The United States 2016 election, when President Donald Trump was voted into office, may have been tied to a rise in premature births among Latina women across the US, according to a new study.
In the nine months beginning with November 2016, about 3.2% to 3.6% more preterm births to Latina women occurred above the levels of preterm births that would have been expected had the election not occurred, suggests the study, published in the medical journal JAMA Network Open on Friday.
Birth outcomes have long been used in medical research as indicators of acute stress among populations of women, and preterm birth in particular is linked with maternal stress, the researchers noted in their study.
“Because mothers and children are particularly vulnerable to psychosocial stress, our findings suggest that political campaigns, rhetoric and policies can contribute to increased levels of preterm birth,” said Alison Gemmill, an assistant professor at the Johns Hopkins Bloomberg School of Public Health in Baltimore and first author of the study.
The study showed only an association between premature births among Latina women and the election, not that the election directly caused any negative birth outcomes. To determine that, more research would be needed.
‘The relationship between hostile immigration climate and health’
The study involved analyzing monthly data on preterm births in the United States from January 2009 through July 2017. The data, which included 32.9 million live births total, came from the US Centers for Disease Control and Prevention’s WONDER online database.
In the study, a preterm birth was defined as a live birth before 37 weeks’ gestation, and the researchers took a close look at how many of those births occurred among mothers who identified themselves as Hispanic on their child’s birth certificate.
The researchers found that preterm births represented 11% of births to boys and 9.6% of births to girls among the Latina women, compared with 10.2% and 9.3%, respectively, among other women, between 2009 and 2017.
Boys are typically more vulnerable to maternal stress, Gemmill said, so the higher percentage of preterm births among boys “provides further support that the election could be viewed as a population stressor” among the women in the data.
The researchers used the data to calculate how many preterm births were expected to take place during that time period, between 2009 and 2017, if the political climate around the 2016 presidential election had been different. They found that, from November 2016 to July 2017, an additional 2,337 preterm births to Latina women were recorded.
“We observe this increase over and above expected levels of preterm birth in the general population, which has been increasing overall since 2014,” Gemmill said.
The study had some limitations, including that the researchers were unable to separate the data on Latina women to determine differences among those who were foreign-born versus those who were born in the United States, and only an association was found between preterm births and the presidential election – not a causal relationship.
“We think there are very few alternative explanations for these results. One possible explanation could be if there was a sudden change in the composition of Latina women giving birth around the time of the election,” Gemmill said. “A drop in the number of foreign-born women among all Latina women giving birth immediately after the election could have contributed to observed increases in preterm birth.”
Women not born in the United States typically have lower rates of preterm birth compared with women born in the US, but Gemmill added that a drop in foreign-born women still does not explain the difference in male versus female preterm births.
Additionally, since the study ended in July 2017, more research is needed to determine whether a rise in preterm births among Latina women has persisted over the last two years.
The new study “is an important and unique illustration of the relationship between hostile immigration climate and health,” but the concept that this association exists is not new, said Michael Kramer, an associate professor of epidemiology at Emory University’s Rollins School of Public Health in Atlanta, who was not involved in the study.
“Two things stand out to me about this finding,” Kramer said.
“First, Latina women are often described as having better pregnancy outcomes than we might expect given socioeconomic status,” he said. “So it is particularly noteworthy that we see a meaningful jump in preterm birth despite what appears to be Latinas’ resilience to other kinds of stress.”
Second, “in general, acute stressors have been seen to be less influential than chronic or long-term stressors. So the finding of an increase in preterm birth abruptly and in such a short time is notable,” he said.
A similar finding in New York City
The new study’s findings align with some previous research.
In New York City alone, the overall preterm birth rate significantly increased from 7% to 7.3% between the time before the 2016 presidential nomination and after the inauguration – with the most dramatic increase occurring among Latina women, according to a separate study published in the Journal of Epidemiology and Community Health in 2018.
That was the first research published on the association between preterm births and the 2016 presidential election, said Nancy Krieger, a professor of social epidemiology at the Harvard T.H. Chan School of Public Health in Boston, who was first author of that previous research but was not involved in the new study.
The new study builds on that previous research to provide a national snapshot of potential links between America’s social and political climate with preterm birth outcomes.
Get CNN Health's weekly newsletter
Sign up here to get The Results Are In with Dr. Sanjay Gupta every Tuesday from the CNN Health team.
“It’s really critical to think about the research results presented here because it’s not as if once you show there is an increased risk of preterm birth that the story is over,” Krieger said. “These children will now grow up. They will be impacted by the fact of having been a preterm birth baby.”
She added that the research is a reminder to be more mindful of how certain political rhetoric can impact others, for physicians to be aware of such stressors and for those experiencing stress or fear to share their experiences with their health care providers and loved ones.
“The worst thing you can do is to become isolated in your fear,” Krieger said.
“Yes there is an old adage: ‘Sticks and stones may break my bones but names will never hurt me.’ Actually divisive political rhetoric that is dehumanizing and that induces fear does cause harm,” she said. “It causes bodily harm and it’s a harm that can be transmitted from one generation to the next.”