A 35kg ovarian cyst has been removed from a woman who thought the growth was due to overeating.
Fairfax reports the cyst was discovered after Sharon Watt complained about stomach pains and the growth was removed last week.
Ms Watt is in Timaru hospital, but will likely be home for Christmas.
AAP reports she had no idea about the cyst and thought she had put on weight due to overeating.
"I can actually fit some of my clothes now, which is nice; I was wearing a 5XL T-shirt and I couldn't understand why," she said.
Gynaecologist Albert Makary told Fairfax the cyst, which weighs almost the same as 10 babies, was the biggest he had seen in his career.