Your Baby's Growth and Development In the Third Trimester of Pregnancy

Month Seven of Pregnancy

Video Transcript

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It's the third trimester, and your baby keeps on growing, gaining weight, and getting ready to meet the world. Here's a week-by-week look at the changes. Your little one is about as long as a large bok choy by week 28. Her eyes can open and her toenails are starting to grow in. Next week, she weighs about 3 pounds. She's getting rounder as she gains fat. And her skin's becoming smoother. At week 30, she's about 16 inches long, the length of a bundle of collard greens. Her eyes open, close, and respond to light. Your baby's the length of a rhubarb stalk next week. And she's continuing to put on weight fast. She's around 3 and 1/2 pounds the week after. That makes her almost as hefty as a cantaloupe. Your little one is up to 4 pounds by week 33. She swallows, yawns, and practices breathing. Plus, her brain now controls her body temperature. Next week, she's about as hefty as a sugar pumpkin -- 4 and 1/2 pounds. She's putting on baby fat and her skin isn't see-through anymore. Your baby weighs about 5 pounds by week 35. She keeps practicing her breathing, too. During week 36, she's about 18 and 3/4 inches long. Wow! That's the length of a Swiss chard. Her fingernails have reached the ends of her fingers. Her skin is pink, and those little legs are chubby. Next week, she weighs about as much as a honeydew melon -- 6 pounds. Plus, her bones and muscles are ready for the outside world. The week after, she's about 6 and 1/4 pounds, as heavy as a large cabbage. It's getting awfully crowded in there, and it's almost time to produce this produce. Your little one is about 6 and 1/2 pounds at week 39. Her lungs are ready to breathe and cry. And as she drops into your birth canal, her head molds into a cute little cone shape. By week 40, your baby is around 7 and 1/4 pounds. She's come a long way these last 3 months, and she can't wait to meet you.

At the end of the seventh month of pregnancy, fat begins to be deposited on your baby. Your baby is about 36 cm (14 inches) long and weighs from about 900 - 1800g (two to four pounds). Your baby's hearing is fully developed and he or she changes position frequently and responds to stimuli, including sound, pain, and light.

If born prematurely, your baby would probably survive after the seventh month of pregnancy.

 

28 Weeks

Month Eight of Pregnancy

Your baby, who is now about 46cm (18 inches) long and weighs as much as about 2.27 kg (five pounds), will continue to mature and develop body fat reserves. You may notice that your baby is kicking more. Baby's brain is developing rapidly at this time, and he or she can see and hear. Most internal systems are well developed, but the lungs may still be immature.

32 Weeks

Month Nine of Pregnancy

Towards the end of the third trimester, your baby continues to grow and mature. His or her lungs are nearly fully developed. Your baby's reflexes are coordinated so he or she can blink, close the eyes, turn the head, grasp firmly, and respond to sounds, light, and touch.

Your baby's position changes to prepare itself for labor and delivery. The baby drops down in your pelvis, and usually his or her head is facing down toward the birth canal.

By the end of this pregnancy month, your baby is about 46- 51cm (18 to 20 inches) long and weighs about 3.2kg (seven pounds).

36 Weeks

WebMD Medical Reference Reviewed by Renee A. Alli, MD on November 09, 2017

Sources

SOURCE: Mayo Clinic: ''Fetal development: The third trimester.''

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