Last spring, when the whole world went into hibernation to try to curb the spread of a new virus ravaging the planet, few people were able to look on the bright side. But a few months later, neonatologists in different parts of the globe noticed something unusual: Their hospitals’ neonatal intensive care units, or NICUs – where babies born early or babies who need medical care are nurtured to health – were much less busy than normal.
The same appeared to be true at UPMC Magee-Womens Hospital, noted Dr. Lara Lemon, research assistant professor at the Department of Obstetrics, Gynecology and Reproductive Sciences at the University of Pittsburgh.
To understand what factors contributed to the drop in preterm births that Lemon observed, she enlisted the help of a perinatal physician and researcher, Dr. Hyagriv Simhan, executive vice chair of obstetrical services at UPMC Magee.
In a paper published online in mid-February in the American Journal of Obstetrics & Gynecology MFM, Lemon and Simhan concluded that the incidence of preterm births during the coronavirus pandemic decreased compared to prior years, perhaps driven by a combination of changes related to COVID-19.
“If you told me a few years ago that a viral pandemic would lower the rates of preterm births, I would’ve never believed it,” said Simhan. “But across the country and in our own hospital system, the decrease was substantial.”
The researchers showed that at UPMC Magee, which is home to Pennsylvania’s largest NICU, the overall incidence of preterm deliveries decreased by 1 percentage point, from 11.1% of deliveries before the pandemic to 10.1% between April and November 2020. To put it simply, 54 more babies were carried to term compared to the year before.
The unexpected benefit, however, did not apply to all women equally. Decreases in the rates of spontaneous preterm deliveries, or births before 37 weeks of gestation, were limited to white women, women living in advantaged neighborhoods and those who delivered at non-outpatient care facilities.
The rates of spontaneous preterm deliveries in white women, for example, decreased from 5.6% to 4.7% before and after the pandemic, respectively, compared to 6.6% and 7.1% in Black women.
“Systemic disparities in health care outcomes are at play here, too, although their effect is a bit different from what we traditionally think of as systemic disadvantages,” said Simhan. “The COVID-19 pandemic did not increase the risk of premature births in minority and lower-income patients, but the unintentional positive effect was appreciated only by the population already at the advantage.”
There is no single explanation for the effect they saw, researchers say, but the finding is exciting and invites further investigation. Epidemiological, biological and social factors that can affect the rates of premature deliveries are complex and intricately intertwined.
“Obstetricians have long been trying to decrease the rates of preterm births, but it’s an outcome they had a hard time impacting,” Lemon said. “A preterm birth sets the child’s entire life course, and it can have a massive impact on their life.”