No side-effects, no movement in the food chain, safe for pregnant creatures

[xoder]

Porcine Zona Pellucida Vaccine:

Why in the heck don't we (as humans) have this option? Yes, it wouldn't work for immunocompromised persons, and 90% is not incredibly excellent. Look at diaphragms, though. Success rates between 83% and 94%. Condoms are between 85% and 98% and withdrawl is between 72% and 96%.

Comments

[zandperl.livejournal.com]

Here's a table form of that info, presented as number of women who get pregnant out of every 100 using that method. A version of it is in every package of The Pill. The first time I read it I was shocked to see that withdrawal actually was so effective.