Paris Hilton has opened up about her experiences welcoming children via surrogacy and the steps she took to make impending motherhood “feel real.”

In an extra chapter of her autobiography, “Paris: The Memoir,” available exclusively in the upcoming paperback edition, Hilton shared her surrogacy journey, revealing that she wore a prosthetic baby bump so she could know what it “felt like to be pregnant.”

The media personality and her husband, Carter Reum, welcomed two children via surrogates last year. The couple announced the arrival of their son, Phoenix Barron Hilton Reum, in January 2023 and their daughter, London Marilyn Hilton Reum, 10 months later in November 2023.

“I wanted to know what it felt like to be pregnant, so I bought a prosthetic stomach and wore it around the house for the day,” Hilton wrote, according to Today, which obtained an early copy of the book.

“I know that sounds crazy, but I wanted it to feel real — even in just this small way,” Hilton continued.

“Feeling that weight on the front of me, running my hands over it, envisioning a whole life in front of us.”

Hilton wrote that she realized it was a “silly” idea to wear the fake bump by the end of the day, given that she would be holding her newborn soon enough.

“It didn’t matter that no one else could see that I was expecting,” the former reality star explained. “My emotional baby bump was real, it was precious, and I was so completely happy to know it was exactly where it needed to be, growing warmer and bigger every day.”

According to Hilton, while it may have appeared like a “mistake” that she and her venture-capitalist husband welcomed their son and daughter in the same calendar year, it was their plan all along.

The Hilton hotel heiress wrote: “The dream was to have a girl and a boy, born separately but at the same time, so they’d grow up as twins.”

The couple chose to use separate surrogates to carry their children. According to the American College of Obstetricians and Gynecologists (ACOG), there are many risks involved in implanting multiple embryos, including a higher risk of infant mortality.

Hilton called it “a real-life miracle” that both of her “angel surrogates” became pregnant within the same year.

However, she wrote it left her with double the worry and fear.

“I was afraid to breathe. It was like keeping your eye on two little baby birds in a nest — so fragile, so precious, and completely out of our hands,” she wrote.

Surrogacy, in which a couple’s fertilized embryo is implanted into the uterus of a third person — the surrogate — who then carries the baby, has become increasingly popular among celebrity parents.

It is used for many reasons, such as a person being unable to become pregnant due to their age or the pregnancy posing a danger to an individual’s health. Hilton shared in an interview with Glamour UK last year that she chose this particular path to motherhood because she was “scared” of childbirth.

She also cited her experience being drugged and touched in invasive ways at the abusive boarding schools she attended as a teenager as another reason she used a surrogate, stating that she was scared of “even being in a doctor’s office.”

The surrogacy industry was worth an estimated $14 billion globally in 2022, according to a report from CNBC published in 2023, citing data from Global Market Insights.

The cost of the surrogacy process can reach upwards of $150,000, Business Insider reported in 2021.