Pregnancy: 7 Common Third Trimester Tests

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7 Common Third trimester tests introduction

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During the last trimester of pregnancy your doctor may recommend that you have certain diagnostic tests. These tests are all safe and have been developed to ensure the optimum well-being of both mother and baby.

Listed are some of the most common tests women who are pregnant will given.

Fetal Development Pictures Slideshow: Month by Month

Group B streptococcus screening

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Group B streptococcus (GBS) is a type of bacteria that can exist in the female reproductive tract without causing symptoms. Up to 30% of healthy women can carry group B strep, and it usually does not cause problems. However, sometimes it can lead to serious infection of the bloodstream, infection of the placenta, or urinary tract infection. Group B strep can also have serious consequences for the baby, causing potentially life-threatening infections in the newborn, including meningitis, pneumonia, and sepsis. Testing is simple and involves taking a sample from the vagina and from the rectum with a cotton swab. The swab is cultured in the laboratory to determine if group B strep is present. If the test is positive, you will be given antibiotics during labor to reduce the chances of infection in the baby. The test is usually done between the 35th and 37th weeks of pregnancy and should be done in subsequent pregnancies even if you test negative in your first pregnancy.

Medically Reviewed by a Doctor on 4/14/2015

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Common Third Trimester Tests - Experience Question: Please describe your experience with tests you had during your third trimester of your pregnancy.
Common Third Trimester Tests - Group B Strep Question: If your group B strep test was positive during your pregnancy, how was it treated during labor and delivery?