It comes as no surprise that pregnant women — as well as the rest of us — should avoid ultra-processed foods that are loaded with unhealthy fats, excess salt and sugar, and a slew of colorings, preservatives, texturizers, and other additives that Mother Nature never put into whole, healthy foods.

But there's a new twist from researchers at the University of Washington.

In a study published in the journal Environment International, they're sounding an alarm about the dangers posed by the phthalates in the plastic packaging that most highly processed foods come in.

It turns out that phthalate-containing plastics can leach into food from the wrapping and packaging and even from plastic gloves worn by fast-food handlers. The phthalates then travel through mom's bloodstream into the fetus's circulatory system.

There, they increase the risk for everything from low birth weight and preterm birth to disorders such as autism and ADHD.

The researchers tracked more than 1,000 pregnant women for five years and found that, on average, ultra-processed foods made up more than a third of the participants’ diet. Every 10% greater amount of ultra-processed foods that a pregnant woman ate led to a 13% higher concentration of one of the most common and harmful phthalates in a pregnant woman's urine.

To protect your fetus and yourself, the smart move is to stick with minimally or unpackaged fresh fruits and vegetables and whole grains, and to avoid plastic-packaged desserts, treats, and prepared meals, either fresh or frozen.