A woman is suing her doctor after finding out she was seven months pregnant.

The 25-year-old Melbourne resident allegedly made four trips to her GP complaining of nausea but the doctor never referred her for a blood test.

She said she was quite distressed when she found out she was expecting.

"When the ultrasound guy said, 'Congratulations, you're 29 weeks pregnant', I just completely flipped out. I only had two months to work out what I was going to do, how I was going to look after him."

According to News Limited, she visited Dr Ruth Mitchell at her Carlton clinic in April and June of 2009 however the doctor said her symptoms were related to a middle-ear problem.

She was given a urine pregnancy test however it came up negative.

The woman said her son, now three, is a ‘charming’ little boy and the Supreme Court action is about providing him with the life he deserves.

"I've worked hard over the last three years to get my life in order so that I can give him the education and opportunities I want for him," she said.