A Boston-based study published on Nov. 18 in JAMA Pediatrics suggests that phthalate exposure may play a role in preterm birth risk. The research has put commonly used household items in the spotlight.
Phthalate (THAL-ate) is a chemical found in everyday plastics as it is used to soften PVC. From nail polish and vinyl, to toys and the plasticware used in food storage – all contain this softening agent. Officially, the health risks of phthalates are largely unclear as stated by the Food and Drug Administration.
In this particular study conducted from 2006 to 2008, 130 women who delivered before their full term of 37 weeks were compared to 352 women who delivered full term babies. The pregnant women’s urine was sampled up to three times throughout their pregnancies and measured for phthalate level.
The study found that preterm birth risk was two to five times higher in the women whose phthalate level in urine was highest compared to those women whose phthalate level was lowest. Furthermore, in the case of spontaneous birth, where no medical condition is found to cause the early delivery, the correlation between phthalate level and preterm birth risk was even higher; there were 57 such cases of spontaneous preterm deliveries within the study.
“These data provide strong support for taking action in the prevention or reduction of phthalate exposure during pregnancy,” said the researchers.
Phthalates have been targeted in recent studies linking them to other health problems such as Type 2 diabetes and obesity in African-American children. Studies also associate a higher diabetes risk in women due to phthalates found in cosmetics like nail polish.
While other studies in the recent past have looked at maternal age and reproductive assistance as factors in the rise of preterm births, a large percentage of the rate increase, about 50%, could not be explained according to Shanna Swan of Icahn School of Medicine, Mt. Sinai, New York. In an editorial published with the new research findings on phthalates, Swan says the study might “contribute significantly” in understanding the gray areas that cannot be attributed to other preterm risk factors like maternal age.
While this study only shows a possible link between phthalate exposure and preterm birth, researchers do ponder on the nature of the role phthalates may play to cause preterm delivery.
Some lab studies have shown phthalates to cause inflammation. While the chemical’s inflammation effect on humans is yet to be determined, researchers speculate that phthalates could cause inflammation of the uterine lining leading to preterm birth. Immune response and hormone imbalances are other areas in which phthalate’s role is suspect.
“This finding may be dramatic but women should not be alarmed,” said Dr. Thomas McElrath of Brigham and Women’s Hospital (Boston) and co-author of the study, in a press release.
Phthalates occur naturally in food like milk, butter, grapes, and meat. Increasingly, however, phthalate chemicals are found in many non-edible personal items like cosmetics, deodorants, perfumes, and shampoo. While researchers are not recommending any broad changes in prenatal care based on their findings, they do suggest a simple avoidance of phthalates, found in personal items and plastic food containers, may downplay their possible role in preterm birth risk.
By Fatema Biviji