Week 31
Baby: Your baby can hear distinct sounds, including familiar voices and music. All major organ development is done, although the lungs are still immature. At this stage, your baby starts gaining weight rapidly. Measured from head to heel, your baby is as long as a stalk of rhubarb: 16.5 in.
Mom-to-be: Your uterus now fills a large part of your abdomen, and you've probably gained 21-27 pounds. Stretch marks may be more noticeable now, especially near your belly button. You're probably anticipating the birth -- it won't be long now.
Tip of the Week: Practice your breathing and relaxation exercises.
Week 32
Baby: Your baby measures about 18.9 inches long from head to toe and weighs almost 4 pounds. At this stage, they grow faster than ever. Baby fills almost all the space in your uterus now but may still have enough room to do somersaults. A layer of fat is forming under your baby's skin. The baby is practicing opening their eyes and breathing.
Mom-to-be: You may still be gaining 1 lb. a week. You'll probably start seeing your practitioner every 2 weeks until the last month, when you'll likely switch to weekly visits. You may continue to get backaches and leg cramps. You may also notice a yellowish fluid, called colostrum, leaking from your breasts -- it comes before milk production. Your sex drive might decrease as you move into your last weeks of pregnancy.
Tip of the Week: The top of your uterus is now about 6 inches above your belly button. But you might be carrying differently from others at the same stage of pregnancy. Whether you're carrying higher or lower, bigger or smaller, wider or more compact depends on the size and position of the baby, your body type, and how much weight you've gained. For more comfort, drink plenty of fluids, elevate your legs when sitting, lie on your left side, and wear support stockings.
Week 33
Baby: The next few weeks will mark lots of growth in the baby. The baby will gain more than half its birth weight in the next 7 weeks. Your baby's brain can now control its body temperature. It begins to move less now as it runs out of room -- at least eight movements every 2 hours that can be felt -- and curls up with knees bent, chin resting on chest, and arms and legs crossed. Baby likes to swallow and yawn.
Mom-to-be: You've probably gained 22 to 28 pounds by now. Of the pound a week you're gaining now, roughly half is going to your baby. Smaller meals could feel more comfortable as your uterus crowds your belly.
Tip of the Week: It's safe to keep having sex with your partner, though you may be too uncomfortable. Talk with your partner about other ways to remain intimate, including back rubs and foot massages.
Week 34
Baby: Your baby measures about 19.8 inches from head to toe and weighs about 5 pounds. They grow more baby fat, becoming plumper. Organs are now almost fully mature, except for lungs, and the skin is pink instead of red. Fingernails reach the ends of fingers, but toenails are not yet fully grown. The baby might have lots of hair and may not move as often, due to the tight fit.
Mom-to-be: Your uterus hardens and contracts as practice for labor, known as Braxton Hicks contractions, but you may not feel them yet. Your pelvis has expanded and may ache, especially at the back. The uterus is pushed hard against your lower ribs and your rib cage may be sore, and your navel is probably pushing out as a result of your abdomen being stretched.
Tip of the Week: Start thinking about whether you want to try breastfeeding. You may want to consult a lactation expert or simply talk with friends or relatives who can share their experiences.
What's Happening Inside You?
By the end of these 4 weeks, your baby will weigh as much as 5 pounds. Your babyc ontinues to mature and develop reserves of body fat. You may notice that your baby is kicking more. The baby's brain is developing rapidly at this time, and they can hear. Most internal systems are well developed, but the lungs may still be immature.
Source https://www.webmd.com/baby/guide/your-pregnancy-week-by-week-weeks-31-34