Male infertility is having a moment . A Gen Z–founded Silicon Valley start-up, The New York Times recently reported , wants to monetize “sperm racing”; the internet is full of advice on “spermmaxxing” ; and last month Health and Human Services Secretary RFK Jr. called the male fertility decline an “existential crisis,” claiming that in the 1970s, men had “twice the sperm count our teenage boys do today.” Last year he also asserted that “a teenager today has less testosterone than a 68-year-old