But not all procedures that appear to be high risk are officially designated as such, including vaginal delivery. Giving birth vaginally isn’t considered a high-risk or aerosol-generating (meaning healthcare workers are at a higher risk for contracting infection) procedure by the World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC). As a result, PPE like N95 masks aren’t recommended for labor and delivery staff. A new study from UCLA, published in the journal Obstetrics & Gynecology, found that respiratory emissions during labor and delivery can travel faster—and potentially farther—than a simple cough, thereby increasing the risk of respiratory disease transmission (such as the COVID-19 virus). “Prior to this study, there was no data regarding respiratory emissions during a vaginal delivery and thus recommendations regarding PPE use were limited to opinion,” says Rashmi Rao, MD, assistant clinical professor of obstetrics-gynecology at the David Geffen School of Medicine at UCLA and corresponding author of the study.
What the Study Found
Colleagues in the UCLA Samueli Mechanical and Aerospace Engineering Department studied respiratory emissions using background-oriented schlieren imaging. This technique relies on measuring or visualizing shifts in focused images, and in this case, it made the flow of invisible warm gases and cooler surrounding air visible. Labor and vaginal delivery also involves repeated use of the Valsalva breathing and pushing technique. This creates increased emission of respiratory particles, which move with great speed over a large distance and stay suspended in the air. The researchers found that during active labor, complex gas clouds (i.e. respiratory emissions made up of gases and particles) can travel at an average speed of 1.8 meters per second, which is about 30% faster than a gas cloud travels during normal breathing and at least 6% faster than gas clouds produced when coughing. Given the spread of these respiratory emissions, the speed and distance the particles travel, and the duration of time healthcare providers spend assisting in a vaginal delivery, the researchers believe that this is a healthcare setting at high risk for respiratory disease transmission. “With this study, we can begin to reevaluate the recommendation and support the use of full PPE with N95 masks for a vaginal delivery,” Dr. Rao says.
The Reality of the Labor Ward
Iris Colon, MD, an OB/GYN with Santa Clara Valley Medical Center in San Jose, California, welcomes the findings for labor and delivery healthcare practitioners. “These findings are important, as they provide evidence from a dedicated study on respiratory emissions during labor. [It shows that] the process is one in which labor and delivery staff are exposed to respiratory emissions in a close contact situation and [for] a prolonged period of time,” she says. Dr. Colon adds that the study highlights and provides evidence of what OBGYNs know from many years of taking care of patients in labor. “Namely, [we know] that the labor and delivery process is a high-contact and high-exposure event, and as such, practitioners need to protect themselves,” she explains. In fact, Dr. Colon and her colleagues used PPE during vaginal and cesarean deliveries even before the COVID-19 pandemic. It is for their safety and ability to remain healthy enough to provide care for their patients, she says. Not providing full PPE to labor and delivery staff simply isn’t an option, Dr. Colon adds. “If there is a shortage of PPE, then we need to teach staff how to safely reuse [what is available],” she says. If you’re pregnant and worried about giving birth during the COVID-19 pandemic, ask a healthcare provider to talk you through the process. You can opt to wear a mask, if it is not already required at your hospital, and/or request that the providers assisting in your labor and delivery also wear PPE. Hospital staff will be able to answer your questions about the labor and delivery process and the steps the hospital takes to reduce the risk of COVID-19 transmission.
