baby boom
noun [ C usually singular ] uk/ˈbeɪ.bi ˌbuːm/ us/ˈbeɪ.bi ˌbuːm/
生育高峰，婴儿潮
a large increase in the number of babies born among a particular group of people during a particular time
There was a baby boom in the UK and the US after the Second World War. 二战后，英国和美国都出现了一次生育高峰。