Third-Trimester Exams and Tests - Topic Overview
Routine exams and tests
At each prenatal visit, you
can expect to be weighed and have your urine and blood pressure checked. Your
health professional will monitor your fetus's growth and position by measuring
the size of your uterus (fundal height) and feeling (palpating) your abdomen.
If your fetus is not in the head-down (vertex) position after 36
weeks (as confirmed by
fetal ultrasound), your health professional may try to
turn it gently from the outside (version). Version carries some risks, and not
all health professionals are skilled in this technique. For more information,
see the topic Breech Position and Breech Birth.
Late in your
pregnancy, your health professional:
- Is likely to check you for
group B streptococcus, which can cause severe newborn
illness, disability, or death. This is done by rubbing the vaginal and rectal
areas with a cotton swab. If you test positive for group B strep (or if for
some reason you are not tested), you will be treated with antibiotics during
- Will check to see how far the baby's head has dropped into
your pelvis. Close to delivery, you may be checked to see whether your cervix
has begun to stretch and open (cervical effacement and dilatation).
- May check you for
hepatitis B. If you test positive for hepatitis B
infection, your baby will receive the hepatitis vaccine and hepatitis B
immunoglobulin (HBIG) within 12 hours of birth.
Later in pregnancy, your health
professional may recommend an
- You are going to deliver prematurely. An
amniocentesis is commonly used to see whether the fetus's lungs are developed
enough for delivery.
- There is a concern about infection in the