A surrogate mother of two babies gave birth, later to discover one of the children was biologically hers.
In an unbelievable turn of events, Jessica Allen became pregnant with her own child when she agreed to become a surrogate to a Chinese couple.
Doctors first believed both children to belong to the couple and assumed they were twins, leading to both babies being handed over to the couple after being delivered.
Allen, who lives in California, USA, then had to fight to retrieve her biological son.
She told Newsday, "I was pregnant through IVF already and at about six, seven weeks they found another embryo and they labelled it that the one embryo that they transferred split and turned into twins.
"My body naturally still ovulated while I was already pregnant - that's very rare - no one really knows about it but obviously, with my situation, more people are learning about it.
"It's called superfetation - it has a medical term to it, so why this process is not explained to surrogates, I don't know. They don't give this as a possibility. "
Allen, who had two children before deciding to become a surrogate, didn't see the babies before they were given to the couple,
The new parents text a picture of the babies to Allen when they were a few weeks old and admitted they had doubts about the origin of one of the children.
"I immediately freaked out and I asked my case worker, 'what's going on, how can this be, what's happened, how did this happen?' and she didn't have any answers for me," Allen said.
"So she [the case worker] said the next thing we need to do is to get me to have a DNA test."
The intended mother took the baby for a DNA test, then asked Allen for a Skype call to discuss the results.
"That's when she announced that the results indicated that I was his genetic mother," she said.
"During the Skype call she did suggest that we could give him up for adoption and they already had a couple thinking about adopting him.
"At this point we had no idea what to do, so by the end of the call we told her we were going to talk about it, because we needed to figure out how we're going to get ready for a baby literally overnight."
But the next day, she contacted the intended mother and told her, "We definitely want our son."
Because the intended parents' names were on the birth certificate, Allen had to fight for her son.
"I'm not on his birth certificate but I am his genetic mother, my husband is his genetic father and we have that proof through DNA," she added.
Allen was asked to pay back part of the fee to the couple as she was paid more to carry two children, and they also incurred legal fees to fight for their son.
But the story has a happy ending. He was returned back to them and is now 10 months old.
The mum-of-three finished, "When she [the case worker] pulled him out of her car and walked towards me, I just snatched him from her and said 'give me my baby' and I was just kissing him and trying to look at his face for the first time.
"I sat in the back seat with him so I could see him and talk to him and stuff."
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