"The physics of sperm vs. the physics of sperm whales" by Aatish Bhatia
Good thing human sperm aren’t normally swimming in water ;-)
Most of the time sperm encounter infertile vaginal secretions and die very quickly (minutes to hours). On the other hand, when a woman is fertile (which is just a few days each cycle), they encounter fertile cervical fluid (…think really slippery like raw egg white) and can live for a long time (DAYS!)… the cervical fluid offers them lots and lots benefits… moving more easily is one of them!
Did you know???
Sperm NEED fertile cervical fluid (or to be "washed" by faux-cervical fluid in the lab) to fertilize an egg!!!
