Sarah discovered her dad wasn't her biological dad. It was just the beginning.

When she was 27, journalist Sarah Dingle's mother told her - in a rather nonchalant way - that her father was not actually her biological father.

That, in fact, Sarah was donor-conceived with anonymous donor sperm.

At first, Sarah didn't believe her. She thought her mum was telling a joke; a weird, pretty off-colour and out-of-character joke, but a joke nonetheless.

"I made her say it several times because I couldn't take it in. And by the time she said it for, I don't know, the third time or something, I had to accept that I should pay attention to what she was saying," Sarah tells Mamamia.

"By the time I started to take it in, everything in the room went a bit strange, the sound went 'woooooo'. And I felt like I was about to faint or I'd sort of lost oxygen. It's one of those moments where, it's such a cliche, but the only word I can use to describe it is 'surreal'. And you start to go, 'Is this really my life?'"

What followed was a 10-year odyssey to find out who her biological father was - and ultimately expose the profoundly disturbing lawlessness of the fertility industry here in Australia. Sarah, who is now 39, wrote her experience in her book Brave New Humans: The Dirty Truth Behind the Fertility Industry and participated in SBS's documentary series Australia Uncovered.

Watch the trailer for Australia Uncovered Season 2. Story continues below.

Unlike some other donor-conceived people who feel they don't quite belong, Sarah had no inkling at all that her dad, who died when she was 15, was not her biological father.

"My mother's Malaysian Chinese. My father, that I thought was my biological father, was Anglo Saxon. I'm Eurasian; I don't really look like anyone. And when you're from two different cultures, you never feel like you quite fit anyway, so perhaps any sort of questions I might have had I just attributed to that," Sarah explains.

"I never questioned anything about my family. At all. Which is why it hit me really, really, really hard."

Sarah Dingle. Image: SBS.

After trying to find out more information from the fertility clinic where she was conceived, Sarah discovered that the donor conception codes, which contained information on who her biological father was, how many children had been conceived from his sperm and who these other children were, had been destroyed by the clinic.

Sarah would go on to learn that this practice was not uncommon, and that it is difficult to hold fertility clinics accountable due to the lack of clear regulations - then or now.

"There's no national laws. There's a set of guidelines, which clinics are supposed to adhere to - which they have not adhered to. And the other thing to say about those guidelines is that they're self-policing. So if you're not obeying those guidelines, the only organisation that is going to check up on you is the peer body for the fertility clinic," she says.

For anyone else, coming across a big hurdle like destroyed donor codes might have stopped them from proceeding any further - but not Sarah. Her journalist's brain would not let the issue rest.

As she investigated deeper, she made another startling discovery - her friend, Rebecca Ronan, who Sarah had met after Rebecca reached out as a donor child herself, was not just a friend: they were half-sisters. While they may not look alike, there are so many other things the two have in common.

Sarah and Rebecca. Image: SBS.

"I think I've struggled with it more than Bec has. There's absolutely no guidebook to this kind of thing, which is something people say often, but there really is no guidebook for finding out as an adult that you have many, many, many, many siblings, and you already know one of them," Sarah contends with a laugh.

"I think I flipped out and withdrew a bit at first because I was like, 'I actually don't know the significance of this'. I don't know how to behave. I don't know what I should do. And Bec's more of an extrovert, much more of an extrovert than I am anyway. We are [closer] but it's different too because our lives have changed since then."

Both Sarah and Rebecca now have children of their own. "And the weird thing is when we get our daughters together, once again, they don't look anything alike but they are the same person."

The half-sisters have also found other siblings. "It covers the whole range, so people that we know exist but we are not allowed to contact, people who we know are siblings and we've made contact but we have not met them, and then people who we know are siblings and we've met them," Sarah says.

"And there's more to come; there will always be more to come. I will, and Bec will, never have any sense, at any point in our lives, that we finally know the full extent of our family. We will just have random siblings popping up until the day we die."

Together with Rebecca, Sarah tracked down their biological father. In 2016, they found him. As it turned out, he had left a letter with the fertility clinic for any future children who might come looking for him.

"Yes, half of you came from me: your father wanted you but couldn’t get you, and it was I who did him the favour he needed most. Yes, I will let you know where that half of you came from. Yes, I will gladly meet you if that’s what you want. Yes, I will show you my life, and I will tell you about myself and my relatives. And I will always let you have any medical information you may need," the letter read.

The clinic had never provided the letter to Sarah, Rebecca, or anyone else.

After coming into contact with their biological father, the sisters agreed to meet up with him at a restaurant. Sarah recalls being understandably nervous.

"I have this thing that I do, where before I meet someone really important in my life, I get nervous and then I get lost and then I'm late," she says, laughing. "I was really late to meet Bec. I don't think I was quite as late to meet my biological father but yeah, I was really nervous walking into the restaurant."

Their first meeting may have been a little fraught, but Sarah maintains a good relationship with her biological father today. It is of course not the same as the one she had with her father; no-one will ever take his place in her heart.

Sarah as a child with her mum and dad. Image: SBS.

Given the struggle she went through to find her biological father and the abuse of power by fertility clinics, Sarah would like to see changes in federal law. And, in the absence of federal law, nationally consistent laws - currently, different states have different laws regarding donor conception.

"That is incredibly unfair. Why do you get to know your biological father if you're a donor-conceived person in Melbourne but not if you're donor-conceived of the same age in Hobart? Why are you judged as lesser and as incapable of having that knowledge?" Sarah says. She would also like records to be kept and held in perpetuity, rather than an "arbitrary period of five or 10 years, or destroyed at will".

"I want laws that implement minimum standards to uphold the basic human rights of the child... we're not asking for the moon or the sun or the sky; we're asking for basic human rights. The right to know your biological parents. The right to know who your biological siblings are so that you don't, I don't know, accidentally sleep with them!"

Accidental incest is something that Brisbane mother-of-five, Shannon, has thought about often over the years. Her children were all conceived via the same anonymous donor, starting with her eldest, Zac, almost 20 years ago.

Shannon, who is gay, had very limited options for donors back then because many men were not willing to father children for homosexual couples. As she recalls, she and her partner sat in a room with a geneticist, trying to see if they would be eligible for a donor. Shannon was 23 at the time.

"It was very much a case of, 'You tell us what you're looking for, briefly, like what would you say are your top three things. And then we'll see what we've got.' I told the geneticist first and foremost that my partner [at the time - the couple have since broken up] and I wanted someone who was willing to be identified when the kids were older because to us that was really important," Shannon tells Mamamia.

"And then we basically just tried to match characteristics of my ex-partner, along with the fact that 'sporty' to us was really important because I'm a very sporty person and also it's just a great way to meet people. It's a great life skill and it brings so much enjoyment."

Aside from that, Shannon asked for "medium skin" because she's got "your typical pasty English, Irish fair skin" and really wanted her children to have skin protection in the sunny climes of Australia. Blue eyes would be nice because her partner at the time had blue eyes and so did her mother.

The geneticist flicked through her book of donors.

"At that stage, donors could nominate whether or not they wanted to donate to lesbians, and many didn't. And so she came up with only two that she told us met that criteria. There was one who liked footy and surfing and was a sports administrator at a school. And that sounded really good to me because my parents are both teachers. And honestly, that was all the information we had. We didn't get to read the profile," Shannon says.

"I can remember trying to sort of look and her sort of pulling [the book] away a bit. I felt that it very much had the feeling of the 'under the table, we keep this information, we tell you only what you need to know'... I was very young. I just assumed that was the process. I certainly wasn't going to ask any questions because I was just grateful that we were given access, based on the fact we were a same-sex couple.

"So we just kept our mouths shut and did as we were told, and blindly trusted that everything was as it should be, and that the clinic knew all the rules and regulations. We were just grateful."

Listen to Mamamia's parenting podcast How To Build A Human. Story continues below.

It was only after Shannon had given birth to Zac that she began to gauge just how unregulated the fertility clinics were. She was at a daycare with her son and chatting with the owner when talk turned to donors.

"She said something about this other couple [who was also same-sex and had a child at the daycare] and how they had been certain that they were going to have a girl, which they were excited about, because their donor was a surfer so he spent a lot of time in the ocean. I don't know whether it's an urban myth or whatever that if men spend time in lower temperatures, they're more likely to produce girls. And I said, 'Oh, that's interesting. Because our donor liked surfing too'," Shannon says.

After comparing a few notes on the donor, it became obvious that there were a lot of similarities.

"It was just this huge, big punch in the stomach. Just the shock. I don't mean in a negative way. It wasn't positive or negative. It was just this penny dropping," she recalls.

"And I just went, 'Oh, my goodness.' And we just left it. We didn't say another thing about it. We just sort of both looked at one another. Both absolutely gobsmacked. Just not really game to talk about it any further. And then she said, 'Look, I'll go away and I'll talk to the girls and find out what their donor number was'."

The donor numbers did indeed turn out to match, meaning that little Zac had a half-sibling. Once she'd had time to process the news, Shannon decided it was a very positive outcome.

"You know, it felt like a really nice connection. Surreal, but after I'd gotten over the shock, I didn't feel any kind of threat by it. I just thought, 'Well, isn't that lovely?' And what a coincidence, small world. The other family, on the other hand, went the other way," she says.

"I've learned over the years that this is a very polarising issue for a lot of same-sex couples, because some really want to embrace the donor sibling factor. Others feel it threatens their nuclear family. And that ended up being the reason why they pulled [their little girl] out of care, and eventually moving away. And we have not had any contact with them or anything like that, which really hurt me. It really upset me at the time. I now have a much greater understanding of their perspective and their freedom to make that choice.

"I do wonder whether they'll ever tell their kids, because they had another set of twins after that, with the same donor. Everyone has their own views on the importance of that information. Some people feel it undermines the relationship of the mums. I have a different view. I just feel like it is that child's genetic information. It's factual. I don't think it does any good to hide it."

Shannon had always been intent on her kids knowing who their biological father was, once they turned 18. It was the one criteria she was adamant about when choosing a donor. Yet, years later, during some routine paperwork, she found out that the donor was not willing for any contact at all.

"We specifically wanted someone who was willing to be identified. I brought my son up literally saying to him, 'Look, okay, mate, you do have a biological donor.' He always had a curiosity about the male that he had come from. Whenever he would get upset about [not knowing who his biological father was], which kids do - they look at other kids and what they have, and they compare themselves - I'd always say to him, 'When you're 18, I will help you, I promise, we will track him down and you can find out who he is.' And that had appeased him, knowing that that was there in the future, even though he wanted it sooner," she says.

"So when he was roughly about 10, I then had to tell him, 'Mate, I am so sorry. But somehow there's been a mistake. There's been a dreadful, dreadful mistake'."

Shannon asked the clinic to contact the donor, to see if perhaps he had changed his mind in the intervening years. But they advised her they'd lost contact with him.

And that was that.

Well, almost. Like Sarah, Shannon is stubborn. She wanted to leave no stone unturned. So she signed up to a donor sibling registry website, where donor children can find each other and, if keen, get in contact.

A few years later, there was a match between Zac and a boy named Josh - they were siblings. Between Josh's mother, Jo, and Shannon, they actually managed to track down the donor father.

Shannon and Zac. Image: SBS.

"And it turns out, he is a tradie... Zac and I sat there together and phoned him," Shannon reveals. "We just wanted to hear his voice more than anything. I had no real plan. And Zac was very, very keen to hear him. Same as me. We were curious and wanted to know what he sounded like... And so I put it on speaker, and he sounded nice."

Not knowing how to approach the situation, Shannon made up a story about having a plumbing issue. "And he was beautiful. He was so helpful. And he was happy to come out and have a look for us. And that right there left me with the hugest ethical dilemma in itself."

Once off the phone, Shannon and Zac knew there was no way they could have him come over to the house. As much as they would have loved to have seen him in person, they could not trick him like that. 

"Ultimately, because more than anything, I owe my kids to this man. I have my children; there is nothing other than gratitude I feel. There is nothing I need. I would love some kind of contact for my kids. But again, if that was not something that he wanted, then I 100 per cent respect that. I can't change that. That's the decisions that he made," Shannon explains.

"I ended up calling him back and saying, 'Listen, I just spoke to you before. I have to come clean. I don't have a plumbing issue.' And he said, 'Oh, okay.' And I just kept talking. I just said, 'Look, okay, blah, blah, blah. I have five kids, and I think you're the donor.' And, at first, he just said, 'No, no', but he just kept listening. He kept listening to what I was saying. He didn't hang up. He didn't interrupt me. He just kept listening. So the more he listened, the more I spoke. And even though he protested at first, I just kept saying, 'Look, my kids are beautiful, and they are the best gift that I could ever have had. And more than anything I'm calling because I want to thank you for what you've given to me.'

"And then I started talking about Zac and how sporty he is because I knew that this fellow was, like, uber sporty, very, very sporty, just from the research that I'd done. He just kept listening."

Shannon told the man that the clinic made a mistake, in that she had always asked for a donor who would want to meet his kids one day, or at least be identified. She apologised for tracking him down. 

The donor admitted he'd done the donations when he was young, and hadn't given it much thought since. He had a seven-year-old child and had just started seeing someone. 

"It was just too big. I think for him, it was too big, you know? And I said, 'Look, I am never ever going to contact you again. I want nothing from you. And I completely respect whatever it is that you decide about this matter. I'm going to give me my number right now. And if you choose to contact us again, that would be great. But if not, then, you know, I wish you the very best. And the kids want for nothing. We're not looking for any kind of helping parenting - they have their parents. That's not what this is about. This is purely because the clinic made a mistake. And I needed to know, for my son, whether or not you still felt the same way that you did back then'," Shannon says.

It has been four years since that phone conversation, and Shannon has not heard from her children's biological father. She doesn't believe they ever will.

"And that's his decision. And there's nothing we can do about that. And that's fine. It's not what we would choose, but it's not his fault. He was given a set of conditions at that stage," she says.

"However, what it's led me to think now, in retrospect, because of recent movements, and the more I've learned about this issue, the more I think it's wrong that kids are not able to know their parents. My feeling, as it has always been, is that every person has a right to know their genetic origins. And ultimately, that's never changed for me. My kids now cannot access that information. Now, if you donate, you have to be willing to be identified or identifiable. Once the child turns 18. Because it's a human right... However, that is not applied to retrospective donations."

Shannon's five children will likely never meet their father.

Zac no longer believes that donor identities should be accessed. "He feels very protective. He feels like the donor has donated and was told that his identity would be protected. Zac now feels it's wrong [to find out the donor's identity]," Shannon says.

"But I also think he has the luxury of knowing, because we found it out anyway, if that makes sense. He knows. He's got a name. He knows stuff about him. There are so many kids out there who are in Zac's position and have no option to know that stuff."

The mum-of-five is fine with donors being able to veto being contacted, but she thinks there should be a "central list" where important information about the donor gets updated, like medical information for example. "My kids have a right to that information too. We don't have a right to impact on his life, if he doesn't choose to have that. I fully support that. Surely, somewhere in the middle, a donor can say, 'I don't want contact, but my medical details are on file'."

The reason Shannon is speaking out publicly is because she knows so many people's lives depend on the fertility clinics getting it right.

"Same-sex parents and people who need sperm donors are not going anywhere. The fertility issue is a multibillion dollar industry. It's so much more expensive now than it ever used to be when I first started. The demand is so much higher than it ever used to be," she says.

"I just think it's time. The issues need to be dealt with."

Helen Edel agrees. Helen and her twin sister Anne Smee were born in the 1960s and only learned that they were donor-conceived when they were 21 years old.

Their mother was told that a university student of the doctor treating her provided the sperm but it took the twins 20 years to find the shocking truth: that their biological father was actually the doctor himself.

Helen and Anne as babies. Image: SBS.

"For 20 years, we didn't know who our biological father was. So you were always looking in the mirror. You're thinking, oh, where's that face come from? Gee, I've got dark eyes and olive skin. Gee, we don't look a lot like the relatives," Helen tells Mamamia.

The doctor even sent the twins a letter about the university student, their supposed biological father - only for them to realise the doctor was writing about himself.

"He wasn't being honest at all. Because my sister rang up when we were 20 to say, 'Oh, who was our donor?' Because we got that letter, but he said, 'Oh, don't be ridiculous. You're here and your father that brings you up...' He tried to pooh-pooh us and my sister had a big fight with that Dr. Doherty on the phone. But he's dead now, died years ago. He was a doctor in Tamworth," she says.

"We joined up with this artificial insemination support group and the leader of it said, 'Hold on, this doctor's writing about himself.' And he was. We contacted his son and he agreed to a DNA test. And it came back with 100 per cent accuracy that we were sisters and brothers.

"And then he came to visit us in Sydney, and boy, we look the same. We looked a lot like Dr Doherty, my sister and I. We've got the Doherty side of the family genetics. We were really excited [to meet our half-brother]. It was great. Because to think there was other blood like you..."

In 2009, Helen and Anne detailed their experience in ABC's Four Corners program Secrets of the Fathers.

"When the show came on years ago, [their brother] had nothing to do with us. He was friendly; we were lucky we got that DNA test out of him. But when that was finished, and that show appeared on TV, that family blacklisted us," she says. "They wanted nothing more to do with us. Because we made it public on that TV show."

Helen and Anne as teens. Image: SBS.

While the twins were shocked when they learned they were donor-conceived, Helen admits there were hints over the years that their dad wasn't their biological dad.

"We never had a strong father-daughter connection because we weren't his sperm. I think he had hang-ups because back in 1959, they didn't counsel men who agreed for their wives to be inseminated. So he had many issues. To tell the truth, Dad didn't really care about us that much. We weren't his own. That's the feeling you get," Helen says.

"But anyway. When we found out, we were shellshocked and couldn't believe we'd been living a lie. Why didn't they tell us sooner? Why was it a dirty secret? Why was it something to be ashamed of? And then how could you talk to your father after that happened?

"Really, the whole family needed to get counselling over that. But back in those days, in the 50s and 60s, people kept hidden secrets."

Like Sarah and Shannon, Helen wants accountability - except she would have liked it from the doctor who was her biological father.

"You think men would be more accountable for their sperm. Doing that and not caring about what happens. You're bringing children into the world. Babies are complex emotional creatures with medical history," she says.

"There should be some sort of law. You can't just do random jacking off to produce a baby and not be accountable to that baby. I don't think it's fair on the kid."

That's the thing - the kid one day grows into an adult. And that adult will come looking for answers. It's this short-sightedness by some fertility clinics that has led these women - Sarah, in particular - on a quest to implement change in Australian law.

These are just three stories from women directly impacted by donor-conception. There are many, many, many more out there.

"I'm happy. I feel a hell of a lot better. I've got answers - some answers at least - about my biological family. And that has done a great deal for me," Sarah says.

"But I only have those answers because I'm lucky. And this should't be a matter of luck. I wouldn't wish on anyone the hole that I found myself in...

"I don't want anyone else to have to go through what I did."

If you have any questions, go to donorconceivedaustralia.com.au/contact-us.

Australia Uncovered – Inconceivable: The Secret Business of Breeding Humans – airs tonight (Tuesday November 1) at 8:30pm on SBS and SBS On Demand.

Feature Image: SBS/Mamamia.

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