Group B Streptococcus and First Trimester Miscarriage

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Pregnancy is a very delicate point in a woman’s life because anything that affects the mother is passed directly to the baby inside her womb. Thus, laboratory tests are conducted to ensure the good health of both the mother and the baby. A culture test for Group B streptococcus (GBS) is often done during the 35th or 37th week of pregnancy. This type of bacterium is responsible for certain complications during pregnancy and delivery that is why it is necessary to detect its presence as soon as possible. However, several symptoms that are attributed to this bacterial infection can be experienced as early as the first trimester of pregnancy. In such case, prompt medical attention must be provided to the pregnant woman to prevent serious health hazards.

GBS is a type of bacteria that normally live in the intestinal and genital tracts of a person; they do not usually cause harm, unless an overgrowth or colonization in the bloodstream occurs. This condition, if present in pregnant women, can cause preterm delivery, urinary tract infections, endometriosis, and still births. According to a study made by Dr. Renee D. Stapleton, a professor at the University Of Washington School Of Medicine in Seattle, African-American women, health care workers, and overweight women are faced with an increased risk of being GBS carriers during pregnancy.

Group B Streptococcus: A Threat to Normal Pregnancy

GBS is a naturally-occurring bacteria located in the genital tract, the bladder, rectum and throat. The colonization of these bacteria occurs in the mucous membranes of a person, and transmission of GBS is done through sexual contact, touch, or breathed in the air.

In July 2003, Dr. Harald Leitich and his colleagues from the Department of Obstetrics and Gynecology in the University of Vienna made a study regarding the relationship between bacterial infection and preterm delivery. The result of this study that was published in the American Journal of Obstetrics and Gynecology stated that women who have bacterial infection in early pregnancy, such as bacterial vaginosis are nine times more likely to have a miscarriage, as compared to uninfected women.

The Center for Disease Control and Prevention (CDC) in Atlanta, Georgia, stated that pregnant women have an increased risk of having babies with GBS infection if they have one of the following:

  • Fever during the time of labor
  • Previous babies who have diseases linked with GBS
  • Water breaks 18 hours or more before delivery, or if labor occurred before the 37th week of pregnancy
  • An infection in the urinary tract that is associated with GBS

GBS causes infection in the blood, the lining in the brain and the lungs of the unborn baby. Therefore, GBS can potentially harm the baby, resulting to miscarriage or stillbirth.

GBS Infection and Chorioamnionitis

GBS infection can occur at any point during pregnancy; and such medical condition can lead to Urinary Tract Infections, postpartum infections, and chorioamnionitis (an infection of the placental tissues). Among the three illnesses, chorioamnionitis poses serious complications to the mother, such as labor abnormalities, bacteremia, and heavy blood loss during delivery. Babies who are delivered from mothers with chorioamnionitis are likely to develop pneumonia, meningitis, bleeding in the brain, and respiratory distress syndrome. Fetal death is also likely to result from this medical condition, and some women suffer from miscarriage as early as the first trimester because of this severe infection of the placental tissues.

Although GBS infection is one of the causes of chorioamnionitis, the presence of other bacteria can be attributed to it, such as E. coli and anaerobic bacteria. Symptoms of a bacterial infection include high fever, rapid heartbeat, profuse sweating, vaginal discharge with an unusual odor, and a uterus that is tender to the touch (confirmed during a physical exam). Early detection of bacterial infection must be done for prompt treatment.


Bacterial Vaginosis as a risk factor for preterm delivery: A Meta-analysis, From

Infections in Pregnancy: Chorioamnionitis, From