For the first time since her son Jett Travolta's death, actress Kelly Preston is opening up about her son's autism and what she believes caused his disorder.

Jett Travolta, Kelly Preston's son with actor John Travolta, died tragically in 2009 at the age of 16. He had suffered from a seizure and hit his head in a bathtub in the family's vacation home on the Grand Bahama Island.

Preston broached the subject on the CBS program "The Doctors". She blamed a number of factors for her son's autism. She said that her "fast and hard" labor was a culprit. She also blamed antibiotics that she took while breastfeeding, which gave her son thrush, a yeast infection of the membrane of mucus that lines the nose and mouth, which some have linked to autism spectrum disorder.

She especially mentions the Kawasaki disease that her son battled when he was younger. The disease causes inflammation of the arteries, particularly in children between the ages of two and five.

"[Jett] was autistic. He had seizures," Preston said on a taping of the show. "I strongly believe as a mother, as does my husband, that there are certain contributing factors that lead to autism and some of it is very much the chemicals in our environment and in our food...He was coming out of the autism, he really was."

The Travolta family was silent on the issue of their son's autism before his death, though John Travolta addressed it during a court trial afterwards. Many critics said that the family hid their son's autism because of their affiliation with the Church of Scientology. During an extortion trial after their son's death, John Travolta testified that his son had seizures every five to ten days, which would last a minute and after which he would sleep for 12 hours.

The episode also shows Preston touting the virtues of an organic diet, which she now follows with her daughter Ella, 12, and son Benjamin, 2. In the episode, she tours the factory of Alternative Laboratories in an effort to empower parents about living a life free of chemicals, she says.

Though doctors remain uncertain about the causes of the condition, most studies on autism spectrum disorder have linked it with various genetic factors. One famous study that linked autism spectrum disorder with vaccines has been thoroughly debunked.

The episode of "The Doctors" airs tomorrow.