At least 71 US troops have been killed so far in October, a toll US commanders have blamed on more perilous patrolling by US forces trying to stamp out sectarian militias and insurgents in the sprawling capital.
"General Casey has ordered a review of Operation Together Forward. US casualties are a grave concern but that is not driving the review," spokesman Lieutenant Colonel Christopher Garver said.
"The enemy is adapting and we have to make changes," he said.
US commanders launched 'Operation Forward Together' in August to rein in spiralling sectarian violence in Baghdad, seen as key to stabilising Iraq. Some 15,000 US troops are helping Iraqi forces in raids that have targeted specific neighbourhoods.
US military spokesman Major General William Caldwell told a news conference the “the violence is indeed disheartening.”
He said "In Baghdad alone we have seen a 22 per cent increase in attacks during the first three weeks of Ramadan as compared to the three weeks proceeding Ramadan," he told a news conference.
Violence
Meanwhile a deadly series of bomb attacks in three Iraqi towns marked another day of brutal violence that left scores of people dead as the fierce debate over how to prosecute the war gripped Washington.
The northern city of Mosul shuddered under 10 apparently co-ordinated attacks erupting at 20-minute intervals, including several suicide car bombs, mortar fire and small arms assaults against US-led forces and Iraqi police.
The bloodiest attack was a massive suicide truck bomb against a police station which local authorities say killed 11 and wounded 26, the vast majority of them innocent bystanders, but more blasts followed.
Police closed the entrances to the city and imposed a curfew following the 10 attacks, which took place over just three hours.
Two of the suicide attacks were against US forces, but there was no immediate word on military casualties.
Following the Mosul assault, another suicide car bomb detonated in another northern city, the oil hub of Kirkuk, killing 12 people and wounding 68 outside a bank in the ethnically divided town.
The bomber blew up his car at the entrance to Bab al-Aswad bank in the south of Kirkuk just as Iraqi soldiers were waiting to collect their salaries, said local police chief Brigadier General Adel Zine al-Abidin.
A large part of the bank building, two army vehicles and several nearby shops were set on fire by the blast.