HOME  •  HEALTH  •  LIBRARY  •  AREAS  •  CENTERS  •  BOARDS  •  CHATS  •  JOIN FREE

Week 21
MDAdvice.com Home > Health Library > Your Pregnancy: Week by Week > Previous Week > Contents > Next Week

How Big Is Your Baby?

Your baby is getting larger in this first week of the second half of your pregnancy! It now weighs about 10.5 ounces (300g), and its crown-to-rump length is about 7.2 inches (18cm). It is about the size of a large banana.

How Big Are You?

You can feel your uterus about half an inch (1cm) above your bellybutton. At the doctor's office, your uterus measures almost 8.5 inches (21cm) from the pubic symphysis. Your weight gain should be between 10 and 14 pounds (4.5 and 6.3kg).

By this week, your waistline is definitely gone. Your friends and relativesłand strangers, toołcan tell you're pregnant. It would be hard to hide your condition!

How Your Baby Is Growing and Developing

The rapid growth rate of your baby has slowed. However, the baby continues to grow and to develop. Different organ systems within the baby are maturing.

The Fetal Digestive System

The fetal digestive system is functioning in a simple way. By the 11th week of pregnancy, the small intestine begins to contract and relax, which pushes substances through it. The small intestine is capable of passing sugar from inside the small intestine into the baby's body.

By 21 weeks of pregnancy, development of the fetal digestive system enables the fetus to swallow amniotic fluid. After swallowing amniotic fluid, the fetus absorbs much of the water in it and passes unabsorbed matter as far as the large bowel.

Fetal Swallowing

As mentioned above, your baby swallows before it is born. Swallowing by the baby at different stages of pregnancy can be observed by ultrasound. We have seen babies swallowing amniotic fluid as early as 21 weeks of pregnancy.

Why does a baby in the womb swallow? Researchers believe swallowing amniotic fluid may help growth and development of the fetal digestive system. It may condition the digestive system to function after birth.

Studies have determined how much fluid a fetus swallows and passes through its digestive system. Evidence indicates babies at full-term may swallow large amounts of amniotic fluid, as much as 17 ounces (500ml) of amniotic fluid in a 24-hour period.

Amniotic fluid swallowed by the baby contributes a small amount to its caloric needs. Researchers believe it may contribute essential nutrients to the developing baby.

Meconium

During your pregnancy, you may hear the term meconium and wonder what it means. It refers to undigested debris from swallowed amniotic fluid in the fetal digestive system. Meconium is a greenish-black to light-brown substance that your baby passes from its bowels several days or weeks before delivery, during labor or after birth.

Passage of meconium into the amniotic fluid may be caused by distress in the fetus. Meconium seen during labor may be an indication of fetal distress.

If a baby has had a bowel movement before birth and meconium is present in the amniotic fluid, the fetus may swallow the fluid. If meconium is inhaled into the lungs, the baby could develop pneumonia or pneumonitis. For this reason, if meconium is seen at delivery, an attempt is made to remove it from the baby's mouth and throat with a small suction tube.

Changes in You

In addition to your growing uterus, other parts of your body continue to change and to grow. You may notice swelling in your lower legs and feet, particularly at the end of the day. If you're on your feet a lot, you may notice less swelling if you're able to get off of your feet and rest for a while during the day.

Blood Clots in the Legs

A serious complication of pregnancy is a blood clot in the legs or groin. Symptoms of the problem are swelling of the legs accompanied by leg pain and redness or warmth over the affected area in the legs.

The problem has many names, including venous thrombosis, thromboembolic disease, thrombophlebitis and lower deep-vein thrombosis. The problem is not limited to pregnancy, but pregnancy is a time when it is more likely to occur. This is due to the slowing of blood flow in the legs because of uterine pressure and changes in the blood and its clotting mechanisms.

The most probable cause of blood clots in the legs during pregnancy is decreased blood flow, also called stasis. If you have had a previous blood clotłin your legs or any other part of your bodyłtell your doctor at the beginning of pregnancy. It's important information, and he or she needs to know it.

Deep-Vein Thrombosis

A distinction is often made between superficial thrombosis and deep-vein thrombosis in the leg. A blood clot in the superficial veins of the leg is not as serious. This condition is usually noted in veins close to the surface of the skin that can often be felt on the surface. This type of clot is treated with a mild pain reliever such as acetaminophen (Tylenol), elevation of the leg, support of the leg with an ace bandage or support stockings and occasionally heat. If the condition doesn't improve rapidly, deep-vein thrombosis must be considered.

Deep-vein thrombosis is more serious; it requires diagnostic and treatment steps. Symptoms of deep-vein thrombosis in the lower leg can differ greatly, depending on the location of the clot and how bad it is. The onset of deep-vein thrombosis can be rapid, with severe pain and swelling of the leg and thigh.

With deep-vein thrombosis, the leg may occasionally appear pale and cool, but usually a portion of the leg is tender, hot and swollen. Often skin over the affected veins is red. There may even be streaks of red on the skin over veins where blood clots have occurred.

Squeezing the calf or leg may be extremely painful, and it may be equally painful to walk. One way to tell if you have deep-vein thrombosis is to lie down and flex your toes toward your knee. If the back of the leg is tender, it is a positive indication of this problem (Homan's sign). (This type of pain may also occur with a strained muscle or a bruise.) Check with your doctor if this occurs.

Diagnostic studies of deep-vein thrombosis may be different for a pregnant woman than for a nonpregnant woman. In the nonpregnant woman, an X-ray may be accompanied by an injection of dye into leg veins to look for blood clots. This test is not usually performed on a pregnant woman because of exposure to radiation and dye.

Ultrasound is used to diagnose this problem in pregnant women. Most major medical centers offer it, but the test is not available everywhere.

Treatment of deep-vein thrombosis usually consists of hospitalization and heparin therapy. Heparin (a blood thinner) must be given intravenously; it cannot be taken as a pill. It is safe

during pregnancy and is not passed to the fetus. A woman may be required to take extra calcium during pregnancy if she receives heparin because it thins the blood to prevent the clot from enlarging. While heparin is being administered, the woman is required to stay in bed. The leg may be elevated and heat applied, and mild pain medicine is prescribed.

Recovery time, including hospitalization, may be 7 to 10 days. After this time, the woman continues taking heparin until delivery. Following pregnancy, she will need to continue taking a blood thinner for up to several weeks, depending on the severity of the clot.

If a woman has a blood clot during one pregnancy, she may need to use heparin during subsequent pregnancies. If so, heparin can be given by an in-dwelling I.V. catheter or by daily injections the woman administers to herself under her doctor's supervision.

Another medication used to treat deep-vein thrombosis is warfarin, an oral medication. Warfarin (Coumadin«) is not given during pregnancy because it crosses the placenta and can be harmful to the baby. Warfarin is usually given to the woman after pregnancy to prevent blood clots. It may be prescribed for a few weeks or a few months, depending on the severity of the clot.

If you have had a blood clot in the past for any reason, pregnancy-related or not, it's important to see your doctor early in pregnancy. Tell him or her about any problems you've had with blood clots at your first prenatal visit.

The greatest danger from deep-vein thrombosis is a pulmonary embolism, in which a piece of the blood clot breaks off and travels from the legs to the lungs. This is a rare problem during pregnancy and is reported in only 1 in every 3000 to 7000 deliveries. Although it is a serious complication in pregnancy, it can often be avoided with proper treatment.

How Your Actions Affect Your Baby's Development

Safety of Ultrasound

On page 181 is an illustration of an ultrasound exam, accompanied by an interpretive illustration. These show a baby inside a uterus; the mother-to-be has a large cyst in her abdomen.

Many women wonder about the safety of ultrasound exams. Most medical researchers agree ultrasound exams do not pose any significant risk to you or your baby. Researchers have looked for potential problems many times without finding evidence the test causes any.

Ultrasound is an extremely valuable tool in diagnosing problems and answering some questions during pregnancy. Information that ultrasound testing provides can be reassuring to the doctor and the pregnant woman.

If your doctor has recommended ultrasound for you and you're concerned about it, discuss it with him or her. Your doctor may have an important reason for doing an ultrasound exam. It could affect the well-being of your developing baby.

You Should also Know

In the early weeks of pregnancy, your body did not change significantly. Now your body is changing rapidly. Your uterus is large enough to make it clear you are pregnant. Should you be making changes at this point in your pregnancy?

Exercise

Everyone has heard stories of women who continued with strenuous exercise or strenuous activities until the day of delivery without problems. Stories are told of Olympic athletes who were pregnant at the time they won medals in the Olympic games. This kind of training and physical stress probably isn't a good idea for you.

As your uterus grows and your abdomen gets larger, you may find your sense of balance is affected. You may feel clumsy. This isn't the time for contact sports, such as basketball, or sports where you might fall easily, injure yourself or be struck in the abdomen.

Karen had been exercising since before pregnancy, and she wanted to know if she should continue. I reassured her that it would help her feel better and might help control her weight, but she needed to be wise about her choices.

I told her that she was going to have to ease up a little. This point in pregnancył21 weeksłwas a good time for her to begin decreasing the amount or intensity of exercise she was doing.

Listen to your body. It'll tell you when it's time to slow down.

Sexual Relations

Pregnancy can be an important time of growing closer to your partner. As you get larger, sexual intercourse may become difficult because of discomfort for you. With some imagination and with different positions (ones in which you are not on your back and your partner is not directly on top of you), you can continue to enjoy sexual relations during this part of your pregnancy.

If you feel pressure from your partnerłeither his concern about the safety of intercourse or requests for frequent sexual relationsłdiscuss it openly with him. Don't be afraid to invite your partner to visit your doctor with you to discuss these things.

If you're having problems with contractions, bleeding or complications, talk with your doctor about whether you should continue to have sexual relations with your partner.

Previous Week > Contents > Next Week

Send This Article to a Friend

Return to Health Library Main Page

From Your Pregnancy Week by Week by Glade B. Curtis, M.D., OB/GYN. Copyright by Fisher Books. Electronic rights by Medical Data Exchange.

 Home  |  Help  |  Feedback  |  Privacy Policy  |  Register  |  Contact Us  |  Visitor Survey  |  Subscribe to HealthMail  |  Advertising  |  About MDAdvice.com

Copyright © The Online Medical Network Inc. All rights reserved. All material provided by MDAdvice.com is intended for informative purposes only and is not a substitute for professional medical advice. Please consult your physician with any questions or concerns you may have regarding your health. Use of this site indicates your agreement with the Terms of Use.