For the most part, there are some pretty major signs to being pregnant: a growing belly, occasional morning sickness, a new fondness for strange food combinations. But those symptoms didn’t come for 23-year-old Australian model, who reportedly had no idea she was pregnant until she actually gave birth.

In an interview with Australia’s 7 News, Erin Langmaid said she went into labor on October 29—without any clue she had been pregnant the previous nine months—while in her bathroom. She claimed she didn’t experience any pregnancy symptoms and had even been using contraceptive injections.

“I wasn’t showing obviously because I fit into everything,” she said. “It’s just really bizarre.”

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At first, on the day she gave birth, she started feeling ill. Then, just 10 minutes later, she had given birth to a healthy baby girl named Isla May—again, in the bathroom.

“I heard a scream and I ran in there and then I saw the little one and I thought, ‘Hang on, there’s two,'” Langmaid’s boyfriend, Daniel Carty, explained. But, according to Carty, he began to panic when he realized his newborn daughter had stopped breathing.

Carty called 000 (Australia’s version of 911) and the operator walked him through the steps to save his daughter’s life. Once at the hospital, medical experts confirmed that Langmaid had experienced a “cryptic pregnancy.” 

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We want to share with you our new little family member. Isla May was brought into the world on Tuesday night, she lived in mummy’s tummy for 9 months without letting us know. After an extremely tough few days both mother and daughter are perfectly well and ready to go home. The support of our family and friends is something that we will never be able to thank them enough for. To Erin the courage you have shown is something I didn’t think possible, you are an incredible person and will be an amazing mum. Now after a big week we look forward to life as a little fam with the most gorgeous new little addition and all the great things that come with that! Thanks for all the support it’s been amazing xx love the Carty fam

A post shared by Daniel Carty (@dan_carty) on Nov 1, 2019 at 12:48am PDT

Wait, what exactly is a cryptic pregnancy?

So, a cryptic pregnancy (aka, a stealth pregnancy), is when a woman doesn’t realize she’s pregnant, Felice Gersh, MD, an ob-gyn and founder/director of the Integrative Medical Group of Irvine, in Irvine, California, tells Health. This can be for a variety of reasons: She may be asymptomatic, she may receive a false negative pregnancy test, or she may simply assume it isn’t an option due to fertility issues or age, says Dr. Gersh.

However, Dr. Gersh specifies that most cryptic pregnancies occur in overweight women who have very irregular cycles, “so they assume when they miss periods that it’s just who they are.” Also, they simply don’t recognize the growing baby within them, says Dr. Gersh.

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In the case of the Australian model, Dr. Gersh points out that she claims she was using contraceptive shots—which stop menstrual cycles—so not getting a period was what she expected. “She just didn’t conceive of the possibility that she was pregnant,” she explains.

Another uncommon characteristic of Langmaid's pregnancy: She apparently didn't gain much (if any) pregnancy weight. "Although she was thin, she apparently didn’t notice nearly a 7.5 pound baby within her,” says Dr. Gersh. She notes that this is “uncommon” but “not impossible,” due to the fact that with women who are young and have strong abdominal muscles, “the baby is held tightly to their body, as if in a binder.”

“It is unusual for a full-term baby to be unsuspected in a thin woman, but when the persons with her and she herself have no idea that pregnancy is a possibility, the signs are simply missed,” she explains.

Dr. Gersh does point out, however, that any woman who is pregnant can easily be recognized as being pregnant by a medical doctor, assuming one does an examination. “The pregnancy is cryptic to the woman as she is not suspecting she is pregnant, not because it can’t be detected.”

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