Stillbirths “might actually be the dark side of this,” Dr. Been said. Researchers couldn’t measure stillbirths in the Dutch data set, because only live infants undergo newborn screening. If most of the missing preemies were actually stillborn, Dr. Been said, there would have to have been a huge increase in stillbirths — maybe three times the usual number, conservatively. No one has reported such a change so far.
At one hospital in London, a study showed an increase in stillbirths after the start of the pandemic (not the lockdown). This increase might have come from hidden coronavirus infections, the authors wrote, or from women’s reluctance to seek medical care during the pandemic. Studies in Nepal and India showed that mothers were less likely to give birth in hospitals in the spring, and that stillbirths increased in those countries. Further complicating the picture, Covid-19 itself may raise the odds of premature birth.
To find out how pandemic lockdowns affected preterm birth across different countries, the Dutch researchers have joined an international consortium of nearly 40 nations sharing data. Lockdowns might have been good for the health of mothers and babies in some places and not others, Dr. Been said, adding, “In general, we see that this whole pandemic seems to increase inequalities a lot.” The Dutch study even hinted that the drop in preterm births was limited to wealthier neighborhoods, although the result wasn’t statistically significant.
“Boy, did this affect people really differently,” said Jennifer Culhane, a senior research scientist in obstetrics and gynecology at Yale School of Medicine.
Dr. Culhane said the new study confirmed what she had been hearing from colleagues in the United States about lower preterm birthrates this spring. “Anecdotally, this is what we’re all hearing and feeling,” she said. In the absence of strong evidence in the United States, she and her colleagues have partnered with an insurance company to begin a large-scale study of how lockdowns affected premature births in this country.
She speculates that the lockdown’s effects might have depended on economic circumstances. For mothers who had the resources to work from home, “This could have a been a stress-reducing moment,” she said. For essential workers or those experiencing economic hardships, it might have been a different story.
“We see gross inequities in this country,” Dr. Culhane said. “My guess is that women that had no reprieve from rat-racy-type things had, actually, an enhanced burden of stress.”