The Third Trimester: A Guide to Late Pregnancy

By Stacey Feintuch
Reviewed by Alyssa Quimby, M.D. , Jessie Everts, Ph.D.
June 26, 2023
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Your due date is getting closer! The third trimester of pregnancy lasts from week 28 until you deliver. At the end of this trimester, you’ll get to meet your baby. Here’s an overview of how you may feel, what appointments and tests you’ll need, and how your baby will grow and develop in late pregnancy.

Common Third-Trimester Symptoms

As your baby grows to reach their birth weight and your body prepares for delivery, you may experience some new symptoms in the third trimester.

Shortness of Breath

It’s common to sometimes feel short of breath now that your lungs are more crowded. Sitting or standing up straight, with good posture, may help give you a little more room to breathe. Take breaks when you need to catch your breath.


Pregnancy not only means you’re carrying more weight but also affects the connective tissue in your pelvis, making back pain more likely. Try to sit in chairs that support your back. Exercising regularly may help. So can wearing supportive shoes. You can also try heating pads or massage to help with muscle tension.

Braxton Hicks Contractions

It’s common to have irregular and mild contractions during the third trimester. With contractions, you’ll feel tightening of your belly. Braxton Hicks contractions are “practice contractions”—your body’s way of getting ready for labor. Call your doctor, though, if contractions increase in strength and become more frequent and regular. That could be a sign of labor.

Although not every stomach pain is a contraction—gas and constipation are common forms of pregnancy stomach pain—you should call your doctor if you have any severe pain that you haven’t experienced before or that won’t go away, says Teriya M. Richmond, M.D., a board-certified family medicine doctor in private practice in Houston.

Frequent Urination

Your baby is likely moving more into your pelvis, putting pressure on your bladder and causing you to need to make more frequent bathroom trips. You might even find yourself leaking urine, especially when you bend, lift, cough, sneeze, or laugh. Panty liners can help your underwear stay dry.

While frequent urination might be normal, it can also be a sign of a urinary tract infection (UTI), Richmond says. If you’re also having symptoms like pelvic pain, pain when urinating, smelly urine, or back pain, tell your doctor. Usually, a UTI is treated with oral antibiotics, says Richmond.

Swollen Hands or Feet

It’s normal for hands and feet to swell during pregnancy, since the body is producing more blood and body fluids. “Take [your] rings off and keep them off,” advises Sara Twogood, M.D., a board-certified ob-gyn in Los Angeles and co-founder of Female Health Education and the online forum Female Health Collective. Gentle massage, hydration, and exercise can help, she adds.

Leaking Breast Milk

Believe it or not, your body may already be producing breast milk. You may notice a small amount of milk coming from your breasts, especially if you squeeze them, says Twogood. You may also notice some dried milk on your nipple, she says.

If you don’t notice this, don’t worry. It doesn’t happen to everyone and doesn’t predict what your breastfeeding or chestfeeding experience will be like.

Dry, Itchy Skin

It’s normal for skin to feel a little dry and a bit itchy, especially where it’s stretching over your growing bump. But if you're itching all over and have no history of eczema or skin issues, reach out to your doctor, Richmond says.

Itchiness, particularly on the palms of your hands and soles of your feet, can be a sign of cholestasis of pregnancy, which is a liver condition that can occur in late pregnancy. It triggers intense itching without a rash. The condition is risky, so your doctor could recommend early delivery if you have it.

Contact your doctor if you have any concerns about your itchy skin in the third trimester. However, if the reason for it is simply dryness and stretching, it may help to moisturize regularly, stay cool, and wear comfortable clothing made of breathable fabrics.


Headaches are common in pregnancy. But if you get severe ones in the third trimester along with other symptoms like unexplained, rapid weight gain and vision changes, see your doctor, Richmond says. These are signs of preeclampsia, another potentially dangerous pregnancy complication that requires urgent medical care.

For mild headaches with no other symptoms, you may want to ask your doctor whether it’s safe for you to take an over-the-counter pain reliever. For most people, Tylenol (acetaminophen) is considered safe during pregnancy. Eating regular healthy meals, staying hydrated, following a consistent sleep schedule, managing stress, and exercising daily may also help ward off headaches.

Third-Trimester Mental Health

Whether this is your first child or your fifth, it’s normal to feel anxious about giving birth or about how your life will change by taking on a parental role or adding another child to the mix.

“Most of my patients believe they have things covered,” says Abe Shahim, M.D., a board-certified ob-gyn with Manhattan Women’s Health in New York City. “But during the third trimester, things begin to get very real for them.”

Do your best to stay calm in times of stress. Some ways to cope are to write in a journal, to talk to your partner or a trusted friend about your feelings, and to exercise. If you’re feeling nervous about giving birth, talk through your delivery plan with your healthcare providers and support people so you feel comfortable and secure in your plan.

Some people in late pregnancy start to worry about postpartum depression, says Twogood. This is a type of depression that occurs after the baby is born. “I would suggest establishing a relationship with a mental health professional now if people are worried, so they don’t have to do the work of finding and scheduling one when they really need one,” she advises.

You can start with Postpartum Support International, which has a directory of mental health professionals who specialize in mental health during pregnancy and postpartum.

Delivering a baby during a pandemic can cause a whole new set of anxieties. You may worry about you or your baby being exposed to COVID-19, or about the hospital’s rules and regulations. Tell your doctor and the hospital’s delivery coordinator about your feelings. They can help explain everything to you, Richmond says, which may help you feel more at ease.

Third-Trimester Doctor Appointments

You’ll be seeing your doctor more often in the third trimester. You’ll likely go once every 14 days from week 28 to week 36, and then weekly from week 37 on, Twogood says. This might change depending on your individual pregnancy, she adds.

During your third-trimester doctor appointments, your doctor will continue to check your weight, blood pressure, and urine, and discuss how you’re feeling. They’ll check your baby’s size, position, and heartbeat. You’ll likely get an ultrasound to assess the fetal growth. You’ll also discuss signs of labor so you can watch for them and know when to call the office or head to the hospital, Richmond says.

In addition, your doctor may recommend you get the Tdap (tetanus, diphtheria, acellular pertussis) vaccine between weeks 27 and 36, says Twogood, even if you’ve had it in the past. The Tdap vaccine helps protect you and your baby from pertussis, which is also known as whooping cough.

Partners, grandparents, and anyone else who’ll be around the baby should get vaccinated, too. “For any close contacts to the baby, it is recommended to be vaccinated [with Tdap] within the last 10 years maximum,” Twogood says.

It’s a good idea to get a flu shot, too, if it’s flu season.

Third-Trimester Tests and Screenings

You’ll be getting some more tests during the third trimester. Here are a few that you’ll undergo.

Blood Tests

Your blood may be tested again in the third trimester. Doctors may test to see whether you have enough iron around week 28, Twogood says. An iron deficiency may mean you have anemia, a condition that can occur when you don’t have enough red blood cells to bring oxygen to the tissues in your body.

If you’re anemic during pregnancy, it can be treated by taking iron or vitamin supplements. Your doctor may also check your white blood cell count to see how many disease-fighting cells are in your blood, as well as your platelet count, which can help detect blood-clotting issues.

Additionally, your doctor may want you to get rescreened for infectious diseases, including HIV, chlamydia, gonorrhea, syphilis, and hepatitis B.

Group B Strep

Group B streptococcus (strep) is a type of bacteria that can live in your rectum or vagina. It lives on about one-third of women, and it typically doesn’t cause an infection for them, but it could cause an infection for the baby if they’re exposed to it at birth.

You’ll get tested for group B strep around week 36. If your test shows you have it, you’ll likely take antibiotics during labor through an IV to prevent problems.

Stress Tests

If you’ve experienced pregnancy complications, or you go past your due date, your doctor may ask for extra tests to check on the well‑being of your baby.

  • A nonstress test (NST) uses special monitors to measure the baby’s fetal heart rate as they move or as your belly naturally contracts.
  • A contraction stress test checks the fetal heart rate in response to contractions to be sure it’s safe for you to go into labor. If you get one, you’ll be given the hormone oxytocin or asked to rub or squeeze your nipples to cause the contractions.


In some cases, your doctor may order another ultrasound in the third trimester to see how your baby is doing and rule out potential problems. It can be common to have your last ultrasound around weeks 35 to 36 in order to confirm your baby is in a head-down position and to give a final estimate of weight in order to predict birth weight.

Fetal Development in the Third Trimester

By the time you reach the third trimester, “all the structures are formed, but the baby continues to change and develop until birth,” Twogood says. For example, your baby’s brain is formed, but it’ll continue to develop during this time. Your fetus can likely now hear and see, and can cry and suck their thumb.

Most fetuses begin to turn and are in a head-down position by 35 to 37 weeks into pregnancy. But the bones in the baby’s skull stay soft and can move so the head can change its shape to go through the birth canal more easily. Your fetus is getting bigger and heavier and will likely measure 19 to 21 inches long and 6 to 9 pounds at birth.

While the third trimester can be difficult physically and emotionally, it’s also an extremely exciting time. And it ends with the most wonderful finale: meeting your baby.

Now that you know all about the physical and mental changes of the third trimester, as well as how your baby is growing and developing, you probably want to know what will happen after the birth. Read up on what’s in store for you and your baby in our guide to life with your newborn in the fourth trimester.

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