Natural selection: Jayne Cornwill with daughter Emmerson. Credit:David Solm

The technology - known as "pre-implantation genetic diagnosis", or PGD - is illegal in Australia, unless it's used to screen out hereditary disorders. As such, I've faced a backlash from even my closest friends. I've been criticised for "playing God", messing with nature and being superficial. I know that, to a childless woman struggling with infertility, I might seem ungrateful because I already have three healthy sons. But unless you've experienced "gender disappointment", you can't understand how crippling it can be. My desire for a daughter caused me to spiral into depression and left me virtually housebound. Every time I went out, toddlers in pink seemed to taunt me.

I'm not alone in going to such lengths to have a daughter. Dr Daniel Potter, the US fertility specialist who treated us, has helped more than 1000 Australian couples "gender balance" their families. When we visited his clinic, HRC Fertility in Newport Beach, during our 16-day stay, we met 14 other Aussie couples in the waiting room, many of them too frightened to tell their friends or family why they were really visiting California.

Ever since I was little, my only goal in life was to have a daughter, and as an adult that desire only grew stronger. I come from a mixed-gender family with two older brothers and an older sister, and I saw the benefits of growing up with both perspectives. I also think society pushes the idea of the "perfect" family being two parents, with two children - one boy and one girl. I certainly thought so. I'm also close to my mother and always dreamed of having my own little mummy's girl.

When I had my first son, Nathan, seven years ago, I wasn't immediately disappointed because I just assumed - somewhat naively - that our next child would be a girl. But three years later, when I fell pregnant for the second time, I was in for a nasty reality check at the ultrasound. I know that every mother is meant to say, "I don't care what the sex is as long as they're healthy", but I couldn't hide my disappointment from my husband when the nurse said, "It's a boy." I'm sure she assumed my tears were caused by joy.