Preterm births fell during some Covid lockdowns, study finds

“The causes of preterm birth have been so elusive despite considerable effort,” said Dr. Denise Jamieson, an obstetrician at Emory University School of Medicine in Atlanta, who was not involved in the new study. Although the global study only found a decrease of about 4 percent, “I think any reduction in preterm births is remarkable and important,” she said.

“The next step is to really look at why,” added Dr. Added Jamieson.

dr Azad and Dr. Roy Philip, a co-author of the new paper and also the Irish neonatologist at University Maternity Hospital Limerick, who found a notable drop in very early births at his hospital in 2020, both said it was possible lockdowns had done it all different effects on different groups of people. A pregnant person like Ms. Becker, who was able to stay at home in a low-stress environment with good support, might have benefited. A frontline worker without health insurance might have had a different experience.

In this way, the results highlighted how much is still unknown about the causes of preterm birth. “Even though the study covers 52 million births, it will not answer all questions immediately,” said Dr. Philip. “But at the very least, this should encourage you to take a closer look at what’s ideal in pregnancy.”

The study also highlighted the unequal preterm birth rates across countries. In the five years of data, the United States had the highest preterm birth rate of any included high-income country — just under 10 percent. Finland’s rate, on the other hand, was below 6 percent.

The discrepancy is not surprising, said Dr. jamieson “Unfortunately, compared to other high-income countries, the United States is an outlier in many key maternal and child health outcomes.”

Future research could use this global dataset to study such disparities in maternal health. dr Azad said she originally hoped to study the causes of preterm births during lockdown, not just their frequency: were changes in air pollution correlated with changes in preterm births? What about hygiene, income or access to health care? But she lacked the resources to conduct further research, said Dr. Azad, and now these other projects that were postponed at the beginning of the pandemic have caught up with her and her colleagues.

dr Azad doubts that any of her tweets today could spark a major international research effort. Spring 2020 people have “this burning desire to do something, either help the pandemic or make something out of it,” she said. Some researchers even worked on the project for free. “I am a scientist; I don’t like using the word ‘magical’,” she said. “But it was kind of magical.”

Now the mysteries of preterm birth will have to await other investigators, said Dr. Azad, adding: “We all don’t have that extra time anymore.”