(Reuters Health) - In the aftermath of an immigration raid, Latina women in the U.S. may be more likely to have low birthweight or premature babies even when they are citizens, a new study suggests.
To explore the link between immigration policy and pregnancy outcomes, researchers examined data on babies born before and after U.S. authorities arrested 400 undocumented workers at a kosher slaughterhouse and meatpacking plant in Postville, Iowa, in 2008. At the time, it was the largest single site raid in U.S. history.
“The Postville raid caused a great deal of fear and distress for immigrant and U.S.-born Latinos throughout the state of Iowa, including pregnant mothers,” said lead study author Nicole Novak, a researcher at the University of Michigan Population Studies Center in Ann Arbor.
“We know that emotional stress can affect pregnant mothers and their infants’ gestation in many ways, including shifting stress hormone balances in ways that affect a developing fetus,” Novak added by email. “Social support networks can help protect against these effects, but after the Postville raid fear isolated people from one another, reducing emotional support and leaving them doubly vulnerable.”
Pregnancy normally lasts about 40 weeks, and babies born after 37 weeks are considered full term. Babies who arrive earlier often have difficulty breathing and digesting food in the weeks immediately after birth. Preemies can also encounter longer-term challenges such as impaired vision, hearing and cognitive skills as well as social and behavioral problems.
For the study, researchers analyzed birth records for 52,344 infants born in Iowa either during the 37 weeks after the raid or in the same 37-week period the previous year.
Babies born to Latina mothers after the raid were 24 percent more likely to be underweight than infants born the year before, researchers report in the International Journal of Epidemiology.
Among foreign-born Latina mothers, 4.5 percent of newborns were underweight before the raid, compared with 5.6 percent afterwards. Among Latina mothers born in the U.S., 5.3 percent of infants were underweight before the raid, compared with 6.4 percent afterwards.
Premature births were also more common for Latina mothers after the raid, though this primarily impacted foreign-born women. Among Latinas born outside the U.S., 7.5 percent of infants were premature before the raid, and this increased to 8.9 percent afterwards.
But for white mothers, the odds of underweight or premature babies didn’t change significantly after the raid.
The proportion of white and Latina women getting adequate prenatal care, which can help reduce the risk of underweight or preterm babies, was little changed during the study period.
“This suggests that the effect of these raids on low birth weight is the result of psychosocial mechanisms such as stress or decreased social support rather than medical care use,” said Steven Wallace, associate director of the Center for Health Policy Research at the University of California, Los Angeles.
Because the adverse pregnancy outcomes extended to U.S.-born Latina mothers, this also suggests that the climate of fear in the aftermath of the raid impacted the entire community, not just immigrants, Wallace, who wasn’t involved in the study, added by email.
One limitation of the study is that researchers lacked data on where in Iowa mothers lived, making it impossible to know how much of the change in birth outcomes occurred closer to Postville, the authors note.
Even so, the results offer clear evidence of physical health problems that can result from stress experienced by immigrant populations, said Mina Fazel, a psychiatry researcher at the University of Oxford in the UK who wasn’t involved in the study.
“There is little benefit in raising levels of distress in any population, especially in those who already experience socio-economic deprivations, social stigma and little housing stability,” Fazel added by email.
Current U.S. policies restricting immigration by refugees and citizens of certain predominantly Muslim countries may also negatively impact birth outcomes, Fazel remarked.
“The increasing Islamophobia that these policy changes feed into in the U.S. is likely to have an impact on all Muslims in the country,” Fazel said.
SOURCE: bit.ly/2kgYF7D International Journal of Epidemiology, online January 23, 2017.
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