成人快手

Sperm counts worldwide have been in steady decline for decades, and a group of tech start-ups are finally giving the problem attention.

Manuela Saragosa speaks to the heads of two such companies: Tom Smith of Dadi Inc, which provides home kits for freezing sperm, and Mohamed Taha of Mojo Diagnostics, which is using artificial intelligence to make male fertility testing more reliable. Plus Mylene Yao of Univfy Inc, which focuses on female fertility, says she has noticed a generational shift in her clients' attitudes, with much more focus now on the joint responsibility of men in achieving a pregnancy.

But why is there such a crisis in male fertility in the first place, and what can men do to improve their chances of having a child? Manuela asks Professor Richard Sharpe of the Centre for Reproductive Health at Edinburgh University.

(Picture: Human sperm and egg cell; Credit: koya79/Getty Images)