Contraceptives have been used by people for tens of thousands of years,
and a few animals have been using their own forms of birth control for
even longer. Spider monkeys eat specific plants which alter their
hormone levels, giving them control over their own fertility. Alpine
marmot mothers will wrestle with their newly-pregnant daughters to force
an abortion if winter is approaching, since a pregnancy will not only
fail in such conditions, but the pregnant marmot usually dies also.
Although most modern human contraceptives are less extreme, there are
those of the past which were nothing less than poison. Antimony is a
toxic metalloid which causes inflammation and disruption of the heart,
seizures, massive organ failure, and death. However, in small enough
doses, it only causes headaches, depression, vomiting, and vertigo. In
medieval Europe, people would purposefully ingest Antimony in small
amounts. The dosage would cause enough trauma to the body to act as a
contraceptive pill without doing any other harm except vomiting,
headaches, and sometimes minor seizures. People also used it to induce
vomiting so that they could eat large meals, or to cleanse their bowels.
Antimony pills would pass through the entire gastrointestinal tract
intact, and would be cleaned and used over and over again. A single pill
would often be used by an entire family for generations.
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