Reuters reports that the 33-year-old woman, Taloa Foster, has been arrested for child endangerment after being suspected of drunken driving.
The Oklahoma Highway Patrol arrested Foster on Wednesday after witnesses saw her tumble out of her pickup truck on a rural highway near Ada, located about 80 miles (130 km) southeast of Oklahoma City.
Foster's 3-year-old twins were in the truck, and one of the children stood up on the seat behind the wheel, steering the truck about three blocks across four lanes of highway before crashing into an embankment, they said.
The Pontotoc County District Attorney filed a child endangerment charge for driving under the influence.
The mother told authorities the boy had unbuckled his seat belt and she fell out while trying to buckle him back in.
She was not immediately available for comment and no lawyer was listed on her online arrest reports.
The children were not injured in the incident, police said.