WASHINGTON — President Obama, noting that he was the father of two daughters, threw his wholehearted support on Thursday behind a decision by his health and human services secretary, Kathleen Sebelius, not to allow emergency contraceptives to be sold over the counter to young teenagers.

“The reason Kathleen made this decision is that she could not be confident that a 10-year-old or an 11-year-old going to a drugstore should be able — alongside bubble gum or batteries — be able to buy a medication that potentially, if not used properly, could have an adverse effect,” Mr. Obama said to reporters at the White House.

“And I think most parents would probably feel the same way,” the president added.

Mr. Obama insisted that he was not involved in the decision, on a contraceptive pill known as Plan B One-Step. The decision by Ms. Sebelius, announced on Wednesday, was an extremely rare case of an administration official’s publicly overruling the Food and Drug Administration, which had concluded after extensive research that the medication was safe to be sold to teenagers 16 and younger without a prescription.

The bluntly personal nature of the president’s response suggested that the White House is well aware of the political sensitivities, going into an election year, of allowing broader distribution of the contraceptive, whatever the Food and Drug Administration’s scientific arguments in favor of it.