Bristol Palin, Sarah Palin

Bristol Palin has a difference of opinion with her famous mother, saying teen abstinence is "not realistic at all."

"Everyone should be abstinent, whatever, but it's not realistic at all," the 18-year-old mom said in an interview with Fox News' Greta Van Susteren, who pressed her on why.

"I don't want to get into detail about it," Palin said, before explaining that sex is "more and more accepted now... among kids my age."

She hopes other teens will learn from her story.

"You should just wait 10 years," she said. "It would just be so much easier."

Alaska Gov. Sarah Palin is a strong advocate of abstinence-only education, a position that drew attention and sometimes scorn when the family announced, soon after John McCain named Palin as his running mate, that Bristol was pregnant at 17.

One of the things teens can avoid by waiting to have sex is a very awkward talk with their parents. Palin said she enlisted the baby's father, Levi Johnston, and her best friend to tell Todd and Sarah Palin she was pregnant. But getting the words out, she said, was "harder than labor." Eventually her friend "blurted it out."

The 18-year-old described Johnson as a "hands-on dad," adding, "Eventually we'd like to get married."  

She also said she didn't regret the birth of 8-week-old Tripp, and that the decision was hers, not her mother's.

"I wish it would happen in like 10 years so I could have a job and an education and be like prepared and have my own house and stuff. But ... he brings so much joy. I don't regret it at all."

She added: "I hope that people learn from my story and just like — I don't know, prevent teen pregnancy, I guess."

What do you think? Are abstinence-only sex education programs realistic?