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During Your Third Trimester Resources from UPMC in South Central Pa.

During your third trimester, also called the perinatal period, you will continue to gain weight and may even experience false labor contractions, called Braxton-Hicks contractions. If you plan to take any childbirth, breastfeeding or parenting classes, now is the time to schedule them. You may also want to work with your partner to develop a plan for your labor and delivery.

Prenatal Visits

During your third trimester, your physician will change the schedule of your prenatal visits from monthly to every two weeks. During your last month of pregnancy, you will likely visit your physician once a week. Your physician will check a number of things, including:

  • Any symptoms or discomforts that you are experiencing
  • Your weight and blood pressure
  • Your urine, for protein and sugar
  • The growth, size, position and development of your baby
  • The height of the fundus (the top of your uterus)
  • Your baby's heartbeat

Around week 38 of your pregnancy, your physician may do a pelvic exam to determine if you cervix has started to open and thin in preparation for birth. Your physician will also ask if you are having any contractions, talk to you about labor and delivery, and discuss your birth plan.

Your Baby's Development

By the end of the third trimester, your baby is about 19-21 inches long and weighs about six to nine pounds. During your last few months of pregnancy, your baby’s lungs and kidneys continue to mature. Several other developments are taking place, including:

  • Your baby begins to see, hear, suck his or her thumb and cry
  • By week 36 of your pregnancy, your baby's head may engage, or drop into your pelvic area, in a process called lightening
  • Your baby's skull remains soft to make it easier to pass through the birth canal
  • Your baby is covered in vernix, a creamy, protective coating on his or her skin
  • Your baby's head will usually turn downward during the last few weeks of pregnancy

Changes to Your Body

As your baby grows, you may find it difficult to take deep breaths or get comfortable for a good night’s sleep. You may also experience some anxiety about the arrival of your baby. Changes to your body during the third trimester may include:

  • Frequent urination due to the increased pressure on your bladder
  • Edema, or swelling of the ankles, hands and face
  • Increased skin temperature as the fetus radiates body heat and causes you to feel hot
  • Frequent leg cramps
  • Stretch marks on the abdomen, breasts, thighs and buttocks
  • Leaking of colostrum, a fluid in the breasts that nourishes the baby until breast milk becomes available, from your nipples
  • Backaches, hemorrhoids and varicose veins that increase in intensity and severity
  • Increased white-colored vaginal discharge, called leukorrhea, which may contain mucus

If you experience any symptoms that cause you concern, contact your physician immediately.

Your Pregnancy Resources

Online Maternity Patient Pre-Registration Form

Maternity Patient Pre-Registration Form (PDF)

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