Fetal development 3rd Trimester Symptoms

The end of a pregnancy is undoubtedly physically demanding. The third trimester is all about preparing for your baby and even though you are probably tired of being pregnant, you are eagerly awaiting the arrival of your little one. However, your uterus is still a busy place because fetal development continues during the third trimester. Read on to find out what week is third trimester, which are the most common symptoms in the 3rd trimester of pregnancy, and how fetal development continues as you approach your due date!

In the third trimester, your precious baby will open his/her eyes, gain weight and will start blinking and dreaming. Your baby also starts having regular sleep and wake cycles and you may feel plenty of kicks, hiccups, flips and other movements. He/she will be also responding to sound, touch, and bright light.

The third trimester can be really challenging and uncomfortable for you, but you're in the home stretch of your pregnancy. In this article, you'll find out what happens during the third trimester and which symptoms are normal.

Common Symptoms In The Third Trimester:

Varicose Veins

The spider veins you have developed in the second trimester due to poor blood circulation might end up as swollen red or blue veins known as varicose veins. They are common during the third trimester of pregnancy and tend to develop mostly in the legs, thighs, and calves. There's no way to avoid those annoying varicose veins in pregnancy and even though they may get worse in the third trimester, they will fade away once your little one is born.

Shortness of Breath

This is completely normal because your uterus expands and presses up into your diaphragm below your lungs. The added pressure on your lungs can make it more difficult to breathe. If you're experiencing shortness of breath, try exercising or prop your upper torso up on a few pillows to expand your airway and to be more comfortable at night.

Continued Breast Enlargement

By the end of your third trimester, your breasts will likely grow a whole 2 pounds. As your breasts continue to grow, you might also notice a yellow discharge leaking from your nipples. This substance is called colostrum and it's actually the first milk your breasts produce during pregnancy. One of the most important things at this point in your pregnancy is to make sure you're wearing a supportive bra so your back doesn't suffer.


Your baby continues to grow in the third trimester and the extra weight you've gained is putting a lot of pressure on your lower back and pelvis. You might feel discomfort when sitting or standing for long periods of time, so to ease the pressure on the back, practice good posture. Massages and flat comfortable shoes with cushioned support will help relieve a backache.


You may notice that your face, hands, feet, and ankles look swollen in the third trimester. This mild swelling is actually the result of excess fluid retention (edema). If you want to reduce bloating, put your feet above your heart with a foot stool or a few pillows. However, if you have a sudden onset of swelling, seek medical attention immediately as this can be a sing of preeclampsia.

Abdominal Pain

Don't be afraid if you're experiencing mild abdominal pain. Carrying a baby puts a lot of pressure on the muscles, veins, and joints, and this can make you feel uncomfortable around your stomach area. Abdominal pain is completely normal during the third trimester. You might also experience Braxton Hicks contractions (warm up contractions) that come and go as you get closer to your due date.

Frequent Urination

Your baby continues to grow and the pressure on your bladder increases, which leads to frequent urination and incontinence (urine leaks). This means that you'll have to visit the bathroom more frequently and you may also notice that you're leaking urine when you sneeze, cough or laugh. In order to avoid this embarrassing situation, wear a panty liner and avoid drinking fluids before sleep.

Weight Gain

By the end of your pregnancy, you should have put on a total of about 25 to 35 pounds. The extra pounds you've gained are made up of your baby's weight, the placenta, increased blood volume, fluid retention, amniotic fluid and added breast tissue. If you think that your baby isn't growing as he/she should be, your doctor will do an ultrasound to check baby's growth.

When does the third trimester begin?

Wondering when does the third trimester start? Your third trimester starts at the beginning of the 28th week and lasts until you give birth, which usually happens around week 40. However, it's likely that labor will start a couple of weeks earlier or later.

Baby development during the third trimester

By the end of the second trimester, all of your baby's organs and body parts are well-developed and working properly. Now everything just needs to grow and mature. Take a look at fetal development third trimester.

Month seven of pregnancy

At the end of the seventh month, fat begins to be deposited on your baby which is probably about 14 inches long and weighs 2 to 4 pounds. Your baby can hear very well at this point and will change positions frequently. He/she will be also responding to sound, light and pain. If born prematurely, your baby would probably survive after month seven of pregnancy.

Month eight of pregnancy

Your baby is about 18 inches long and weighs five pounds by now. The baby will develop body fat reserves in the eight month of pregnancy. Your baby will be kicking more and his/her brain is developing rapidly. Most internal systems are now well developed and he/she can hear and see.

Month nine of pregnancy

Towards the end of your third trimester, your baby continues to mature. His/her lungs are now fully developed and he/she can now turn the head, blink, grasp and respond to touch and sounds. Your baby will be changing positions to prepare itself for labor and delivery. The baby will drop down in your pelvis, and his/her head will be facing down toward the birth canal. By the end of month nine of pregnancy, your baby is about 18 to 20 inches long and weighs about seven pounds.