Stages of Pregnancy

What Happens In Each Stage of Pregnancy?

The nine months of pregnancy are divided into three phases of about three months each. These three phases are called trimesters. The first trimester covers week one to the end of week 12, the second trimester covers week 13 to the end of week 26, and the third trimester covers week 27 to the end of the pregnancy. Find out what’s happening with you and your baby in each of these three phases of pregnancy.

1st Trimester (Week 1 to the end of week 12)

Congratulations! Your journey to motherhood is underway. Check out the changes in your body and how your baby grows during the first three months.

Changes in Your Body

During the first three months of pregnancy, or the first trimester, your body undergoes many changes. As your body adjusts to the growing baby, you may have nausea, fatigue, backaches, mood swings, and stress. These things are all normal. Most of these discomforts will go away as your pregnancy progresses. And some women might not feel any discomfort at all! If you have been pregnant before, you might feel differently this time around. Just as each woman is different, so is each pregnancy. As your body changes, you might need to make changes to your normal, everyday routine. Here are some of the most common changes or symptoms you might experience in the first trimester:

Tiredness

Many women find they’re exhausted in the first trimester. Don’t worry, this is normal! This is your body’s way of telling you that you need more rest. After all, your body is working very hard to develop a whole new life. Try these tips to ease exhaustion:

• Get at least eight hours of sleep every night, and a nap during the day when possible.
• When you are tired, rest or relax.
• Start sleeping on your left side. This will relieve pressure on major blood vessels that supply oxygen and nutrients to the fetus. If you have high blood pressure during pregnancy, it is even more important to be on your left side when you are lying down.
• If you feel stressed, try to find a way to relax.

Nausea and Vomiting

Usually called “morning sickness,” nausea and vomiting are common during early pregnancy. For many women, though, it isn’t limited to just the morning. Although it can seem like it will last forever, nausea and vomiting usually go away after the first trimester. Try these tips to help prevent and soothe nausea:

• Eat frequent, small meals (6 to 8 small meals a day) rather than 3 large meals. Avoid fatty, fried, or spicy foods.
• Try eating starchy snacks, like toast, saltines, cheerios, or other dry cereals when you feel nauseated. Keep some by your bed and eat something before you get out of bed in the morning. If you feel nauseous in the middle of the night, reach for these starchy foods. It’s also a good idea to keep these snacks with you at all times, in case of nausea.
• Try drinking carbonated drinks like ginger ale or seltzer water in between meals.
• Ask your doctor if you should change prenatal vitamins if it seems to be making your nausea worse. Sometimes taking your prenatal vitamin at a different time (e.g. at night not in the morning) can also help.
• Ask your doctor about taking vitamin B6 for nausea and vomiting that doesn’t get better with dietary changes.

If you think you might be vomiting excessively, call your doctor. Constant nausea and/or frequent vomiting may mean you have a condition called hyperemesis gravidarum. If you lose too much fluid you might become dehydrated. Dehydration can be dangerous for you and your baby.

Frequency of Urination

Running to the bathroom all the time? Early in pregnancy, the growing uterus presses on your bladder. This causes frequent urination. See your doctor right away if you notice pain, burning, pus or blood in your urine. You might have a urinary tract infection that needs treatment.

Weight gain

During the first trimester, it is normal to gain only a small amount of weight, about one pound per month.

Changes in Your Baby

By the end of the first trimester, your baby is about three inches long and weighs about half an ounce. The eyes move closer together into their positions, and the ears also are in position. The liver is making bile, and the kidneys are secreting urine into the bladder. Even though you can’t feel your baby move yet, your baby will move inside you in response to pushing on your abdomen.

Doctors Visits

During the early months of pregnancy, regular doctor visits (prenatal care) are especially important. Become a partner with your doctor to manage your care. Keep all of your appointments – everyone is important! During the first prenatal visit, you can expect your doctor or nurse to do the following:

• ask about your health history including diseases, operations, or prior pregnancies
• ask about your family’s health history
• do a complete physical exam
• do a pelvic exam with a Pap test
• order lab tests
• check your blood pressure, urine, and weight
• figure out your expected due date
• answer your questions

Get more details on prenatal care.

1st Trimester Tests and Procedures

For special genetic or medical reasons, you may need other lab tests, like blood or urine tests, cultures for infections, or ultrasound exams in the first trimester. Your doctor will discuss them with you during your visits. The most common tests recommended in the first trimester include:

Nuchal translucency screening (NTS)

This new type of screening can be done between 11 and 14 weeks of pregnancy. It uses an ultrasound and blood test to calculate the risk of some birth defects. Doctors use the ultrasound exam to check the thickness of the back of the fetus’ neck. They also test your blood for levels of a protein called pregnancy-associated plasma protein and a hormone called human chorionic gonadotropin (hCG). Doctors use this information to tell if the fetus has a normal or greater than normal chance of having some birth defects. In an important recent study, NTS found 87% of cases of Down syndrome when done at 11 weeks of pregnancy. When NTS was followed by another blood test done in the second trimester (maternal serum screening test), 95% of fetuses with Down syndrome were identified. Like all screening tests, the results are sometimes misleading. In 5% of women who have NTS, results show that their babies have a high risk of having a birth defect when they are actually healthy. This is called a false positive. To find out for sure if the fetus has a birth defect, NTS must be followed by a diagnostic test like chorionic villus sampling or amniocentesis . NTS is not yet widely used. If you are interested in NTS, talk to your doctor. If she is unable to do the test, she can refer you to someone who can. You should also call your insurance company to find out if they cover the cost of this procedure. NTS allows women to find out early if there are potential health problems with the fetus. This may help them decide whether to have follow-up tests.

Chorionic villus sampling (CVS)

CVS is performed between 10 and 12 weeks of pregnancy. In CVS, the doctor inserts a needle through the abdomen or inserts a catheter through the cervix to reach the placenta. The doctor then takes a sample of cells from the placenta. Experts use this sample to look for problems with the baby’s chromosomes. This test cannot find out whether your baby has open neural tube defects. About 1 in 200 women have a miscarriage as a result of this test.

The Second Trimester

You’re adjusting to the new life inside you.

Changes in Your Body

Most women find the second trimester of pregnancy easier than the first. But it is just as important to stay informed about your pregnancy during these months. You might notice that symptoms like nausea and fatigue are going away. But other new, more noticeable changes to your body are now happening. Your abdomen will expand as you gain weight and the baby continues to grow. And before this trimester is over, you will feel your baby beginning to move! Many of the aches and pains you had in the first trimester may continue. So remember to follow the tips from Pregnancy Basics to help prevent and ease these discomforts. Some of the following aches and pains may make their first appearance during the second trimester:

• Pain in the abdomen, groin, and thighs
• Backaches
• Shortness of breath
• Stretch Marks
• Skin Changes
• Tingling in hands and fingers
• Itching on the abdomen, palms, and soles of the feet – Call your doctor if you have nausea, loss of appetite, vomiting, jaundice or fatigue combined with itching. These can be signs of a serious liver problem called cholestasis of pregnancy.

Weight Gain

Everyone gains weight at different rates. On average, it is normal to gain about one pound per week, or about three to four pounds per month during this trimester.

Changes in Your Baby

By the end of the second trimester your baby will weigh about 1 3/4 pounds and be about 13 inches long. With this growth comes the development of fingers, toes, eyelashes, and eyebrows. Around the fifth month, you might feel your baby move! By the end of this trimester, all of your baby’s essential organs like the heart, lungs, and kidneys are formed.

2nd Trimester Tests and Procedures

During the second trimester, you should continue to see your doctor for prenatal care. Most pregnant women have monthly office visits with their doctor or midwife until the end of this trimester. During the second trimester your doctor can use an ultrasound to see if your baby is developing in a healthy way and to find out your baby’s sex. You will also be offered screening tests to look for genetic birth defects. Birth defects result from problems with a baby’s genes, inherited factors that are passed down from the mother and the father at conception. Genetic birth defects sometimes occur in people with no family history of that disorder. Women over the age of 35 have the greatest chances of having a baby with birth defects. Some of the diagnostic and screening tests your doctor might suggest in the second trimester include:

Amniocentesis

This test is performed in pregnancies of at least 16 weeks. It involves your doctor inserting a thin needle through your abdomen, into your uterus, and into the amniotic sac to take out a small amount of amniotic fluid for testing. The cells from the fluid are grown in a lab to look for problems with chromosomes. The fluid also can be tested for AFP. About 1 in 200 women have a miscarriage as a result of this test.

Chorionic villus sampling (CVS)

This test is performed between 10 and 12 weeks of pregnancy. The doctor inserts a needle through your abdomen or inserts a catheter through your cervix in order to reach the placenta. Your doctor then takes a sample of cells from the placenta. These cells are used in a lab to look for problems with chromosomes. This test cannot find out whether your baby has open neural tube defects. About 1 in 200 women have a miscarriage as a result of this test.

Maternal serum screening test

This blood test can be called by many different names including multiple marker screening test, triple test, quad screen, and others. This test is usually given between 15 and 20 weeks of pregnancy. It checks for birth defects such as Down syndrome, trisomy 18, or open neural tube defects. Doctors take a sample of your blood. They check the blood for 3 chemicals: alpha-fetoprotein (AFP) (made by the liver of the fetus), and two pregnancy hormones: estriol and human chorionic gonadotropin (hCG). Sometimes, doctors test for a fourth substance in the blood called inhibin-A. Testing for inhibin-A may improve the ability to detect fetuses with a high risk of Down syndrome. Higher levels of AFP are linked with open neural tube defects. In women age 35 and over, this test finds about 80% of fetuses with Down syndrome, trisomy 18, or an open neural tube defect. In this age group, there is a false positive rate (having a positive result without actually having a fetus with one of these health problems) of 22%. In women under age 35, this test finds about 65% of fetuses with Down syndrome, and there is a false positive rate of about 5%.

Targeted ultrasound

The best time to get a targeted ultrasound is between 18 and 20 weeks of pregnancy. Most major problems with the way your baby is formed can be seen at this time. Some physical defects such as clubbed feet and heart defects may not be seen. Your doctor can also use ultrasound to see if your baby has any neural tube defects, such as spina bifida. In most cases, if you want to find out the sex of your baby, you can ask your doctor during this test. This is not the most accurate test for Down syndrome. Only 1 in 3 babies with Down syndrome have an abnormal second trimester ultrasound.

The Third Trimester

You’re in the home stretch! Start thinking about breastfeeding, learn to spot the signs of labor and get the facts on cesarean sections.

Changes in Your Body

Some of the same discomforts you had in your second trimester will continue. Plus, many women find breathing even more difficult and notice they have to go to the bathroom even more often. This is because the baby is getting bigger and it is putting more pressure on your organs. Don’t worry, your baby is fine and these problems will lessen once you give birth. The following aches and pains often appear for the first time during the third trimester:

• Heartburn
• Swelling of the ankles, fingers, and face. If you notice any sudden or extreme swelling or if you gain a lot of weight really quickly, call your doctor right away. This could be a sign of preeclampsia or toxemia.
• Hemorrhoids
• Tender Breasts
• Trouble Sleeping

As you near your due date, your cervix becomes thinner and softer (called effacing). This is a normal, natural process that helps the birth canal (vagina) to open during the birthing process. Your doctor can check your progress with a vaginal exam.

Weight Gain

Everyone gains weight at different rates. On average, it is normal to gain about one pound per week, or three to four pounds per month, during the third trimester. By the end of your pregnancy you should have gained, on average, about 25 to 30 pounds. About 7 1/2 pounds of that weight should be the baby.

Changes in Your Baby

Your baby is still growing and moving, but now it has less room in your uterus. Because of this, you might not feel the kicks and movements as much as you did in the second trimester. During this final stage of your pregnancy, your baby is continuing to grow. Even before your baby is born it will be able to open and close its eyes and might even suck its thumb. As your body prepares for birth, the baby will start to move into its birth position. You might notice the baby “dropping,” or moving down lower in your abdomen. This can reduce the pressure on your lungs and rib cage, making it easier to breathe. At birth, the average baby is 20 to 22 inches long and weighs 7 1/2 pounds. But newborns who weigh between 5 pounds, 11 1/2 ounces and 8 pounds, 5 3/4 ounces are considered healthy.

Sleeping in the 3rd Trimester

Your energy may lessen as you enter the ninth month. So you may begin to slow down. This is normal. It’s important to get enough rest now, even though it can be more difficult to sleep as you get larger. The baby’s movements, bathroom runs, and an increase in your body’s metabolism can make sleeping difficult. Try these tips for sleeping in the last three months of pregnancy:

• avoid eating large meals three hours before going to bed
• do mild exercise like walking
• avoid taking long naps during the day
• talk with your partner, friends, doctor or midwife to relieve stress

Doctors Visits

Be sure to continue seeing your doctor or midwife regularly. In the last trimester of pregnancy, women usually see their doctors or midwives more frequently. From 30 weeks to 38 weeks of pregnancy, most doctors and midwives recommend one office visit every two weeks. After 38 weeks, women normally see their doctor or midwife every week until delivery. As your due date approaches, ask questions and share concerns you have about labor and delivery. You and your doctor will discuss what kind of delivery you will have. Some women need to have a cesarean section (c-section). During a c-section a surgical cut is made in the abdomen and uterus to remove the baby. If you plan on a non-surgical, vaginal birth, you should talk to your doctor about the pros and cons of pain relief. Some women opt for pain medicines and others want to deliver naturally, without medicine. Many women find childbirth classes very helpful, even if they have already had a baby. Women often bring their partners or a friend or relative to childbirth classes, particularly if this person will be with them during the birth of their baby.

Inducing Labor

Did you know that only five percent of babies are born on their due dates? So being pregnant after your due date is normal and common. And it does not mean anything is wrong. But sometimes the doctor has concerns about the baby’s and/or your health. In these cases, the doctor recommends inducing labor. Inducing labor means that your doctor will start your labor through artificial means. Most doctors will wait one to two weeks after a woman’s due date before considering inducing. Some reasons why doctors induce labor include:

• The mother has a chronic illness like high blood pressure or diabetes that threatens the health of the baby.
• The baby is not growing normally.
• A woman’s “water breaks” which means the membranes that surround the fetus rupture but contractions don’t start within a safe amount of time.

Most doctors induce labor in the hospital to ensure the health of the mother and baby. There are many ways to start contractions. Doctors can rupture the membranes (break the water) surrounding the fetus. They can also insert a suppository containing a hormone into the vagina. Most often, doctors use a medicine called Pitocin to induce labor. Pitocin is a hormone that causes contractions. Women in the hospital receive Pitocin through a vein in the arm or hand.

Deciding to Breastfeed or Bottle-Feed

If you haven’t thought about whether you will breastfeed or bottle-feed your baby, it is time to start. You should learn more about both options and make a decision about what you plan to do. Breastfeeding is much better than formula-feeding for your baby’s health and your own. Find out all the facts about breastfeeding. Talk to your doctor or a pediatrician about breastfeeding. Then make the decision that is right for you. Visit our breastfeeding center to learn more about the benefits, to find out how to make it work best for you, and to get tips on breastfeeding while working.

When to Call Your Doctor

Before your due date, make sure to talk with your doctor about how to reach him or her if you go into labor. It’s also helpful to be familiar with the hospital or birthing center, where you should park, and where to check in ahead of time. Know that sometimes you can think you’re in labor, but really are not (called false labor). This happens to many women, so don’t feel embarrassed if you go to the hospital certain that you are in labor, only to be sent home! It’s always better to be seen by a doctor as soon as possible once labor has begun. Here are the signs of true labor:

Signs of Labor Contractions at regular and increasingly shorter intervals that also become stronger in intensity. Lower back pain that doesn’t go away. You might also feel premenstrual and crampy. Your water breaks (can be a large gush or a continuous trickle) and you have contractions. A bloody (brownish or blood-tinged) mucous discharge. This is the mucous plug that blocks the cervix. Labor could be at any time, or days away. Your cervix is dilating (opening up) and becoming thinner and softer (also called effacement). During a pelvic exam, your doctor will be able to tell if these things are happening.