Hayley, who proposed to Fiona in April 2019 after just eight months of dating, explained the pair both want to carry a child at some stage.
"Fi is going first because she is older. I really want to carry a bub too but Fi will go first just because of the body clock on fertility, so her going first is best," Hayley told the publication.
"I will give it a crack after we have our first child," the sports reporter added.
Fiona added that the couple want to "have the babies quite close to each other", joking that they will "lose all the sleep at once".
Fiona has previously spoken about her fertility battles to her 94,000 Instagram followers.
In May, she revealed she was really struggling with the process.
"Fertility can be a scary word we don't really like to talk about. Every day is hard, I have never questioned myself and my body so much," she wrote on Instagram.
"Trying to do all the things to make myself the perfect home for a little human, but sometimes even that is not enough.
"It's a struggle mentally and physically and I just want to say to anyone else out there on this journey you are not alone!"
Fiona and Hayley have been together for about two years. They first met after Hayley messaged Fiona on Instagram, with the pair later meeting up in real life for a drink.
Fiona "came out" publicly for the first time in 2017, when she revealed she was dating personal trainer Lara Creber.
Lara was Fiona's first same-sex relationship. The pair split around April 2018 after dating for a few months.
At the time, Fiona said she was very "happy" with Lara and not focusing too much on the chatter on social media about her sexuality.
"This is the first female relationship I've had and I didn't think there would be interest in it because it's just normal life," she told The Daily Telegraph.
"I'm at a place in my life where I'm just focusing on what makes me happy and not caring what other people think and focusing inwardly."
She said she was surprised her sexuality had become such a hot talking point.
"I was just a bit disappointed that it is such big news, that there are photos of me kissing a girl," she said.
"There's nothing 'scandalous' about it. Lara and I met on a trip to South America and I'm all about falling in a love with a person and yes, I've fallen in love with Lara."
This story originally appeared on our sister site, Now To Love.