Two women and the girl were killed in the suicide attack in Amiriyat al-Fallujah in Anbar province near the city of Fallujah, about 40 miles west of Baghdad, said the officials, speaking on condition of anonymity because they were not authorized to release the information to the media. A doctor at the hospital and her husband were among the wounded.
The attack follows a suicide bombing on Saturday that killed eight people and wounded 17 at a police checkpoint near Ramadi, which is also located in Anbar.
The violence comes two months after the U.S. handed control of the province over to the Iraqis and shows that militants have not given up the fight despite setbacks at the hands of U.S. and Iraqi forces.
Anbar, a predominantly Sunni Arab expanse stretching from the western edge of the capital to the borders of Syria, Jordan and Saudi Arabia, was long center stage of the war and a springboard for attacks inside Baghdad.
It was not immediately clear whether the Iraqi Cabinet was discussing the security deal, which has drawn sharp criticism from Iraqi Shiite clerics and Shiite-dominated Iran. The Cabinet must sign off on the agreement before sending it to parliament for a final decision.
Earlier Sunday, Syrian President Bashar Assad lashed out against the pact, saying U.S. troops contribute to regional instability and should pull out of Iraq as soon as possible.
Syria is Iran's closest Arab ally, and the U.S. has accused both of supporting insurgents - charges both countries deny.
Assad pointed to a recent American cross-border raid into Syria as evidence that the U.S. will use Iraq as a base to attack its neighbors.
"The latest American aggression on Syrian territory shows that the presence of American occupation forces constitutes a source of continuous threat to the security of Iraq's neighboring states and a factor of instability for the region," he said.
Iraq has asked the U.S. for an explicit ban in the proposed security pact on the use of Iraqi soil for attacks against the country's neighbors. The U.S. has replied to the request, but the details are not known.
The Iraqi parliament must approve the agreement by year's end when a U.N. mandate expires. Failure to approve the agreement or get the U.N. Security Council to issue a new mandate would force the U.S. to suspend operations in the country.