yeah. i've heard the rythm (timing) method of birth control isn't terribly effective as a method of birth control. and of course it is worth stuff all with respect to STD's...

it involves figuring out the time when you are meant to be 'least fertile' and sometimes is used in conjunction with the withdrawal method.

but... people still get pregnant.

not sure how long sperm last for...

that was interesting, thanks guys. funny that i never learned about ovulation. i skipped that year at high school so while i did this unit on 'puberty change' i missed out on the later unit on sex ed where they went into more detail with what was going on more generally...