Kovarian
The Eye Patch Lady was a mysterious woman of whom Amy Pond had recurring visions. She wore an eyepatch or a similar device over her right eye.
The first time Amy saw her was when she appeared at the little girl's bedroom door at Graystark Hall Orphanage. She appeared through a hatch in the door, which later disappeared. Amy was startled by the woman and asked who she was, but the woman ignored her and said "No, I think she's just dreaming". When Amy entered, the room appeared to be empty, with no evidence of the woman or the hatch. (DW: Day of the Moon)
While asleep on a pirate ship, Amy was woken by a noise and saw the woman in a hatch that opened on the hull of the ship. The woman said, "It's fine. You're doing fine. Just stay calm", and then she vanished instantly, along with the hatch. (DW: The Curse of the Black Spot)
Amy briefly saw the woman again while searching an acid mining factory for Rory Williams, though this time she did not speak. (DW: The Rebel Flesh)
She appears to be some kind of midwife, looking after Amy during her pregnancy whilst the Ganger Amy went with the Doctor. The Doctor deactivated the Ganger just as Amy went into labour. (DW:The Almost People)