Worries over uncertainty about the future, being able to provide, as well as concerns that having children would contribute to overpopulation and overconsumption were given as reasons for not starting a family.
Research published in the journal Plos Climate involving nearly 11,000 people found political sentiment – such as refusal to have children until systemic change was enacted – was also a motivating factor.
“Recent media attention has been paid to a growing number of individuals factoring their concerns about climate change into their childbearing plans," said lead author Hope Dillarstone, a former student at the UCL Institute for Global Health.
“However, we were concerned that public discourse may have oversimplified this relationship.
“Our first-of-its-kind study shows that there is a complex and intricate relationship between climate change and reproductive choices, with differences noted both within and between countries across the world.
“Our analysis shows that not only are many people concerned about their child’s welfare growing up in a world of uncertainty, but they are also considering the impact of having children on the environment, their family’s ability to subsist and their politics.”
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In a first systematic review exploring the effects of climate change-related concerns on the decision to have children, the researchers looked at 13 studies involving 10,788 people from countries such as the US, Canada, New Zealand and various European nations including the UK.
They found the concerns were associated with a desire or intent for fewer or no children.
Conversely, in countries such as Zambia, people reported being in favour of having more children because they were concerned about their ability to support their family without the household labour provided by additional offspring.
Ms Dillarstone added: “Understanding why some people choose to adjust their reproductive decisions as a result of climate change may prove instrumental for shaping public policy, showing a need for collaboration among policymakers to incorporate local-level environmental concerns within national and international climate change, mental health and sexual and reproductive health policies."