The Third Trimester

The last three months of pregnancy start out similar to the second trimester -- lots of energy and planning for the baby. For most women, the third trimester is full of several different things. There is anticipation and excitement over the coming baby, fear and worry about the thought of labor, and growing discomfort as the baby continues to get bigger. By the end, most women are ready to go ahead and have the baby. Click for a week-by-week view of fetal development or learn more about pregnancy at 28 weeks, 29 weeks , 30 weeks , 31 weeks , 32 weeks , 33 weeks , 34 weeks , 35 weeks , 36 weeks , 37 weeks , 38 weeks , 39 weeks and 40 weeks .

Fetal Development

Seventh Month: At the beginning of this month, the baby is about 11 to 14 inches long and weighs between 1 and 1 1/2 pounds. The baby's eyes can now open and close and can see changes in the light outside of the uterus. The baby is starting to get a little cramped in the uterus, but still continues to move and kick. The baby can suck his or her thumb and make grasping motions. By the end of this month, the baby is about 15 inches long and weighs about 2 to 2 1/2 pounds. The baby's chances of survival if born now are much better as he or she continues to grow and develop.

Eighth Month: The baby is continuing to become more ready to be born. The bones are getting stronger, and the baby is continuing to gain more weight. The brain is forming into the different regions and the brain is now directing bodily functions. Taste buds are developing. By the end of this month, the baby is about 16 to 18 inches long and weighs about 4 pounds.

Ninth Month: The baby gains a lot of weight during this month. He or she is gaining about a 1/2 pound a week, which fills out its skin. The baby is getting ready for birth by dropping into a head-down position. He or she can be born any time during this month and be healthy. The baby weighs between 6 and 9 pounds, is about 20 inches long, and is ready to celebrate his or her very first birth day.

Mother's Body

Pregnancy Symptoms: Many of the symptoms from the second trimester continue, but at an increased level. The symptoms that are caused by the pressure and weight of the growing uterus increase as the baby continues to grow. These symptoms include hemorrhoids, varicose veins, swelling in the legs, leg cramps, backaches, and shortness of breath. Braxton-Hicks contractions are common during this trimester as well. These are "practice" contractions where the uterus contracts, hardens for a minute or so, and then relaxes back to normal.

Emotional Changes: It is about this time that women start to become a little bored and tired of being pregnant. The discomforts are increasing, while at the same time the anticipation of the coming baby is increasing. Many women are beginning to feel more and more apprehensive about the health of the baby, labor and delivery, as well as about the thought of becoming a mother. As this trimester progresses and the due date approaches, these back and forth emotions of excitement and anticipation along with worry and apprehension continue to increase.

Physical Changes: As the baby gets bigger, the space in the uterus gets more cramped. As a result there is typically a decrease in fetal movement. Towards the end of the third trimester, the baby will drop to prepare for birth. This head down position decreases the problems with shortness of breath for the mother, but increase the need to make trips to the bathroom.

Weight Gain: Typical weight gain in the third trimester is about a pound a week, but each woman should consult with her doctor to know what weight gain is appropriate for her. A woman of average pre-pregnancy weight should expect to gain a total of between 25 and 35 pounds by the end.

Doctor's Visits

When to See the Doctor: At about 30 weeks, prenatal visits should increase to occur every 2 to 3 weeks. After 36 weeks, visits should occur every 1 to 2 weeks until delivery.

Third Trimester Prenatal Appointments: The checks from previous doctor's visits continue (weight, blood pressure, urine tests, fetal heart rate, and fundal height). If a woman is Rh-negative, she will receive a Rh-immune globulin injection between 28 and 29 weeks. She will also be tested between weeks 35 and 37 for Group-B strep (which is a potentially deadly infection that could be passed on to the baby during delivery). The doctor will also start to do internal and external exams to check the baby's size, whether the baby has dropped, as well as to check the cervix for effacement and dilation. These are all to check for progress towards labor.

Problems to Watch Out For

Bleeding: Bleeding at this stage is typically caused by placenta previa, or a placenta that is blocking the mouth of the uterus. This can be diagnosed by ultrasound, and may require a cesarean-section since the placenta is blocking the baby's passage into the birth canal.

Premature Labor: Premature labor is labor that occurs before the baby is full-term. The baby is considered full-term at 37 weeks. The baby has a very good chance of survival anytime during the third trimester, but ideally, the premature labor can be stopped with medication and bedrest, since the baby requires extensive medical care if born too early. Symptoms of premature labor are the same as of regular labor.

Stillbirth: The occurrence of stillbirth is fairly rare these days. Advances in fetal monitoring equipment have decreased the likelihood of the baby dying. However, stillbirth does still sometimes occur and is considered one of the most difficult experiences a woman will ever have to go through. Women who have experienced a stillbirth should be allowed to grieve their baby's death and be surrounded by support and love, just like any other mother who has lost a child.

Reprinted with permission from American Pregnancy Association