On the real . . . I believe the answer is yes and no. NO, DON'T try to use it as birth control!

But having known women who absorb it through their skin while working in the 'industry' (trimming on legal farms out west), it can affect ovulation.
I have never known someone to be infertile because of cannabis (and if it was that much of a problem, they could just reverse the effects by not injesting), BUT I have known COUPLES where both people are heavy users and they don't conceive. So I personally believe that both people in a couple have to be using MJ for it to have any type of real BC effect.
Also, I will say combustion/incineration is not going to have any type of positive effect on anyone's fertility. So if you are interested in damage control: vaporize or tincture, don't smoke!
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