Mr. Nunn is an author and journalist in New South Wales, Australia.

In 2019, after thorough deliberation, I made the most meaningful decision of my adult life to become a dad. And, while joyously successful -- I now have three sons and two daughters -- I've never met them. That's because I donated sperm to a fertility clinic in New South Wales, Australia, where I live. At this stage, a better word for me is "donor."

Yet I've left open the opportunity of meeting my seven children (I'm eagerly awaiting news from two further pregnancies) once they reach adulthood. Anonymous donation isn't allowed in Australian clinics, meaning my biological children can request contact with me after they turn 18. I sincerely hope they do if it feels right to them.

But I wouldn't donate sperm in the United States. Anonymous donation, legal in most states, denies people conceived with sperm donations their right to know where they came from, and to an eventual relationship with their genetic dads. More broadly, the absence of legally enforced caps on the number of pregnancies a donation can lead to makes accidental incest an alarming possibility and forces people conceived via donors to grapple with the discovery that they are part of a potentially sprawling family in which they may struggle to form meaningful connections. Until the American fertility industry is more aggressively regulated, these practices can hurt all involved -- most especially the children.

The consequences stretch beyond the borders of the United States, which by some estimates is one of the world's largest sperm exporters. Many donor-conceived people born abroad originated from an American sperm bank.

The country continues to drag its feet on national reform. The Food and Drug Administration rejected a 2018 petition to require donors to provide post-conception medical updates so that their children could be screened for hereditary diseases. Congress hasn't acted on assisted reproduction since 1992.

Australia is one of at least 15 countries in which people conceived via donors can identify their donors from at least age 18 (earlier in some places). In New South Wales, they can also track their half siblings through a central register. New South Wales also imposes a strict limit of five recipient families per donor -- a number that feels manageable for people tracking down their half siblings, for the donors tracking down their genetic children and for the recipient parents looking after the well-being of their curious children.

The United States should look to countries like Australia to inspire better regulation. It should also wise up to the fact that anonymous donation is no longer the reality it once was, thanks to DNA testing services like 23andMe. Our genetic and hereditary origins are more easily accessible than ever before. A system that encourages keeping secrets and lying ought to be legislated out of society.

The country's fertility industry is stuck in the past in other ways, too. As a gay man who has had sex with another man within the last five years, I'm banned from donating sperm to American clinics (although moves are afoot to change this). Being gay was, in fact, a big reason I donated here in Australia -- it won't be easy for me to have my own children, and this felt like a way of helping families struggling with infertility, and potentially having a future relationship with my donor-conceived children if and when it felt right to them and their families.

Even as a donor whose identity is partly obscured, my recipient families know a lot about me -- from my educational achievements and sexual orientation, to how often I exercise. Crucially, they know my full medical history, since early screening could help prevent genetic diseases and give doctors information on underlying conditions. They have a photo of me taken when I was 8 years old, giving the families some sense of what I look like while I remain officially unidentifiable. They don't know my address.

In return, all I know about the children conceived with my sperm donation is that they live in the same Australian state, that they were inevitably very much wanted by their parents, and -- as is my powerful hope -- they will be very much loved.

I wish donors and recipient families in America could expect the same. A handful of American states, including Washington, California, Rhode Island and Connecticut, have enacted laws that permit children to request contact with their donor dads after they turn 18. All of them also give those same donors opt-out clauses, allowing them to remain forever anonymous to the humans they created.

In my view, it's unethical. While clauses exist for people conceived via donors to learn their medical history in those same states, that's, frankly, the very least they're entitled to.

U.S. laws ignore the psychological and emotional needs of children born through sperm donation. Before donating, I learned that many crave early contact with their donors to understand their identity, genetically inherited character traits and the personal connection of bloodline. Such relationships can form a crucial part of their sense of self and emotional well-being.

That's why I've made clear in my file that I welcome contact even before age 18. Australian clinics help facilitate this, though they do caution that courts may mandate child support payments for any children if donors begin meeting regularly.

There's evidence that change is possible in the United States. Next month, groundbreaking legislation goes into effect in Colorado, making it the first American state to ban anonymous donation and require donors to agree beforehand that any children can request identifying information. It also will limit each donor to no more than 25 families.

It's a start. But 25 is still too high. If each of those families has just two children, that's still 50 children. I don't want this for my children. Besides imposing a lower cap on the number of families, the individual states should begin operating mandatory, government-run donor-sibling registries so that these people can connect and form authentic relationships with their half siblings, should they wish.

Children deserve transparency about their genetic origins and families. During the donation process -- which included two psychology sessions -- I was invited to write a letter to my future children. In it, I promised I'd always be there for them.

Even if I never meet them, while I'll feel slightly disappointed, it honestly enriches me to know they're here. It feels as if my life has meant something.

Gary Nunn (@garynunn1) is an author and journalist.

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