In my opinion, culturing every laboring woman for MRSA is unwarranted, because there is no evidence that such a program is necessary. Micro-organisms and humans have historically coexisted. Methicillin-resistant Staphylococcus aureus (MRSA) was first recognized in the 1960s and became endemic in many hospitals by the 1990s. The gram-positive bacterium, which is resistant to antimicrobial agents such as penicillins, cephalosporins, and carbapenems, can be present in or on the host without tissue invasion or damage. This is referred to as colonization. MRSA can cause infection by entering the tissue or sterile body fluid of the host and can cause boils, abscesses, or systemic infections such as osteomyelitis and bacteremias.

MRSA in obstetrical cases was studied recently, showing a 0.5% incidence in 2,963 participants in one study (Chen, Huard, Della-Latta, & Saiman, 2006) and a rate of 3.5% in 5,732 women in another study (Andrews et al., 2008). Some studies, however, have questioned the clinical relevance of MRSA-positive colonization. The effect of MRSA colonization on the mother was reported by Robicsek et al. (2008), who found that MRSA screening resulted in no significant decrease of MRSA among obstetrical patients in the observation phase, when they were screened for MRSA in intensive care units, or during universal screenings administered at the time of their hospital admissions. In the study by Harbarth et al. (2008), 21,754 surgical patients were screened for MRSA, yet no significant differences in surgical site infections were associated with MRSA when standard infection control measures were utilized. One could postulate that similar results would be reported within the obstetrical population after a vaginal delivery or cesarean section.

Most pregnant women are considered a low-risk population; therefore, the benefit of an active screening program does not seem apparent at this time. Before aggressive screening measures for childbearing woman are implemented, evidence should be gathered about maternal and newborn colonization, transmission, infection, and outcomes.

Rather than use cultures for all laboring women, we should take the advice of Harbarth et al. (2008), who suggested that the best course of action is to interrupt the transfer of MRSA from a "reservoir" to a "susceptible host" to break the "chain of infection" and decrease the risk for colonization and infection through the use of basic infection control measures. The use of infection control measures in obstetrics dates back to the mid-19th century with Semmelweiss, who reduced the number of cases of childbed fever and associated deaths by having doctors and medical students wash their hands in a chlorine solution before and between each patient's examination. Other major factors in stopping MRSA transmission include using barriers (e.g., gown and gloves), cohorting individuals, conducting environmental cleaning, disinfecting equipment, and treating MRSA staff carriers.

Although infection control measures are necessary, an active screening program for MRSA among obstetrical patients is not. There may be a need to re-evaluate the implementation of active screening if further studies identify an increased incidence of MRSA within this population, but that has not been the case thus far.

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