Premature births dropped during lockdowns in the early months of the COVID-19 pandemic.
A groundbreaking study, which included a group of mostly high-income countries — including the United States, Belgium, Canada, Chile, Denmark and Switzerland — found there were about 4% fewer preterm births than would have been expected in spring 2020.
That's nearly 50,000 babies not born early in just one month alone, The New York Times reported.
“This is a unique natural experiment, where the whole world experienced this pretty drastic lockdown at the same time,” said one of the study leaders, Meghan Azad, an associate professor of pediatrics and child health at the University of Manitoba. “So, it was a neat opportunity to look at what that might mean for maternal-child health.”
The study was inspired by the observations of doctors in places like Denmark, where numbers of the smallest preemies were down by 90%, and Ireland, where early births dropped by 75% or more, the Times reported.
Authors of an Irish study wondered if lower stress, reduced air pollution or exposure to fewer viruses and bacterial infections in lockdown might make a woman less likely to delivery early. The causes of preterm birth remain elusive.
Azad wondered if doctors were seeing fewer premature births that spring because some of those babies were lost to stillbirth or miscarriage, the Times reported.
Soon, more than 100 scientists, including Azad, were studying this phenomenon.
“It was this kind of crazy time,” she said. “A bunch of researchers had a lot of time on their hands, because their projects were slowed down or their conferences were canceled.”
The researchers used data covering 52 million births between 2015 and 2020. They focused in on data sets that covered an entire country or entire region of a large country to avoid skewed data for individual hospitals that might have fewer preterm births because of COVID-related diversions, according to the Times.
The study ended up including 18 high- and upper-middle-income nations.
It found that preterm births dropped by an average of 4% in the first and second months of the lockdown.
As lockdowns loosened and country guidelines varied, the drop in preterm births was gone by the pandemic's fourth month, the Times reported.
While the study authors found small increases in stillbirths in Brazil and Canada during some of the months, it wasn't enough to explain the overall decrease in preterm births, Azad said.
“The causes of preterm birth have been so elusive, despite considerable efforts,” said Dr. Denise Jamieson, an obstetrician at Emory University School of Medicine in Atlanta, who was not involved in the study.
“I think any reduction in preterm birth is noteworthy and important,” Jamieson said. “The next step is to really look at the why.”
That answer may vary, depending on a person's circumstances during the pandemic. Much is still unknown.
“Even if there are 52 million births in the study, it is not going to immediately answer all the questions,” said co-author Dr. Roy Philip, a neonatologist at University Maternity Hospital Limerick, in Ireland. “But at least this should trigger people to look more closely at what is ideal during pregnancy.”
In one example cited by the Times, Massachusetts lawyer Elizabeth Decker quit her job to stay home during her last trimester of her stressful second pregnancy. While her first child was delivered preterm, this second baby was born a week after her due date, according to the paper.
Decker had spent that last trimester during lockdown resting and sleeping as her husband taught school online and cared for their toddler.
“I was able to really not do anything for the last three months of my pregnancy,” said Decker, 36, who noted her blood pressure didn't spike until a week after her baby's due date.
Although Azad said she would have liked to have studied the reasons for this drop in early births, she lacked funding to continue, and other projects deferred early in the pandemic took over, the Times reported.
In spring 2020, people had “this burning desire to do something, to either help the pandemic or make something of it,” Azad said.
“We don't all have that extra time anymore,” she added.
The study findings were published online Feb. 27 in the journal Nature Human Behaviour.
The U.S. Centers for Disease Control and Prevention has more on COVID-19 and pregnancy.
SOURCE: The New York Times