Hòn lửa vĩ đại

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Women have a variety of methods for contraception (tránh thai), but only two methods are commonly available to men: condoms (bao cao su) and vasectomies (cắt ống dẫn tinh). Both methods have their drawbacks (mặt hạn chế).

Condoms can break, and some men are allergic (dị ứng) to the latex in standard condoms. Vasectomies are surgical procedures that can be painful (đau đớn) and difficult to reverse (khó đảo ngược).

So the search for alternative male contraceptive options continues, and one method currently being investigated is nanocontraception.

Nanocontraception is based on the idea that nanoparticles—here, about 100 nanometres in diameter, or roughly one-thousandth the width of a piece of paper or of a strand of human hair—can somehow be delivered to the testicles (tinh hoàn), where they can be warmed.

If you could warm up the testicles just a bit, you would have a way to turn sperm production on and off at will because the warmer they get, the less fertile they become. But it's a delicate process because the testicles can be irreversibly destroyed if they become too warm; the tissue dies and can no longer produce sperm, even when the testicles return to their normal temperature.

Bài trước: Bảo sao chúng vui thế