Meredith begins the show as an intern and gradually progresses in rank at Seattle Grace Hospital throughout the series. Her voice can be heard narrating the program and she is best friends with Christina Yang.
Meredith Grey was born to Ellis Grey and Thatcher Grey. Her mother was a surgeon, which made family life difficult. She was also having an affair with one of her colleagues. Thatcher left when Meredith was 5 years old. Soon after, Ellis moved to Boston and Thatcher lost all contact.
In spite of excessive partying and drinking Meredith somehow graduated from Darthmouth college, but couldn’t hold down a steady job after. To get away from her mother telling her she had no ambition in life she travelled Europe with her close friend. However, she had to return home when her mother was diagnosed with early-onset Alzheimer's Disease. This spurred Meredith onto going to medical school, even though her mother had told her that she wasn’t cut out to be a surgeon. After she completed medical school, Meredith secured a position in the surgical residency program at Seattle Grace (her mother’s old hospital) and moved into her mother’s old house.
On the day before her internship began she had a one night stand with a man in a bar, he later turned out to be Derek Shepherd head of neurosurgery at Seattle Grace. She was shortly joined in her new house by two of her fellow interns Izzie and George and sparked a new friendship with Cristina Yang. She tries to hide the fact that her mother was the renowned surgeon Ellis Grey but the Chief of surgery recognises her at once.
Derek finally convinces Meredith to date him, and after convincing the other staff at the hospital that is wasn’t a bad idea things seem to be going steady. That is until Dereks estranged wife Addison starts working at the hospital. Derek struggles to choose between Meredith and Addison and eventually leaves Meredith with the simple reasoning that 'she's my wife.’
Devastated by Derek leaving Meredith seeks out her father, envisioning a wonderful family reunion, only to find out he has moved on and started a new family. She starts a series of one night stands, including George. This leads to him moving out and an end to their friendship. She finally starts dating her dog’s veterinarian, Finn Dandridge and Derek becomes jealous and angry. He criticizes Meredith’s choices and calls her a whore.
Derek divorces Addison and Meredith is faced with the choice between him and Finn. However, instead of choosing she decides to date them both. Derek finally manages to convince her to choose him after he tells her that he loves her enough to leave her. He decides that it is time that Meredith made a greater commitment to him and she leaves him, but they continue having “break-up sex” for weeks after. She decides she is ready to make the commitment to Derek but he has already moved on. Dereks relationship goes sour with Rose he and Meredith get back together. Rose does not take the break up well and she stabs him.
They move in together and plan a beautiful wedding, but they decide to give their ceremony to Izzy and Alex due to Izzy’s deteriorating condition. They instead write their marriage vows down on a post-it note. They came up with: 1. To love each other even when we hate each other, 2. To never walk away, 3. To take care of the other when they are old, senile, and smelly - 'this is forever.' She becomes pregnant with Dereks baby but laters has a miscarriage due to stress when there was a shoot out at the hospital. After trying again for another baby the obstetrician tells her she has "hostile uterus", this leads Meredith to think about other genetic flaws such as early-onset Alzheimer's Disease. Derek decides to start a clinical trial to cure the disease. Her best friend Cristina quits her job and her friendship with Meredith as she was nearly killed trying to save Derek’s life for her. She blamed Meredith saying that “if it was anyone else but you, I wouldn’t have done it”