Mirza, 35, had returned to tennis after giving birth to her son in March 2019 but her progress was later thwarted by the coronavirus pandemic.
Mirza made the retirement announcement after losing the Australian open women's doubles first round with partner Nadiia Kichenok.
"There's a bunch reasons for it. It's not as simple as 'okay I'm not going to play'. I do feel my recovery is taking longer, I do feel, considering my son is three years old, I'm putting him at risk by travelling so much with him, that's something I have to take into account," Mirza said at the post-match press conference.