Serious studies have measured the concentration of corticosteroids, the so-called stress hormone, in the saliva of women underdoing fertility treatments that suggest that stress directly affects the probability of pregnancy.
However, I must remember that the treatment, and even more, the so-called Two Week Wait period is really stressful for each and every woman, so the possible effect of stress on the success of the treatment has already been disclaimed.
In brief, it does affect stress in treatment, but this effect has already been calculated by the doctor when in consultation, you talked about the probability of treatment success.
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