Phthalates are found in food packaging and even some medicines, and now researchers believe the cancer-causing chemicals could also be linked to preterm birth.
"We know that exposure to phthalates is virtually ubiquitous in today's world. Rates of preterm birth are significantly higher now than they were several decades ago for unexplained reasons. In experiments with animals there have been studies showing phthalates may cause biological responses that may be relevant to preterm birth. The combination of these three things led to the hypothesis we studied here," Principle investigator John Meeker, associate professor of environmental health sciences and associate dean for research at the U-M School of Public Health, told Headlines and Global News in an email.
The researchers analyzed the urine samples of 482 pregnant women over the course of several months to test their Phthalate levels, a University of Michigan news release reported. About 130 women who were determined to have high levels of the chemical in their urine gave birth preterm.
"Preterm birth is a major public health challenge. Rates are significantly higher than they were 20 years ago and we don't know why. Other interventions have had limited effectiveness, and this helps shed light on a potential for environmental influences," Meeker said in the news release. "Next, we need to look at how pregnant women are exposed, and at what stage of pregnancy, to help inform exposure and risk prevention strategies."
The researchers are unsure why this connection exists.
"One possibility we are considering is that phthalates are causing changes in oxidative stress or inflammation in the mother, and that these changes are leading to early labor," Kelly Ferguson, doctoral student at the U-M School of Public Health and first author of the paper, said.
The researchers advised against jumping to conclusions too quickly, since further research is necessary in order to make a true causal connection.
"This is by no means the cause of premature birth, but it is a possible contributor- which is important because it is potentially modifiable," Doctor Thomas McElrath, a physician-scientist and key co-investigator on the study said in the news release. "This finding may be dramatic but women should not be alarmed. This is only the first step in a long research process that will be needed to clarify and confirm these results. It is simply too early to suggest making changes in prenatal care based on this study."
In the past, phthalates have been linked to a number of health issues in both male and female patients.
"Other research has shown adverse effects on male reproductive development, reduced testosterone levels in men, altered thyroid function in men and women, adverse effects on child neurodevelopment, and possibly increased risk of metabolic syndrome, diabetes, obesity, and other conditions," Meeker told HNGN.
