Heavily pregnant Nicole Richie has signed up for an 18-month anti-drinking driver course, known as the SB 38 alcohol program. The program is for people who have been convicted of DUI more than once within a seven-year period. Nicole has been arrested twice for DUI, once in July 2002 and the second on December 11 of last year, when Nicole drove her car in the wrong direction on the Southern California highway. She was later sentenced to four days in jail and served a whopping 82 minutes. But mom-to-be Nicole told Diane Sawyer last month that she's given up all controlled substances. "No alcohol, no marijuana, no pills, nothing. No smoking around me," she revealed.