Group B Strep neonatal infections is one of the leading infections in newborns, most of which are acquired by vertical transmission at the time of childbirth. Most cases can be prevented by identifying women who are colonized with GBS in the vaginal-rectal area and giving colonized women prophylactic antibiotics in labor. About 15-20% of women are colonized and nearly all of these women are asymptomatic. Because it takes up to 48 hours to obtain culture results, it is currently recommended to perform cultures in the clinic about 5 weeks prior to their due date and then treat those with GBS when they come in for labor. There are several downsides to this strategy. All women who present with preterm labor are treated until culture results become available (overtreatment); women who go into labor while waiting for culture results are all treated (overtreatment); prior studies have shown 33% of women are positive at 35 weeks, but negative at birth (overtreatment) and 10% are negative at 35 weeks and positive at birth (undertreatment); lost or missing culture results (over- or undertreatment). Using microfluidics and fluorescent PCR, a new test can identify GBS reliably in 30 to 45 minutes in vitro. This study proposes to evaluate the clinical performance (sensitivity, specificity, positive and negative predictive value) of the microfluidic rapid GBS technique in un-selected sequential women presenting to labor and delivery, comparing them to cultures taken at the same time and the 35-37 week cultures in these same women. We will also evaluate the identification of GBS before and after rupture of membranes (amniotomy) using both standard GBS culture and rapid PCR (HandyLab technology).