What Chrissy Teigen and John Legend did would be illegal in Australia.

TV host and model Chrissy Teigen is pregnant.

She and her husband – multiple-Grammy award-winning artist John Legend – are expecting a little girl.

They’re expecting a little girl who is a little girl by design, not chance.

Teigen and Legend chose the gender of their unborn child through a process called Preimplantation Genetic Screening (PGS). PGS is a perfectly legal – albeit controversial – option that is offered by some fertility clinics in the United States to patients already accessing IVF.

Teigen told People magazine this week, “I’ve made this decision… Not only am I having a girl but I picked the girl from her little embryo. I picked her and was like, ‘Let’s put in the girl.'”

“I think I was most excited and allured by the fact that John would be the best father to a little girl. That excited me,” Teigen said, when pressed on the question of why she wanted a girl.

Teigen took to Instagram in October to announce her pregnancy.

John and I are so happy to announce that we are pregnant :) As many of you know, we’ve been trying to have a baby for a while now. It hasn’t been easy, but we kept trying because we can’t wait to bring our first child into the world and grow our family. We’re so excited that it’s finally happening. Thank you for all your love and well wishes. I look forward to all the belly touching! Xx

A photo posted by chrissy teigen (@chrissyteigen) on Oct 12, 2015 at 4:55pm PDT

Here in Australia, the procedure is illegal in several states, including NSW and Victoria. In the remaining states and territories there is no governing legislation but there are also no fertility clinics offering the procedure. China, the United Kingdom and Canada have also outlawed gender selection.

To call the issue fraught, is an understatement.

Since her interview with People, Chrissy Teigen has been accused of playing God, of being selfish and ungrateful, of not deserving to have children and a whole raft of other labels too cruel to repeat. While gender selection is not uncommon in the United States, speaking openly about it is. And Teigen’s candid comments, coupled with her public profile, has refuelled the ethics debate around the issue.

So, where do you stand?

With more and more Australians heading overseas to access the procedure, it’s not simply an issue of outlawing gender selection here at home. The reality is that Australian parents are having babies, who will ultimately be Australian citizens, whose gender has been predetermined. How do we, as a population, feel about that?

There are a whole raft of arguments against gender selection.

First and foremost is that natural selection is an important part of evolution, so any intervention should be treated with extreme caution. Nature has always had its own ways of ensuring that the balance of male and female remains roughly equal; a fact that has been critical to the continuation of the human race. Is that really something we want to mess with?

Having said that, IVF itself is, by definition, a form of intervention with natural selection. However IVF is an intervention that the majority of us are comfortable with. If science can allow couples or individuals who would otherwise be unable to have children to do so, then what’s wrong with that? In my book, it’s pretty damn wonderful.

So what’s wrong with taking that one extra step and allowing parents to choose which embryo is implanted based on gender, as well as medical viability?  Well, a few things. A few extremely complex, ethically confusing things.

If we allow parents-to-be to choose the gender of their child, what else are we willing to let them choose? Ethicists caution against gender selection by warning it’s the first step towards designer babies. We already make medical decisions about the future of foetuses based on some genetic disorders and abnormalities. But imagine if parents could choose the eye or hair colour of their future child. Or determine factors like their baby’s metabolism or athleticism. Their beauty. Their IQ…

Also, we have to consider why it is that parents would want one gender over the other. Parents generally have a preference for a boy or a girl based on entrenched gender stereotypes. Stereotypes that tend to be harmful, particularly for boys and girls who don’t exhibit traditionally ‘masculine’ or ‘feminine’ character traits. Arguably, there has never been a more gender equal time in our history and that is a marvellous thing. But allowing parents to choose the gender of their baby would surely inhibit – rather than further – this progress.

Then there’s the issue of setting one gender above another. In India and China there is a strong cultural preference for boy children over girls. That preference, coupled in particular with China’s One Child policy, has led to significant numbers of abortions for gender selective purposes and caused a skewing of male-to-female ratios.

So to answer the question of “Why intervene with nature to allow people to become parents but not allow them to choose the gender of their offspring?” I would say this: Just because we can do it, doesn’t mean we should.

Watch: Sunday Night – A Miracle Baby. Post continues after video…

Law-making requires us to draw – sometimes seemingly arbitrary – lines. For example, Australia has decided that young people shouldn’t be able to drive until age 16 or drink alcohol until age 18. We’ve decided that terminating a pregnancy is permissible but only until the foetus reaches a certain number of weeks. We’ve decided that science should be used to help people who cannot otherwise have children, to do so. Those lines have moved over time, in line with our society’s changing values and no doubt, they will move again in the future.

And to my mind, allowing parents-to-be to choose the gender of their child falls on the wrong side of the line.

Babies aren’t products. They’re people.

We’re not deciding, which brand of pram to buy – we’re creating a human being with thoughts and feelings and strengths and weaknesses. The glorious lottery of life means we don’t know what we’re going get and yet we commit to falling in love with that little person regardless. For me, that’s the mot beautiful thing about becoming a parent. Whether that child comes into your life through love-making, IVF or adoption – the love they receive from their parent(s) is always going to be unconditional.

Unconditional love.

That is nature’s design. And it’s got nothing to do with chance.