The reason for Italy’s ‘demographic winter’

Lara Bussi Trabucco, whose arrival was the first birth in her village of Pagliara dei Marsi, Abruzzo, Italy, in almost 30 years. Photograph: Roberto Salomone/The Guardian

The Italian “demographic winter” has a number of causes, but rising male biological infertility is not one (A child is born: Italians celebrate village’s first baby in 30 years, 26 December).

A lot of worry about falling sperm counts has been generated by some studies, but a more recent meta‑analysis found, through inclusion of regional controls, an increase in US sperm counts between 1970 and 2018. Sperm counts may be falling in places like the Chinese province of Henan, which has substantial air and water pollution, but there is limited evidence that sperm counts are falling in the developed world.