Everyone loves the pitter patter of tiny feet, though there's nothing delicate about the carbon footprint of a brand new baby.
Depending on who you ask, having children is one of the most destructive things that a person can do to the environment.
According to recent research from Lund University in Sweden, having one fewer child can save an average of 58.6 tonnes of CO2-equivalent emissions per year. According to the study's lead author Seth Wynes, "a US family who chooses to have one fewer child would provide the same level of emissions reductions as 684 teenagers who choose to adopt comprehensive recycling for the rest of their lives".
Yet a growing number of women are deciding against having children for a different reason entirely. Chiefly, it's fear at the seemingly inexorable decline of the planet, and how hostile and difficult an environment future generations are likely to live in.
It's a concern that Alexandria Ocasio-Cortez, the youngest woman to serve in the US Congress, voiced recently when she told her three million Instagram followers that "there's scientific consensus that the lives of children are going to be very difficult" as a result of climate change. "It does lead young people to have a legitimate question: Is it OK to still have children?"
That we are heading towards ecological catastrophe should come as a surprise to nobody, but a cohort of climate-conscious women and men are taking a stand. Some might see it as extreme, or a case of making the personal political, but there's little denying that BirthStrike is getting people's attention.
Founded by British musician and activist Blythe Pepino, BirthStrike is a voluntary organisation for women and men, around 300 in number so far, who have decided against starting a family in direct response to the world's myriad ecological crises.
Their aim is not to discourage others from having children, or to shame those who have, but to shed visibility and disseminate information on the severity of the current threats to our environment. Population control is only one spoke in a very large wheel, and the entire system, note BirthStrikers, needs a drastic overhaul.
The response to the advent of the BirthStrike movement has been varied. It has been met in some quarters by plain old-fashioned misogyny. Some laud the activists for effectively putting their money where their mouths are. Others have noted that their action is an extreme one, and that rumours of the earth's apocalyptic demise have been greatly exaggerated. Many BirthStrikers believe that the window of opportunity is closing fast and that future progeny are in for a rough ride.
BirthStrike is a support group for women and men of a similar mindset as much as it is a political protest.
In a recent interview, Pepino admitted that she had once hoped that children would be part of her life, but the mounting evidence about the reality of the changing environment meant that she couldn't "really bring herself" to have children. Still, she remains hopeful that she will get the chance to eventually change her mind.
Even before the inception of the BirthStrike movement, Castleknock-born post-doctoral researcher Laura Kehoe had made a similar decision to not start a family years ago. If anything, hearing about BirthStrike has made Laura, a wildlife biologist who has worked in sustainability research for the last decade, feel less alone in her own personal decision.
"I still remember the day I heard about climate change in geography class at 16," she says. "I remember thinking: 'Why isn't everyone freaking out about this? This is just terrifying.' It wasn't just climate change - there was also biodiversity loss, water scarcity, food distribution, crop decline; the fact that we only have 60 years of topsoil left. Together, it's working to create this terrible storm. I have a nephew and I am scared for his future.
"I don't think it's about trying to make a stand," she adds. "How I understand the movement is that we are terrified for the most likely future for humanity in the next few decades, and we don't feel it's fair, on a personal level, to bring a child into the world."
Did Laura ever have plans to have children to begin with?
"It's a tricky thing," she notes. "I learnt about this when I was 16, so it's hard to pick apart what I wanted. The issue is that once you really learn about this stuff and let it sink in, it's tough psychologically. But it's tougher still when no one gets it.
"Often, the response [to her decision to not have children] is an uncomfortable one. One common response is, 'oh, but you're exactly the type of person that should be having kids as we need more conscientious people and you could raise your kids to be really conscientious'. But if I had kids, they would probably rebel and go buy a Hummer," she jokes.
Laura's partner is supportive of her decision not to start a family, and feels the same way.
"But when your social group doesn't get it and they don't think about it the way you do, they think you are fixating on it and have some sort of psychological issue. Then you try to say to them, 'this is science! Scientists are literally saying this'. It's futile to try to change people's minds, but it is a good way to show how serious the situation is. It's great to see more people waking up to it."
The question does beg to be answered, however: is deciding not to have children for these reasons something Laura might regret in the future? After all, many people want to have children for reasons independent of climate.
"It's a question that's also asked of my mother," notes Kehoe. "Of course, it's possible. Right now, I think we have around a five per cent chance of avoiding collapse. The chance that I would regret having a child under such crazy societal unrest is higher than the chance that I would not regret having a child.
"Maybe we'll see society turning around and I'll be in my 40s by then, but it's looking less and less likely," she adds. "I can only make a decision like that in the present time, and according to the best available knowledge."
As to what Laura and other Birthstrikers would like to see happen in the future, she says: "We need a shift in consciousness. We need to fully understand how much we rely on the earth. We are not the engineers of nature who can dominate and extract from the earth at will. We are part of the system, and we need to learn pretty fast that every piece of it relies on the other. When we make decisions, we tend to make short-term decisions for short-term profits for various corporations.
"I'd love to see a Citizen's Assembly take back power to the people. We need to rise up as a society and make a stand. After all, we've tried everything else."