Powerful storms create a swath of economic and emotional damage, but do they also have lasting health effects? A new study shows that Hurricanes Katrina and Rita contributed to up to half of the stillbirths in the regions where the storms hit hardest.
Katrina “was a very stressful event for the people who were living in New Orleans and the outlying areas,” said Howard Mielke, a research professor in pharmacology at Tulane University and an author of the new study, published May 8 in the Journal of Epidemiology & Community Health. Mielke says he and his colleagues started to question whether what took place in the city had effects beyond the destruction, injuries, and deaths that were broadcast worldwide in late summer 2005.
Using city death records, they studied the risk of stillbirth in the damaged and undamaged areas for 28 months after the hurricane. In areas where as many as half of the houses were damaged, the risk of stillbirth was 40 percent higher than in areas that escaped the storm’s path.
For every 1 percent increase in the destruction of housing stock, the authors found, there was a 1.7 percent increase in fetal death. “Of the 410 ofﬁcially recorded fetal deaths in these parishes, between 117 and 205 may be attributable to hurricane destruction and post-disaster disorder,” they wrote. Mielke and his colleagues estimate that stillbirths accounted for 18 to 30 percent of all the deaths that occurred after the hurricanes.
The results surprised even the researchers. “It was a surprise that the stress created so much damage, so much fetal death taking place in the most flooded areas,” said Mielke. “The numbers line up in a logical progression, from the least damaged areas to the most, and to us, it was very convincing that there was a lot of stress-related fetal death.” After the hurricanes, things like food and water became difficult to find, with high heat and humidity aggravating the physical stresses that had an outsize effect on pregnant women and their still-developing babies.
Past studies have also pointed to ways in which the delicate nature of babies’ development in utero can be knocked out of whack by maternal stress during a disaster. Babies born to women pregnant during severe ice storms in Quebec in 1998 were more likely to be obese when they were five and a half years old and to have increased insulin resistance, which may lead to diabetes, as well as motor skill delays. An uptick in low-birthweight babies born in and around New York City after the attacks of Sept. 11, 2001, was also documented.
These studies show that health impacts will likely add to the terrible societal costs of severe storms, which climate models indicate will be more frequent and more intense with increased global warming.
“We knew there was a big storm coming, and some people could not get out of the path of the storm,” Mielke said. “Somehow, we just need to recognize that stressful events can have enormous impact on a developing fetus.”