(2003-12-16) -- A Food and Drug Administration (FDA) panel has approved over-the-counter sales of the so-called 'morning-before' pill. Although experts disagree over how the pill works, it seems to prevent unwanted pregnancy by attacking the problem at its source in the human brain.

The drug is an emergency pre-emptive contraceptive known as "Plan A", which, when taken 48-72 hours before potential unprotected sex, is 100 percent effective in preventing pregnancy.

Rather than causing a quick abortion, like the so-called 'morning after' pills, Plan A works on the cerebrum in the brain to actually keep women from getting into sexual situations in the first place.

"It seems to knock some sense into them, clinically speaking," said one unnamed FDA researcher. "After taking Plan A, our test subjects intuitively understood what men were really thinking. They no longer believed the words 'I love you' when it was just an inducement to sexual activity. In fact, they avoided situations where they might be alone together with any man to whom they were not married."

Scientists continue to work on a male version of the drug, also known as the 'personal responsibility' pill.