The world’s population increases by 1.5m each week and babies born in the UK will use more greenhouse gases during their lifetime than those born in the developing world.
Two doctors, writing in the British Medical Journal, suggest that doctors should talk to their patients about climate change and encourage them to think about the consequences of having a big family.
Investing in contraception would help in the fight against climate change, they argue.
John Guillebaud, emeritus professor of family planning and reproductive health, at University College London and GP Dr Pip Hayes, from Exeter wrote: “Unplanned pregnancy, especially in teenagers, is a problem for the planet, as well as the individual concerned.
“But what about planned pregnancies? Should we now explain to UK couples who plan a family that stopping at two children, or at least having one less child than first intended, is the simplest and biggest contribution anyone can make to leaving a habitable planet for our grandchildren?
“We must not put pressure on people, but by providing information on the population and the environment, and appropriate contraception for everyone (and by their own example), doctors should help to bring family size into the arena of environmental ethics, analogous to avoiding patio heaters and high carbon cars.”