body will go through a lot on the way to creating a new person.
Although they can range from mild to severe, the following conditions are common during pregnancy:
Many pregnant women also have:
The first trimester of pregnancy lasts from week 1 through week 12. Your first sign of pregnancy may be a missed menstrual period. Other early signs of pregnancy, caused by hormonal changes, include:
The second trimester of pregnancy (from week 13 to week 27) is the time when most women start to look pregnant and may begin to wear maternity clothes. By 16 weeks, the top of your uterus, called the fundus, will be about halfway between your pubic bone and your navel. By 27 weeks, the fundus will be about 2 in. (5 cm) or more above your navel.
You may find that the second trimester is the easiest part of pregnancy. For some women, the breast tenderness, morning sickness, and fatigue of the first trimester ease up or disappear during the second trimester, while the physical discomforts of late pregnancy have yet to start. Pressure on your bladder may be less as the uterus grows up out of the pelvis.
Common symptoms you may experience during the second trimester of pregnancy include:
The third trimester lasts from week 28 to the birth. Many women have some discomfort during this time as their belly gets bigger. You might have trouble getting comfortable so you can sleep. And you might have a few other aches and pains.
Common symptoms you may experience during the third trimester include:
Pregnancy is measured in trimesters from the first day of your last menstrual period, totaling 40 weeks. The first trimester of pregnancy is week 1 through week 12, or about 3 months. The second trimester is week 13 to week 27. And the third trimester of pregnancy spans from week 28 to the birth.
Your baby will change from week to week. To learn more about how your baby is changing each month and about what tests you might think about having, see the Interactive Tool: From Embryo to Baby in 9 Months.
During the week after fertilization, the fertilized egg grows into a microscopic ball of cells (blastocyst), which implants on the wall of your uterus. This implantation triggers a series of hormonal and physical changes in your body.
The third through eighth weeks of growth are called the embryonic stage, during which the embryo develops most major body organs. During this process, the embryo is especially vulnerable to damaging substances, such as alcohol, radiation, and infectious diseases.
Having reached a little more than 1 in. (2.5 cm) in length by the ninth week of growth, the embryo is called a fetus. By now, the uterus has grown from about the size of a fist to about the size of a grapefruit.
The first trimester is a time of amazing development. The embryo starts out looking like a tiny seed, then a tadpole with a tail, and then more human.
If this is your first pregnancy, you'll begin to feel your fetus move at about 18 to 22 weeks after your last menstrual period. Although your fetus has been moving for several weeks, the movements have not been strong enough for you to notice until now. At first, fetal movements can be so gentle that you may not be sure what you are feeling.
If you've been pregnant before, you may notice movement earlier, sometime between weeks 16 and 18.
During this time, the fetus is still building up body fat and starting to put on a lot of weight. By the end of the second trimester, your fetus is about 10 in. (25.5 cm) long and weighs about 1.5 lb (680 g).
The third trimester of pregnancy spans from week 28 to the birth. The fetus moves frequently, especially between the 27th and 32nd weeks. After week 32, a fetus becomes too big to move around easily inside the uterus and may seem to move less.
Your due date marks the end of your 40th week. Most babies are born at 37 to 42 weeks. During this final trimester, your fetus grows larger and the body organs mature.
At the end of the third trimester, a fetus usually settles into a head-down position in the uterus. You will likely feel some discomfort as you get close to delivery.
The emotional experience of pregnancy is different for every woman. It's common to have mixed emotions and to feel uncertain—even if your pregnancy was planned.
Because of the increasing hormones and the fatigue of early pregnancy, mood swings can be worse than before pregnancy. Many women worry that their baby will have a problem. Or they may feel anxious about childbirth.
Your relationships with family and friends may change as you adjust to having a new family member.
With all the changes in your life, you may feel stressed at times. Try relaxation exercises and use time management tips and skills at home.
Some women have health problems or concerns before they get pregnant. For other women, problems may come up during pregnancy. Your doctor or midwife will work with you to prevent or manage these problems to help you have a healthy pregnancy.
If you have a health problem or concern, you may have a high-risk pregnancy. This means that your doctor or midwife needs to follow you closely. It doesn't mean that something will go wrong during your pregnancy.
During your prenatal visits, talk with your doctor or midwife about what you would like to happen during your labor. Consider writing up your labor and delivery preferences in a birthing plan, either in a childbirth education class or on your own. You can find examples of birthing plans on parenting websites.
Because no labor or delivery can be fully anticipated or planned in advance, be flexible. Your experience after labor begins may be totally different from what you expected. If an emergency or an urgent situation arises, your plans may be changed for your own or your baby's safety.
When making plans for your baby's birth, consider the location of your delivery, who will deliver your baby, and whether you want continuous labor support from a doula, a friend, or family members. If you haven't already, this is also a good time to decide whether you'll attend a childbirth education class, starting in your sixth or seventh month of pregnancy.
Learn about labor and delivery ahead of time. Think through your preferences for comfort measures, pain relief, medical procedures, and fetal monitoring. And think through how you want to handle your first hours with your newborn. To learn more, see the topic Labor and Delivery.
Plan ahead for breastfeeding by learning about breastfeeding and finding a good lactation consultant ahead of time and buying necessary supplies.
Sometime during your pregnancy, you may get information about cord blood banking. Cord blood is the blood left in the umbilical cord after birth. Think about whether you want to bank your baby's umbilical cord blood for possible future use.
At any time during your pregnancy, call your doctor or midwife immediately if you:
At any time during your pregnancy, call your doctor or midwife today if you:
If you are between 20 and 37 weeks pregnant, call 911 or other emergency services immediately if you:
If you are between 20 and 37 weeks pregnant, call your doctor or midwife immediately or go to the hospital if you:
After 37 weeks, call 911 or other emergency services immediately if you:
After 37 weeks of pregnancy, call your doctor or midwife immediately or go the hospital if you:
To learn more about problems during pregnancy, see the topic Pregnancy-Related Problems.
Current as of
Author: Healthwise StaffMedical ReviewSarah Marshall MD - Family MedicineKathleen Romito MD - Family MedicineAdam Husney MD - Family MedicineElizabeth T. Russo MD - Internal MedicineKirtly Jones MD - Obstetrics and Gynecology
Other Works Consulted
American College of Obstetricians and Gynecologists (2010). Your Pregnancy and Birth, 5th ed. Washington, DC: American College of Obstetricians and Gynecologists.
American College of Obstetricians and Gynecologists (2012). Update on immunization and pregnancy: Tetanus, diphtheria, and pertussis vaccination. ACOG Committee Opinion No. 521. Obstetrics and Gynecology, 119(3): 690–691.
U.S. Department of Health and Human Services, U.S. Environmental Protection Agency (2011). Mercury Levels in Commercial Fish and Shellfish. Available online: http://www.fda.gov/Food/FoodSafety/Product-SpecificInformation/Seafood/FoodbornePathogensContaminants/Methylmercury/ucm115644.htm.
Current as of:
May 29, 2019
Medical Review:Sarah Marshall MD - Family Medicine & Kathleen Romito MD - Family Medicine & Adam Husney MD - Family Medicine & Elizabeth T. Russo MD - Internal Medicine & Kirtly Jones MD - Obstetrics and Gynecology
To learn more about Healthwise, visit Healthwise.org.
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