{"id":2084,"date":"2026-10-21T10:51:51","date_gmt":"2026-10-21T10:51:51","guid":{"rendered":"https:\/\/redzine.co.uk\/index.php\/2026\/10\/21\/hot-days-linked-to-fewer-births-two-new-studies-find\/"},"modified":"2026-10-21T10:51:51","modified_gmt":"2026-10-21T10:51:51","slug":"hot-days-linked-to-fewer-births-two-new-studies-find","status":"publish","type":"post","link":"https:\/\/redzine.co.uk\/index.php\/2026\/10\/21\/hot-days-linked-to-fewer-births-two-new-studies-find\/","title":{"rendered":"Hot days linked to fewer births, two new studies find"},"content":{"rendered":"
<\/span> davide bonaldo\/Shutterstock.com<\/a><\/span><\/figcaption><\/figure>\n

Hot weather is associated with fewer babies being born in France<\/a> and Italy<\/a>, according to two new studies. Each day with an average temperature of 25\u00b0C or above was linked to about 360 fewer births in France and about 192 fewer in Italy.<\/p>\n

The drop shows up nine to ten months after exposure to the hot weather. That timing points to fewer conceptions during warm months.<\/p>\n

Hot weather can harm reproductive health in both men and women<\/a>, which could mean fewer pregnancies. It may also change people\u2019s sexual behaviour, and both explanations are possible.<\/p>\n

France and Italy are not the first places where researchers have spotted this. Similar studies in the US<\/a>, South Korea<\/a>, Spain<\/a> and across Europe<\/a> have also found a link between hot weather and fewer births. As the evidence builds, it looks less like the quirk of a couple of countries.<\/p>\n

Earlier studies in the US<\/a> and Hungary<\/a> found that some of the missing births were \u201ccaught up\u201d in the months after the dip, as if couples had simply put off having a baby. But the French and Italian studies see no sign of this, so some births in these two countries may be lost for good instead of moving to another time of year.<\/p>\n

A warming climate meets an ageing Europe<\/h2>\n

Italy and France already have falling birth rates, so each lost birth is consequential. Italy was among the first to drop below 1.30 children per woman<\/a>, back in the early 1990s. Demographers call this \u201clowest-low fertility\u201d, and it makes a population grow older rapidly.<\/p>\n

France held on to higher fertility than many of its neighbours for longer. But births there fell by 22% between 2010 and 2025, according to researchers at the National Institute of Statistics and Economic Studies<\/a>, and are now well below the level needed to keep the population stable.<\/p>\n

Meanwhile, Europe is the fastest-warming continent<\/a>. Climate scientists say parts of it have become \u201cregional heat wave hotspots\u201d<\/a>, with hot weather arriving faster than climate models predicted. <\/p>\n

The Mediterranean is especially exposed, and in Italy<\/a> average annual temperatures have risen by almost 2\u00b0C over the past 60 years \u2013 a warming rate higher than the global average. <\/p>\n

Europe had several long, severe heatwaves this summer, and M\u00e9t\u00e9o-France said France\u2019s was its warmest since measurements began<\/a> in 1900.<\/p>\n

If heat does reduce births, the effect would hit hardest in countries where fertility is already low and populations are ageing fast. That gives climate change a place in family and population policy.<\/p>\n

\n \"Pensioners
\n Many European countries face ageing populations.<\/span>
\n Real life photo\/Shutterstock.com<\/a><\/span>
\n <\/figcaption><\/figure>\n

What we know \u2013 and what we don\u2019t<\/h2>\n

Still, there are limits to what these studies can tell us about the effects of heat on birth rates.<\/p>\n

Both studies account for normal yearly patterns in births and temperatures, at regional and national level. But because they look at whole populations over time, they cannot show as clearly whether heat itself causes fewer births as studies that compare people under carefully controlled conditions.<\/p>\n

The studies also rely on data from past decades. With the weather changing fast, the link between heat and births may already look different today, and it could shift again in the future.<\/p>\n

Both the new studies estimate that the link is real but fairly small. Changes in family norms and money worries are still the main explanations for falling fertility in Europe. But if hot weather becomes more frequent and more intense, climate change could play a bigger part in the years ahead.<\/p>\n

\"The<\/p>\n

Raya Muttarak receives funding from: 1) the FER-MO project funded by the European Union\u2019s Next Generation EU, Missione 4 Componente 1 CUP J53D23009530001; and 2) European Research Council (ERC) under the European Union\u2019s Horizon 2020 research and innovation programme (grant agreement No 101002973, POPCLIMA). Views and opinions expressed are, however, those of the authors only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible for them. She is also affiliated with the Department of Statistical Sciences, University of Bologna.<\/span><\/em><\/p>\n

Federica Querin was supported by the European Research Council (ERC) under the European Union\u2019s
\nHorizon 2020 research and innovation programme (grant agreement No 865356, GENPOP). Views and
\nopinions expressed are, however, those of the authors only and do not necessarily reflect those
\nof the European Union or the European Research Council. Neither the European Union nor the granting authority can be held
\nresponsible for them<\/span><\/em><\/p>\n

Sophia Noel was supported by the European Research Council through the European Union\u2019s Horizon 2020 research and innovation programme under the Grant Agreement No. 101117173 (WIDOW). Views and opinions expressed are, however, those of the author only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible for them. She is also affiliated with the Department of Digital and Computational Demography at the Max Planck Institute for Demographic Research
\n<\/span><\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

davide bonaldo\/Shutterstock.com Hot weather is associated with fewer babies being born in France and Italy, according to two new studies. Each day with an average temperature of 25\u00b0C or above was linked to about 360 fewer births in France and about 192 fewer in Italy. The drop shows up nine to ten months after exposure […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-2084","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/posts\/2084","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/comments?post=2084"}],"version-history":[{"count":0,"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/posts\/2084\/revisions"}],"wp:attachment":[{"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/media?parent=2084"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/categories?post=2084"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/tags?post=2084"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}