About 10:20 a.m., one bomb detonated in the central al-Ghazl market, where another bombing on Nov. 23 killed 13 people.
Police and hospital officials told the Associated Press that at least 46 people were killed and more than 100 wounded.
One pigeon vendor told the AP the market had been particularly busy because it was a pleasantly crisp and clear winter day after a recent cold spell.
Ali Ahmed, who was hit by shrapnel in his legs and chest, said he was worried about his friend, Zaki, who disappeared after the blast.
"I just remember the horrible scene of the bodies of dead and wounded people mixed with the blood of animals and birds, then I found myself lying in a hospital bed," he said.
Emergency workers sifted through the bomb-blackened garbage-strewn site in search of a wallet, a watch, a piece of paper -- anything that could help identify the unrecognizable corpses, according to Agence France-Presse. A mobile phone lay amid the wreckage, ringing incessantly.
About 20 minutes later, a second female bomber exploded barely two miles away at the New Baghdad pet market. That blast killed as many as 22 people and wounded 65, according to police and hospital officials.
"We were just talking about the first bomb when it happened," said Abbas Muhammad Awad, 54, a pigeon seller. "There was not enough time for people to leave because it was only five or 10 minutes between the bombs."
In both bombings, women with mental disabilities wore explosive belts that were remotely detonated, Gen. Qasim Atta, spokesman for Baghdad's security plan, said on state television, according to CNN. The women's nationalities and identities have not been released.
Yahya Omran, 50, showed a New York Times reporter multiple scars from one of the previous bombs to strike that market. He complained that despite repeated requests the authorities had failed to erect a concrete blast wall to protect the market as had happened at other markets.
"I came back to work here because I have to pay rent and I need to support my family," he said. "I thought everything was starting to get better but then this happened. I think things are going to get worse. It's chaos."
Both markets are on the east side of the Tigris River, and both are in mainly Shiite areas. But they are popular with both Shiites and Sunnis.
The bombings were the most lethal blasts since Aug. 1, when three car bombs killed more than 80 people.
The attacks, which occurred shortly before the weekly Islamic call to prayer resounded across the capital, were the latest in a series of violent incidents that have been chipping away at Iraqi confidence in the permanence of recent security gains.
American military commanders have noted in recent months that in areas where there are many checkpoints, insurgents have begun using suicide vests instead of vehicles to carry out bombings because they are easier to sneak past road blocks and barriers, the Times reported.
Women in Iraq often wear a black Islamic robe known as an abaya and it can be easier for them to avoid thorough searches at checkpoints because of Islamic sensitivities about their treatment.
The number of Iraqi civilians and security forces killed in January fell to at least 599, an Associated Press tally showed, the lowest monthly death toll since December 2005, and continuing a downward trend since the fall. The figure as tabulated by Iraqi officials in the ministries of Defense, Interior and Health was slightly lower, at 543.
U.S. forces, meanwhile, have expanded offensives in central and northern Iraq, seeking to build on gains against al-Qaida in Iraq in the past year. But the latest campaigns also have driven up the military's death toll after months of decline.
Two U.S. soldiers were killed Thursday -- one by a roadside bomb in Baghdad and another by a rocket or mortar attack on a convoy support center south of the capital, the military reported.
The attacks raised to at least 39 the number of U.S. troops who died in January -- well above the 23 in December but still sharply lower than a year ago. In January last year, 83 soldiers were killed in Iraq.
