New data shows that premature births have risen in the United States after years of decline
Premature births, after years of steady decline, rose sharply in the United States between 2014 and 2022, according to recently published data from the Centers for Disease Control and Prevention. Experts said this shift may be partly a result of the increasing prevalence of health complications among mothers.
“I’m not very surprised that these are the changes we’re seeing,” said Dr. Nahida Shakhtoura, chief of the division of pregnancy and perinatology at the Eunice Kennedy Shriver National Institute of Child Health and Human Development. “We know that maternal complications have been on the rise over the same time period.”
Births before the 37th week of pregnancy increased by 12%, although there were fluctuations during the pandemic years, with slight declines in 2020 and 2022. Births at or after 40 weeks decreased during the study period. The increases in preterm birth rates were similar across races and age groups, but the biggest jump was among mothers age 30 and older.
It’s the opposite of promising trends before 2014, when premature births were steadily declining and full-term births were on the rise. Although the latest report does not address the causes, it is “worrying,” according to Dr. Shakhtoura, especially since premature babies generally face an increased risk of developing health complications.
One reason for the rise may be that women are having children later in life, said Dr. Vanessa Torbinson, an obstetrician and gynecologist at the Mayo Clinic in Minnesota. She added that advanced maternal age represents an increased risk of health complications that may require early induction. Overall rates of high blood pressure in particular have been rising in recent years. According to the Centers for Disease Control and Prevention, nearly 16% of women who gave birth in hospitals had some type of high blood pressure disorder in 2019, and these problems were most common among women 35 and older. Rates of gestational diabetes have also increased, especially among older mothers.
In general, “the further along you are in your pregnancy, the greater the chance that the baby will survive,” says Dr. Donette Lewis, director of Northwell Health Maternal Medicine and a maternal-fetal medicine specialist. Studies have found that a baby born at 23 weeks, for example, has about a 55 percent chance of survival, with the chances increasing every week after that, Dr. Lewis said. The American College of Obstetricians and Gynecologists recommends inducing labor at or before 37 weeks if medically necessary.
Dr. Lewis said the most recent CDC data is “surface scanning.” One of the many unanswered questions is why there are so few differences in preterm birth rates between races, given that research consistently shows that rates of preeclampsia and high blood pressure are disproportionately higher among black women. She added that understanding who was incited and why may shed some light on this question.
Dr. Lewis said that despite concerns about delayed maternal age, many health risks can be managed. “Anyone considering pregnancy, regardless of age, should see a healthcare practitioner so they can be evaluated and, if any medical condition is present, so they can get it under control before trying to get pregnant.”