How COVID-19 Impacted Pre-Term Birth Rates in the United States

A new study led by Daniel Dench, an assistant professor in the School of Economics at the Georgia Institute of Technology, found that premature births from cesarean (C-sections) and induced deliveries fell by 6.5 percent during the first month of the Covid-19 pandemic and remained consistently down in the ensuing months. The research raises questions about medical interventions in pregnancy and whether some decisions by doctors may result in unnecessary preterm deliveries.

In effect, the study begins to answer a question that never could have been resolved in a traditional experiment: What would happen to the rate of premature C-sections and induced deliveries if women didn’t see doctors as often, especially in person, during pregnancy?

Stay-at-home orders during the pandemic had a side effect of reducing prenatal care visits by more than a third. Dr. Dench and his co-authors found that in March 2020 — when the World Health Organization declared Covid-19 a pandemic, sparking business closures and stay-at-home orders around the country — preterm births from C-sections or induced deliveries immediately fell from the forecasted number by 0.4 percentage points. From March 2020 to December 2020, the number remained on average 0.35 percentage points below the predicted values. That translates to 350 fewer preterm C-sections and induced deliveries per 100,000 live births, or 10,000 fewer overall.

“We know for certain that doctors’ interventions cause preterm delivery, and for good reason most of the time,” Dr. Dench said. “So, when I saw the change in preterm births, I thought, if anything changed preterm delivery, it probably had to be some change in how doctors were treating patients. It’s really about, how does this affect fetal health? Did doctors miss some false positives — did they just not deliver the babies that would have survived anyway? Or did they miss some babies that would die in the womb without intervention?”

Dr. Dench plans a follow-up study examining fetal death records from March 2020 to December 2020 to answer this question. If he finds no change in fetal deaths at the same time as the drop in preterm births, that could point to “false positives” in doctor intervention that can be avoided in the future.

The full study, “United States Preterm Birth Rate and COVID-19,” was published in the journal Pediatrics. It may be accessed here.