The beeping vibrato of pressure monitors, mechanical rhythm of the blood pump, low hum of the oxygenator and metronomic beat measuring heart rate: These are the sounds that emanate from a complex circuit of pumps, tubes, filters and monitors called ECMO, or extracorporeal membrane oxygenation. ECMO moves blood outside of the body through cannulae, or tubes, to an oxygenator that provides a gas exchange in the blood, removing carbon dioxide and replacing it with oxygen. The oxygenated blood is then warmed to the appropriate temperature and returned to the body using rhythms that mimic a beating heart.

When disease or trauma prevent the body from performing these life-sustaining rhythms, ECMO can take over.

In mid-March 2020, Marta Perez, MD, left her Florida-based private practice in obstetrics and gynecology to return to Washington University School of Medicine and Barnes-Jewish Hospital. Perez had completed her obstetrics and gynecology residence at those institutions, and now her husband, Michael Chomat, MD, was finishing a pediatric cardiology fellowship at the School of Medicine and St. Louis Children’s Hospital, and about to begin a pediatric intensive care fellowship.

Perez welcomed the move because it provided her with the opportunity to change the focus of her career. Rather than continuing in private practice, she wanted to return to academic medicine and focus exclusively on obstetrics. Now, working as an academic laborist, she serves as a hospital-based obstetrician who helps women deliver their babies and teaches residents and medical students about obstetrics.

Two factors in the timing of the move to St. Louis would prove to be extraordinary—for the world and for Perez. First, by early spring 2020, the scope and severity of a new coronavirus became evident worldwide, resulting in a pandemic. And second, Perez had learned she was pregnant with her first child, about to face many of the challenges and uncertainties her pregnant patients were facing.

When a new mother with high blood pressure is sent home with her newborn, she leaves the hospital with instructions to return—or visit her doctor—for a blood pressure check within the first 72 hours after discharge from the hospital. And she must repeat that visit seven to 10 days later.

Some pregnant women have high blood pressure, or hypertension, at the time of conception; others may develop it during pregnancy as a symptom of preeclampsia or eclampsia. In any case, it’s vital for these women to continue to monitor blood pressure after labor and delivery. Left unchecked, high blood pressure can cause headache, fluid retention and nausea, as well as organ damage, stroke and worse. Worldwide, hypertension is the second leading cause of maternal mortality, according to the World Health Organization.