Third Trimester of Pregnancy: Fetal Development

The third trimester of pregnancy starts in week 28 of your pregnancy and lasts until you give birth, which is around the 40th week. The third trimester can be tiring and more uncomfortable as your baby takes up more room and you experience:
Backaches: Pregnancy hormones relax the connective tissue that holds your bones in place, especially in the pelvic area. These changes can cause backaches and other discomfort during the third trimester. When you sit, choose chairs with good back support.  Get regular exercise. Wear flat or low-heeled shoes with good arch support. Our sponsor, Slumbar has a great pregnancy pillow to help you sleep, sit and be more comfortable.
Shortness of breath: You might get winded easily. Good posture will give your lungs more room to expand.
Heartburn. Pregnancy hormones relaxing the valve between your stomach and esophagus can allow stomach acid to reflux into your esophagus, causing heartburn. To prevent heartburn, eat small, frequent meals and avoid fried foods, citrus fruits, chocolate, and spicy or fried foods. Our sponsor Nightfood’s Nighttime Ice Cream is specially formulated to be easier to digest and uses not artificial sweeteners or erythritol, and contains ingredients that research indicates are effective against heartburn.
Spider veins, varicose veins and hemorrhoids: Increased blood circulation might cause tiny red-purplish veins (spider veins) to appear on your face, neck and arms. You might also experience swollen veins (varicose veins) on your legs, and hemorrhoids. To ease swelling, exercise and elevate your legs frequently, include plenty of fiber in your diet and drink lots of fluids. For hemorrhoid relief, soak in a warm tub or apply witch hazel pads to the area.
Frequent urination. As your baby moves deeper into your pelvis, you’ll feel more pressure on your bladder and the need to urinate more often. This extra pressure might also cause you to leak urine when you laugh, cough, sneeze, bend or lift. If this is a problem, consider using panty liners.

How Your Baby is Developing Now:

Weeks 27 thru 32 – Gestational Age (Fetal Age – Weeks 25 thru 30)

The fetus really fills out over these next few weeks, storing fat on the body, reaching about 15-17 inches long and weighing about 4-4 ½ lbs by the 32nd week. The lungs are not fully mature yet, but some rhythmic breathing movements are occurring. The bones are fully developed but are still soft and pliable. The fetus is storing its own calcium, iron, and phosphorus. The eyelids open after being closed, since the end of the first trimester.

Weeks 33 thru 36 – Gestational Age (Fetal Age – Weeks 31 thru 34)

This is about the time that the fetus will descend into the head-down position preparing for birth. The fetus is beginning to gain weight more rapidly. The lanugo hair will disappear from the skin, and it is becoming less red and wrinkled. The fetus is now 16-19 inches and weighs anywhere from 5 ¾ lbs to 6 ¾ lbs.

Weeks 37 thru 40 – Gestational Age (Fetal Age – Weeks 35 thru 38)

At 38 weeks the fetus is considered full-term and is ready to make its appearance at any time. As your baby becomes bigger, you may notice a change in fetal movement. If you notice a decrease in fetal movement, make sure to talk with your doctor. The fingernails have grown long and will need to be cut soon after birth. Small breast buds are present on both sexes. The mother is supplying the fetus with antibodies that will help protect against disease. All organs are developed, with the lungs maturing all the way until the day of delivery. The fetus is about 19 – 21 inches in length and weighs anywhere from 6 ¾ lbs to 10 lbs.

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