Getting pregnant may be more difficult than you think. Even if there’s no placebo, there’s still confirmation and disconfirmation bias and argument from authority i.e. doctors. Perhaps it wasn’t marketed as a perfectly reliable contraceptive and therefore noticing that it doesn’t work would have been more difficult. Medical authorities could explain the failures away with the phases of the moon or the will of the gods or something similarly silly.
Getting pregnant may be more difficult than you think. Even if there’s no placebo, there’s still confirmation and disconfirmation bias and argument from authority i.e. doctors. Perhaps it wasn’t marketed as a perfectly reliable contraceptive and therefore noticing that it doesn’t work would have been more difficult. Medical authorities could explain the failures away with the phases of the moon or the will of the gods or something similarly silly.