The woman has been charged with manslaughter, with an alternative charge of manslaughter of a child, according to the Aftonbladet daily.
"Everything indicates a post-natal depression," her lawyer Frida Wallin said.
According to a witness report the woman stood for a while on the bridge before leaping over the railing onto the road below.
The mother and child initially survived the 12 metre fall but were taken to intensive care with serious injuries.
The baby boy died in a hospital a few days later.
The woman, who for a long while was kept in a medically induced coma, was taken into custody by police initially on suspicion of murder or alternatively manslaughter.
The woman broke her leg in the fall and is reported to be well on her way to a full recovery.
The trial is set to take place at Stockholm District Court on December 3rd.