Russia’s fight against the West and its values has taken aim this week at an “ideology” that the Kremlin and its allies say threatens the country’s very foundations: people not wanting to have children.

Lawmakers have proposed a ban on “propaganda of conscious refusal to bear children,” Vyacheslav Volodin, the speaker of the lower house of parliament and an ally of President Vladimir Putin, said in a post on Telegram on Tuesday.

It is the latest effort by authorities to combat the…