In Sumerian Mythology, Ninhursag - also known as Ninmah - is the daughter of Anu, and the half-sister of Enki and Enlil. (All three had different mothers). She first had several daughters with Enki, then a son, Ninurta, with Enlil, and then later on two sons with Enki: Dumuzi and Nergal (or Irrigal).
She was the 'Chief Medical Officer' of the Anunnaki mission on Earth. It was in that capacity that, together with Enki, she she would have been responsible for the creation of mankind, some 300.000 years ago. This earned her the title of Nin.Ti, meaning 'Lady-Life'.
She represents Mother Earth, the source of all life: from Ninhursag came the birth of the planets; she is usually seen wearing a leafy crown and holding a branch to indicate fertility.