London (CNN) Climate change is rapidly changing the environment we live in. But how far would you be willing to go to help save the planet?

Would you skip school? Eat pig's feet ? Deliberately get arrested ? How about forgo having kids?

For 33-year-old British musician Blythe Pepino the latter is a reality. Her fears about climate change are so strong she has decided not to have biological children.

"I really want a kid," she told CNN. "I love my partner and I want a family with him but I don't feel like this is a time that you can do that."

Pepino believes that there will be an "ecological Armageddon" and founded BirthStrike at the end of 2018. BirthStrike is a group of people who are declaring their decision not to have kids because of "the severity of the ecological crisis."

So far, over 330 people have joined, of which Pepino estimates 80% are women.

'Inheriting a world worse than ours'

The BirthStrikers have decided they can't bring children into a world facing an ecological breakdown, and where scientists predict climate change will bring bigger wildfires , more droughts , and food shortages for millions of people.

In 2018, the UN International Panel on Climate Change (IPCC) warned the planet only has 11 years to prevent catastrophic climate change.

"You are gambling with someone else's life," said Cody Harrison, a 29-year-old who recently joined the group. "If things don't go well, that human is not going to have a very good life."

"When climate change gets worse, it multiplies other things. It's like dominoes that are falling," said Lori Day, another member of BirthStrike. "It goes beyond sea level rise and storms. It affects food production, migration, resources and war."

BirthStrike is one of a number of groups around the world that are questioning the ethics of having children in a warming world. Conceivable Future , a network of women in America, was founded in 2015 to bring awareness to "the threat climate change poses to reproductive justice," although that group's members haven't discounted having children.

"The data says there's a ticking clock," said Josephine Ferorelli, a co-founder of the group. "The 11-year window more or less approximates a lot of our reproductive windows as well.

"What kind of harm will a hotter and more painful world inflict on my child? Nobody has the answers for that," she said.

U.S. Rep. Alexandria Ocasio-Cortez at a news conference unveiling the Green New Deal resolution, February 7, 2019.

In March, US congresswoman Alexandria Ocasio-Cortez told her 3 million Instagram followers, "there's a scientific consensus that the lives of children are going to be very difficult... is it still ok to have children?"

More children, more emissions

In addition to fears surrounding the quality of life for future generations, some BirthStrikers don't want to have children because of the extra emissions that their kids, and their descendants, will produce.

Population Matters , a UK-based charity that boasts David Attenborough as a patron and aims to achieve a "sustainable human population," argues that as the population increases, so will carbon emissions and loss of tropical forests, as well as other environmental impacts.

By 2030, the UN estimates there will be around 8.5 billion people on the planet and by 2100, there could be as many as 11 billion.

Currently, the World Bank estimates the average person emits 5 tons of carbon dioxide a year.

Most of the world's projected population growth will be in developing countries, but developed nations have much higher average CO2 emissions. The average American emits 15.6 metric tons per year, while Sri Lanka and Ghana emit less than one ton per capita.

Consumption, not population?

So, should everyone in industrialized countries consider having fewer children, to reduce emissions? It might not be that simple.

A 2014 study concluded that reducing the human population is "not a quick fix for environmental problems." Using models, it found that even a worldwide one-child policy would give a global population of around 7 billion by the end of the century -- much the same as today's population.

The scientists concluded that although reducing population "might benefit our great-great-great-great grandchildren," it is not a short-term "elephant in the room" solution.

Instead, the study suggests society should focus on reducing the carbon footprint we already have and limiting per-capita consumption.

"If everyone consumes the way the US did, we would need another four to six earths," said Meghan Kallman, co-founder of Conceivable Future. "It's not actually about the number of people. It's how those people consume."

"From a carbon perspective, one baby more one baby less, the way that you approach it as an individual has no significant impact whatsoever," said Ferorelli. "It's about why it is so carbon intensive in the West to have a child in the first place."

The opportunity cost of a child

Both BirthStrike and Conceivable Future are quick to say that they do not endorse coercive population control methods or judge anyone for having children.

Nor should the groups be conflated with the anti-natalist movement, the philosophy that it's morally wrong to procreate, because of the suffering that comes with life.

"I try not to judge anybody for their own choices," said Harrison. "Once I'm ready I'd like to adopt."

Day even wondered whether a child that is due to be born could be the child who solves the climate crisis.

"Sometimes I wonder, what if Greta Thunberg's mother had not wanted to have children because of climate change?" said Day, referring to the 16-year-old girl who has inspired youth climate protests worldwide, after staging a sit-in outside the Swedish parliament every Friday.

Creating political action

For the groups, their declarations are less about individual actions and more about a collective effort to prompt political change.

"I did have a sneaky feeling that it was going to rock the boat of certain patriarchal groups," said Pepino. "I wanted it to freak people out and I think that it has."

Pepino said that there had been a "violent backlash" online after an interview she did on Fox News, but says now there is a lot more solidarity.

"Knowing that there are people out there who feel the same way helps us come together and say something really politically powerful," said Kallman. "This is a huge freaking problem and we need to solve it right now."

The groups also hope to channel the energy they would have used to raise children into activism and rebellion.

"I am in a position to be an activist," said Pepino. "It's a stronger calling than motherhood, even though I still mourn the idea."

"Now is the time to create the disruption and bring the system to its knees because it is just ignoring it," she said.

"Every day that we don't act is another day that more people will die, more species will become extinct and more likely we will be heading to a completely uninhabitable planet."