Mayo Clinic Health Library

Prenatal care: 3rd trimester visits

Updated: 08-04-2012

Prenatal care is an important part of a healthy pregnancy, especially as your due date approaches. During the last month of pregnancy, expect weekly checkups.

Repeat the usual drill

Your health care provider will continue to monitor your blood pressure and weight, as well as your baby's heartbeat and movements.

Your health care provider might ask you to keep track of how often you feel the baby move — and to alert your health care team if the baby stops moving as much as usual.

Test for group B strep

Expect to be screened for group B streptococcus (GBS) during the third trimester. GBS is a common bacterium that's usually harmless in adults — but babies who become infected with GBS can become seriously ill.

To screen for GBS, your health care provider will swab your lower vagina and anal area. The sample will be sent to a lab for testing.

If the sample tests positive for GBS — or you previously gave birth to a baby who developed GBS disease — you'll be given intravenous antibiotics during labor. The antibiotics will help protect your baby from the bacterium.

Resume pelvic exams

As your due date approaches, your prenatal visits might include pelvic exams. These exams help your health care provider check the baby's position and detect cervical changes.

Check the baby's position
Near the end of pregnancy, your health care provider can feel your baby's head in your lower abdomen or at the top of the birth canal.

If your baby is positioned headfirst, you're good to go.

If your baby is positioned rump-first or feet-first (breech), your health care provider might try to turn the baby by applying pressure to your abdomen. This procedure is known as an external cephalic version.

If your baby remains in a breech position, you might need a C-section delivery.

Detect cervical changes
As your body prepares for birth, your cervix will begin to soften, open (dilate) and thin (efface). Progress is typically expressed in centimeters (cm) and percentages.

For example, your cervix might be 3 centimeters dilated and 30 percent effaced. When you're ready to push your baby out, your cervix will be 10 centimeters dilated and 100 percent effaced.

Resist the temptation to put much stock in these numbers. You could be dilated to 3 centimeters for weeks — or you might go into labor without any dilation or effacement at all.

Keep asking questions

You might have plenty of questions as your due date approaches.

Is it OK to have sex? How will I know when I'm in labor? What's the best way to manage the pain? Should I create a birth plan?

Ask away! Feeling prepared can help calm your nerves before delivery.