How is maternal GBS status assessed during labor?

Assessing maternal Group B Streptococcus (GBS) status during labor is primarily done through a swab test. This test typically involves collecting a sample from the vaginal canal and rectum, ideally between 35 to 37 weeks of gestation, although in some cases, it can be assessed upon admission to the hospital during labor. The rationale for this approach is to determine the presence of GBS, which can pose risks to the newborn if transmitted during delivery.

The swab test is highly specific and sensitive, providing reliable results that inform the clinician's decision-making regarding the necessity for antibiotic prophylaxis during labor. If a woman tests positive for GBS, she is generally advised to receive intravenous antibiotics during labor to minimize the risk of infection in the newborn. This proactive measure has been shown to significantly reduce the incidence of early-onset GBS disease in infants.

Other methods mentioned, such as ultrasound imaging, blood tests, or a physical examination, do not provide the necessary information specific to GBS status. Ultrasound is used for various assessments of fetal health and development, blood tests primarily evaluate other conditions, and a physical examination could provide general information about labor progression but not specifically about GBS. Therefore, the swab test is the appropriate