Maria del Carmen Bousada, who reportedly died Saturday, gave birth in December 2006 as a single mother after getting in vitro fertilization treatment at a clinic in Los Angeles.
The births ignited a firestorm of debate over how old is too old for a new mother, and how much responsibility fertility clinics have over who gets treatments.
Bousada told an interviewer she lied to the fertility clinic about her age, and maintained that because her mother had lived to be 101, she had a good chance of living long enough to raise a child.
Bousada's death was reported by the newspaper El Mundo and Diario de Cadiz. Cadiz is the southern province where Bousada lived her whole life.
Diario de Cadiz quoted her brother, Ricardo Bousada, as confirming her death but refusing to disclose the cause. The newspaper said she had been diagnosed with a tumor shortly after giving birth.
The Barcelona-based newspaper El Periodico de Catalunya quoted Ricardo Bousada as saying he sold the exclusive on his sister's death to an unidentified television program and that the proceeds would go to looking after his sister's twins.
The newspaper quoted him as saying that it had been "very difficult. Lately, she had been really bad." He could give no further details because of the arrangement, the newspaper reported.
The Associated Press was not immediately able to reach the brother for comment.
There was no word on who would raise the children, named Pau and Christian. Bousada had once said she would look for a younger man to help her raise them.
In January 2007, she told the British tabloid News of the World that she sold her house to raise $59,000 to pay for the in vitro fertilization.
"I think everyone should become a mother at the right time for them," Bousada said in a video of the interview provided to Associated Press Television News.
"Often circumstances put you between a rock and a hard place, and maybe things shouldn't have been done in the way they were done, but that was the only way to achieve the thing I had always dreamed of, and I did it," she said.
The retired department store employee said she told the Pacific Fertility Center that she was 55 — the clinic's cut-off for treating single women. She said the clinic did not ask her for identification.
Bousada lived with her mother most of her life in Cadiz. She hatched her plan to have children after her mother died in 2005, she said, initially keeping her plan secret from her family. When she finally told them she was two months pregnant, they thought she was joking.
"Yes, I am old of course, but if I live as long as my mom did, imagine, I could even have grandchildren," she said in the video.
Stories like this make me sad and mad all at the same time!